Patent Application
20240217968
The present invention relates to PARP7 inhibitor compounds, and in particular to PARP7 inhibitor compounds for use in medicine. The inhibitors of the invention may be used in pharmaceutical compositions, and in particular pharmaceutical compositions for treating a cancer, an infectious disease, a central nervous system disease or disorder, a pain condition and other diseases, conditions and disorders. The invention also relates to methods of manufacture of such inhibitors, and methods of treatment using such inhibitors.
Monoclonal antibody-based therapeutics targeting immune checkpoints, most notably the PDL1-PD1 axis, are transforming approaches to the treatment of cancer. These agents have been demonstrated to elicit complete and durable regressions of metastatic disease, most notably in the setting of malignant melanoma. PDL1 expressed by tumour (and other) cells delivers an inhibitory signal via ligation of PD1 on T-cells. Blocking this interaction with antibodies targeting PD1 or PDL1 results in T-cell reactivation, recognition of tumour cell neoantigens and CD8+ve T-cell-mediated tumour cell killing (Hashem O. et al. PD-1 and PD-L1 Checkpoint Signalling Inhibition for Cancer Immunotherapy: Mechanism, Combinations, and Clinical Outcome. Front Pharmacol. 8: 561, (2017)). Despite these developments the fact remains that tumour responses are only observed in a minority of cancer patients. Furthermore, in many patients that do respond responses are not durable. There is an urgent need to identify and develop complementary therapies that will broaden the population for whom immunomodulatory therapy delivers benefit.
Immune checkpoint inhibitors (ICIs) such as anti-PD1 and anti-PDL1 act by relieving checkpoint restraints on anti-tumour T cell responses. They work best against immunogenic, T-cell inflamed or hot tumours. In contrast, ICIs are poorly efficient in cold tumour microenvironments (TMEs) that are largely devoid of T cells and infiltrated by immunosuppressive cells. In hot TMEs, increased expression of type I interferons (IFN-I) and IFN-stimulated genes (ISGs), such as T-cell attracting chemokines, contribute to potent anti-tumour responses. One emerging therapeutic strategy to transform cold tumours into hot exploits the use of pattern recognition receptor (PRR) agonists. Indeed, combinations of ICIs with agonists of RIG-I Helicase, Toll-like receptor 9 (TLR9) or stimulator of interferon genes (STING) have now reached clinical evaluation.
The innate immune system provides a first line of host defence and plays a crucial role in initiating and driving the development of adaptive immune responses. The cytosolic DNA sensor cyclic GMP-AMP synthase (cGAS) can be activated by double stranded DNA arising from the genomes of invading pathogens and also by aberrant cytosolic levels of host DNA that are generated in tumour cells (Chen Q et al. Regulation and function of the cGAS-STING pathway of cytosolic DNA sensing. Nat Immunol. 17: 1142-9, (2016)). Activation of cGAS leads to the generation of cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) which induces dimerization of Stimulator of interferon genes (STING). STING subsequently translocates from the endoplasmic reticulum to the Golgi where it recruits and activates TANK-binding kinase 1 (TBK1). TBK1 phosphorylates interferon regulatory transcription factor 3 (IRF3) which drives the production of type I interferons and supports the generation of immunity (Zhu Y et al. STING: a master regulator in the cancer-immunity cycle. Mol Cancer 18: 152 (2019)). As such, activation of the STING pathway has become of increasing interest to the cancer drug discovery community as a potential strategy to boost the development of adaptive immune responses to tumour cell neoantigens (Sivick K. E. et al. Magnitude of Therapeutic STING Activation Determines CD8+ T Cell-Mediated Anti-tumor Immunity. Cell Reports. 25: 3074, (2018)). Cytoplasmic DNA sensing has also been linked to inactivation of cellular proliferation providing an additional potential mechanistic axis that may contribute to control of tumorigenesis (Paludan S. R. et al. DNA-stimulated cell death: implications for host defence, inflammatory diseases and cancer. Nat Rev Immunol. 19: 141-153, (2019)).
Cancer cells can exhibit a chronic Interferon-stimulate gene (ISG) signature triggered by a STING-dependent pathway, which results in a unique primed cancer cell state that is sensitized to respond to aberrant nucleic acid accumulation (Liu H et al. Tumor-derived IFN triggers chronic pathway agonism and sensitivity to ADAR loss. Nat Medicine. 25: 95-102, 2019). It has recently been shown that genomic instability, in the form of unrepaired DNA double-strand breaks or micronuclei disruption can trigger STING-dependent anti-tumour responses. For example, use of chemotherapeutics can lead to higher levels of aberrant DNA in the cytosol which in turn can trigger cancer cell intrinsic STING signalling leading to anti-tumour immunity. Indeed the efficacy of the commonly used chemotherapeutic drug 5-fluorouracil (5-FU) was recently shown to depend on anti-tumor immunity triggered by the activation of cancer-cell intrinsic STING (Tian J et al. 5-Fluorouracil efficacy requires anti-tumor immunity triggered by cancer-cell-intrinsic STING. EMBO J. 40: e106065 (2021). In addition, PARP inhibitor-induced STING pathway activation and anti-tumor immune responses have been demonstrated in multiple tumour models, providing rationale for exploiting combinations of PARP inhibitors with immunotherapies for improved therapeutic efficacy. For example the PARP inhibitor Olaparib was also recently shown to induce synthetic lethal effects in combination with a synthetic cyclic dinucleotide STING agonist in DNA damage repair deficient cancer cells and a BRCA-deficient breast cancer model (Pantelidou C et al. STING agonism enhances anti-tumor immune responses and therapeutic efficacy of PARP inhibition in BRCA-associated breast cancer. bioRxiv (2021). The authors hypothesize that STING agonism can enhance the therapeutic efficacy of PARP inhibitors in BRCA-associated triple-negative breast cancer (TNBC).
Overall, modulation of nucleic acid sensing pathways via multiple mechanisms has been shown to promote anti-tumour efficacy in a variety of cell and animal models thus demonstrating therapeutic potential for augmenting efficacy of immunotherapies and overcoming resistance to immune checkpoint blockade.
Poly-ADP-ribose polymerase 7 (PARP7, TIPARP, ARTD14), a member of the wider PARP enzyme family, modulates protein function by using nicotinamide adenine dinucleotide (NAD+) as a substrate to transfer an ADP-ribose monomer onto specific amino acid acceptor residues of target proteins (Gomez A et al. Characterisation of TCDD-inducible poly-ADP-ribose polymerase (TIPARP/ARTD14) catalytic activity. Biochemical Journal. 475: 3827-3846, (2018)). PARP7 catalyses mono-ADP ribosylation (MARylation) of its target substrates and as such is a member of the mono(ADP-ribosyl) transferase (MART) enzymes, a subclass of the PARP family of enzymes (reviewed in-Challa L. et al. MARTs and MARylation in the Cytosol: Biological Functions, Mechanisms of Action, and Therapeutic Potential. Cells 10, 313 (2021)). PARP7 is a target gene of the Aryl Hydrocarbon Receptor (AHR) which is a ligand-activated transcription factor and member of the basic helix-loop-helix/Per-AHR nuclear translocator (ARNT)-Sim (PAS) protein family which plays a central role in controlling immune responses. Therefore, PARP7 has emerged as a critical regulator of the innate immune response. The PARP7 gene is amplified in a number of cancers, notably those of the upper aerodigestive tract (Vasbinder, M. M. et al. RBN-2397: A First-in-class PAPR7 inhibitor targeting a newly discovered cancer vulnerability in stress-signalling pathways. Cancer Res. 80:16 suppl DDT02-01, (2020)). PARP7 has been reported to ADP ribosylate and inactivate the kinase domain of TBK1 resulting in suppression of a central pathway for interferon production (Yamada T et al. Constitutive aryl hydrocarbon receptor signalling constrains type I interferon-mediated antiviral innate defence. Nature Immunol. 17: 687-694, (2016)). The possibility of using PARP7 inhibitors in cancer therapy, especially in the treatment of lung squamous cell carcinoma, has been described in WO 2016/116602. The discovery of a potent and selective inhibitor of PARP7, RBN-2397 has been recently reported (Vasbinder, M. M. et al. RBN-2397: A First-in-class PAPR7 inhibitor targeting a newly discovered cancer vulnerability in stress-signalling pathways. Cancer Res. 80:16 suppl DDT02-01, (2020); Gozgit J et al. PARP7 negatively regulates the type I interferon response in cancer cells and its inhibition leads to tumour regression. Cancer Res. 80:16 suppl 3405, (2020); Gozgit J et al. PARP7 negatively regulates the type I interferon response in cancer cells and its inhibition triggers antitumor immunity. Cancer Cell 39: 1-13, 2021). RBN-2397 potently inhibited proliferation in cancer cell lines with high baseline expression of interferon stimulated genes and restored type I interferon responses both in vitro and in vivo resulting in tumour regression and establishment of specific anti-tumour immunity in animal models. WO 2019/212937 describes pyridazinone compounds as inhibitors of PARP7 for use in the treatment of cancer. The monocyclic pyridazinone ring is claimed as an essential feature in the interaction with the PARP7 target. These observations provide a rational basis for generating novel agents to inhibit PARP7 and induce therapeutic anti-tumour responses.
There is also an established and growing literature highlighting key roles of PARP7 in other diseases:
The inactive PARP family member, PARP13, which plays a key role in regulating the antiviral innate immune response, is a major substrate of PARP7 (Rodriguez, K et al. Chemical genetics and proteome-wide site mapping reveal cysteine MARylation by PARP-7 on immune-relevant protein targets. Elife. 10:e60480, (2021)). PARP13 is preferentially MARylated on cysteine residues in its RNA binding zinc finger domain. PARP13 stimulates the interferon response in response to influenza A viral infection via direct activation of the cytosolic nucleic acid sensor RNA helicase RIG-I. This interaction is dependent on the finger domains of PARP13. Hence Cys MARylation of PARP13 by PARP7 could potentially disrupt the interaction between PARP13 and RIG-I thus regulating its antiviral and immune regulatory roles.
In addition, PARP7 promotes influenza A virus infection by ADP-ribosylating TBK1, which inhibits type I IFN (IFN-I) production (Yamada T. et al. Constitutive aryl hydrocarbon receptor signaling constrains type-I-interferon-mediated antiviral innate defense. Nat. Immunol. 17: 687-694, (2016)). The same study found that constitutive AHR signalling negatively regulated the type I interferon (IFN-I) response during infection with various types of virus; therefore revealing the physiological importance of endogenous activation of AHR signalling in shaping the IFN-I-mediated innate response and, further, suggesting that the AHR-PARP7 axis is a potential therapeutic target for controlling antiviral responses.
More recently (Heer C. et al. Coronavirus infection and PARP expression dysregulate the NAD Metabolome: an actionable component of innate immunity. J Biol Chem. 195, 17986-17996 (2020)) it has been shown that SARS-CoV-2 infection strikingly upregulates MARylating PARPs including PARP7. and induces the expression of genes encoding enzymes for salvage NAD synthesis from nicotinamide (NAM) and nicotinamide riboside (NR), while downregulating other NAD biosynthetic pathways. Furthermore, infection of mice with mouse hepatitis virus (MHV), a coronavirus (CoV), stimulated upregulation of downstream effector PARP7 via activation of the AHR. Knockdown of PARP7 reduced viral replication and increased interferon expression, suggesting that PARP7 functions in a proviral manner during MHV infection (Grunewald M. E. et al. Murine Coronavirus Infection Activates the Aryl Hydrocarbon Receptor in an Indoleamine 2,3-Dioxygenase-Independent Manner, Contributing to Cytokine Modulation and Proviral TCDD-Inducible-PARP Expression. J Virology 94: e01743-19 (2020). The AhR is also overexpressed following coronavirus infection, including SARS-CoV-2 and, as it regulates PARP gene expression, the latter is likely to be activated in COVID-19 (Badawy A. Immunotherapy of COVID-19 with poly (ADP-ribose) polymerase inhibitors: starting with nicotinamide. Bioscience Reports. 40: BSR20202856 (2020)). Therefore, given its key role in the innate immune system, PARP7 inhibition could be used to improve the outcome of patients with a wide variety of infectious diseases including those driven by viral infection.
PARP7 affects neural progenitor cell proliferation and migration, and its loss leads to aberrant organization of the mouse cortex during development (Grimaldi G et al. Loss of Tiparp Results in Aberrant Layering of the Cerebral Cortex. ENeuro 6(6) 0239-19.2019). PARP7 is highly expressed in the brain with increased expression reported in a range of neurological diseases. PARP7 was identified as a highly upregulated protein following trace fear conditioning and in neurologic disorders, such as epilepsy (Dachet et al. Predicting novel histopathological microlesions in human epileptic brain through transcriptional clustering. Brain 138:356-370, (2015)). In an integrated multi-cohort transcriptional meta-analysis of neurodegenerative diseases including Alzheimers Disease, Amyotrophic Lateral Sclerosis, Parkinsons Disease and Huntingdons Disease, PARP7 was shown to be strongly upregulated (Li et al. Integrated multi-cohort transcriptional meta-analysis of neurodegenerative diseases. Acta Neuropathol Commun 2:93 (2014)). The phenotype of the PARP7−/− mice and expression pattern suggests that alterations in PARP7 expression or function could increase susceptibility to a wide range of both developmental and degenerative neurologic diseases and that inhibitors may potentially show beneficial effects in these conditions.
It has recently been reported that STING is a critical regulator of nociception mediated through induction of type I interferon production and subsequent activation of type I interferon receptors on sensory neurons (Donnelly C R et al. STING controls nociception via type I interferon signalling in sensory neurons. Nature. 591: 275-280 (2021)). Mice lacking STING exhibit hypersensitivity to nociceptive stimuli whereas STING activation elicits marked antinociception in mice and non-human primates. PARP7 is a negative regulator of the STING pathway and inhibitors of PARP7 have been shown to activate this pathway. Such inhibitors may have utility as antinociceptive agents and the treatment of chronic pain conditions including cancer-associated pain and peripheral neuropathy.
In addition, there is therapeutic potential for use of a PARP7 inhibitor in canine cancer as notably recent data showed that intratumoral delivery of a STING agonist resulted in clinical responses in canine glioblastoma (Boudreau C E et al. Delivery of STING Agonist Results in Clinical Responses in Canine Glioblastoma. Clin Cancer Res (2021).
Having regard to the above, it is an aim of the present invention to provide PARP7 inhibitors, and in particular PARP7 inhibitors for use in medicine. It is a further aim to provide pharmaceutical compositions comprising such inhibitors, and in particular to provide compounds and pharmaceutical compositions for treating a cancer, an infectious disease, a central nervous system disease or disorder and other diseases, conditions and disorders. It is also an aim to provide methods of synthesis of the compounds.
Accordingly, the present invention provides a PARP7 inhibitor compound, which compound comprises the following formula:
wherein each X1 may be the same or different and is independently selected from C, N, O and S; each Y may be the same or different and is independently selected from C and N; Z1 is independently selected from C and N; each X1 may independently be unsubstituted, or may independently be substituted with H or a substituted or unsubstituted organic group; each Y may independently be unsubstituted, or may independently be substituted with H or a substituted or unsubstituted organic group; Z1 may independently be further substituted with H or a substituted or unsubstituted organic group; m may be 1, 2, 3 or 4; n may be 1, 2, or 3; the bonds between all of the atoms in ring A may independently be single bonds or double bonds provided that when X1 is O or S the bonds to that X1 are single bonds; the bonds between all of the atoms in ring B may independently be single bonds or double bonds provided that when X1 is O or S the bonds to that X1 are single bonds;
and wherein R1 may be attached to Z1 by a single bond or a double bond and is a substituent of formula:
wherein each Q may be the same or different an is independently selected from C, N, O and S; each Q may independently be attached to another Q, or to Z3, by a single bond or a double bond; each Q may independently be unsubstituted, or may independently be substituted by H or a substituted or unsubstituted organic group; two or more Q atoms may form a ring together with their substituents; p is a number from 2 to 8; each Z3 may be the same or different and is independently selected from C and N; each Z3 may independently be further substituted with H or a substituted or unsubstituted organic group; each X2 may be the same or different and is independently selected from C, N, O and S; r is a number from 1 to 5; s is independently a number from 1 to 5; wherein Q1 is selected from C, N, O and S and may be attached to Z3 and R4, by a single bond or a double bond and may be unsubstituted, or substituted by H or an organic group; and R4 is a substituted or unsubstituted organic group comprising a substituted or unsubstituted carbocyclic or heterocyclic ring; each bond in the ring comprised of Z3 and X2 atoms may independently be a double bond or a single bond, provided that when X2 is O or S the bonds to that X2 are single bonds; each R5 may be present or absent depending on the number of bonds to, and the valence of, the X2 atom attached to that R5; and wherein each R5 is independently selected from H or a substituted or unsubstituted organic group;
and wherein R2 may be attached to ring B by a single bond or a double bond and is a substituted or unsubstituted organic group;
and wherein R16 may be present or absent and when present is selected from H, a C1-C6 alkyl group or a linear or branched C1-C6 halogenated alkyl group.
Typically, if an R5 group is a substituent on a C atom, then that R5 may be selected from any substituent that R7 or R8 may be, and if an R5 group is a substituent on an N atom, then that R5 may be selected from any substituent that R6 or R9 may be.
In the present invention, both above and in the following, where a substituent is possible, but not depicted in a formula, the number of substituents borne by any atom is the number required to maintain the valency for that atom. For example, in the formula above, the groups X1 and Y may be unsubstituted or substituted. The substituents have not been shown explicitly in the formula since the number of such substituents (and their presence or absence) will depend on the number of bonds to, and the valence of, the X1 atom or Y atom comprising a substituent. In general, both above and in the following, where a substituent is possible, but not depicted in a formula, the number of substituents borne by any atom is the number required to maintain the valency for that atom. Similarly, in some cases a substituent has been depicted, but the number of such substituents (and their presence or absence) depends on the number of bonds to, and the valence of, the atom comprising the substituent. In those cases, both above and in the following, the number of substituents borne by the atom is again the number required to maintain the valency for that atom.
In the context of the present invention, maintaining the valency means ensuring that an atom has its normal (typically most common) valency in organic compounds (for example 2 for oxygen and sulphur, 3 for nitrogen and 4 for carbon). Nitrogen atoms may, in some instances, have 4 bonds, but in such cases they are typically positively charged such that the compound may have a counter-ion. Sulphur atoms may, in some instances, have a higher valency such as 6, for example when forming a sulphonyl group. Such compounds are also considered to be part of the invention. When there is a positive charge on a nitrogen, it will be clear that the nitrogen atom still maintains its normal valency of 3. For the avoidance of doubt, where the number of R groups may vary according to the choice of X, Y or Z group, it may vary as follows.
Each R5 may be the same or different, provided that for each X2: R5 is absent when X2 is N and is double bonded to a ring atom; one R5 is present when X2 is N and is not double bonded to a ring atom; one R5 is present when X2 is C and is double bonded to a ring atom; and two R5 are present when X2 is C and is not double bonded to a ring atom.
R16 is absent when the N to which it is attached in ring B is double bonded to a ring atom; R16 is present when the N is not double bonded to a ring atom.
Each R11 may be the same or different, provided that for each X4: R11 is absent when X4 is O or divalent S; R11 is absent when X4 is N and is double bonded to an adjacent atom; one R11 is present when X4 is N and is not double bonded to an adjacent atom; one R11 is present when X4 is C and is double bonded to an adjacent atom; two R11 are present when X4 is C and is not double bonded to an adjacent atom; and two R11 are present, each as double bonded O when X4 is hexavalent S.
R12 is absent when the Z6 to which it is attached is O or S; R12 is absent when the Z6 is N and is double bonded to a ring atom; R12 is present when the Z6 is N and is not double bonded to a ring atom; R12 is present when the Z6 is C and is double bonded to a ring atom; R12 is present when the Z6 is C and is single bonded to a ring atom and bears a further substituent.
In these compounds, and elsewhere herein, in some embodiments any R group (with the exception of R1) may form a ring with any other R group on an adjacent and/or proximal atom, although in most embodiments this is not preferred, except where explicitly stated. Thus, in some embodiments the following substituents may together form a ring: R5 with another R5; R5 with R4; R6 with another R6; R6 with R7; R7 with another R7; R8 with another R8; R8 with R9; R9 with another R9; R6 with R8; R6 with R11; and R11 with another R11. In the context of the present invention, an adjacent and/or proximal atom may mean another atom directly bonded to an atom (adjacent), or may be two atoms with only a single atom in between (proximal), or may mean two atoms close enough sterically to be capable of forming a ring (proximal). Preferably R groups attached to the same atom do not together form a ring, although this is not excluded.
In the present context the invention includes compounds in which a single R group on an atom, or two R groups on the same atom, form a group which is double bonded to that atom. Accordingly, an R group, or two R groups attached to the same atom, may together form a ═O group, or a ═C(R′)2 group (wherein each R′ group is the same or different and is H or an organic group, preferably H or a straight or branched C1-C6 alkyl group). This is more typical in cases where the R groups are attached to a C atom, such that together they form a C═O group or a C═C(R′)2 group. Thus is some cases a C ring atom in a ring may comprise a ═O group, as may any X, any Z, and/or and one or more of R2, R5, R7, R8, and R11.
In the present context, part of any structure present in brackets may be repeated the number of times given by the numbers next to the brackets (whether regular brackets or square brackets). For example, in the case of (C(R))0,1,2 or [C(R)]0,1,2 the C—R group may be absent, present once i.e. —C(R)—; or present twice i.e. —C(R)—C(R)—.
Further in the present context, where a structural component is depicted with a wavy line on a bond, that bond is the bond that attaches to another structural component of the compound.
In the context of the present invention, a compound is considered to be a PARP7 inhibitor if its presence is capable of preventing or reducing the ability of immobilised PARP7 to undergo auto-mono-ADP ribosylation (AutoMARylation) following incubation with biotinylated-NAD+ as compared to the same process in its absence. Typically, the compound is considered to be a PARP7 inhibitor if it has an IC50<10 μM in a suitable assay. A suitable assay may be conducted using 10-30 nM PARP7 (amino acids 456-657), 2 μM biotin-NAD assay solution in 20 mM HEPES (pH 7.5), 100 mM NaCl, 2 mM DTT, 0.1% BSA (w/v), 0.02% Tween (v/v) assay buffer. MARylation may take place for 2-3 h at room temperature and may be detected using a dissociation-enhanced lanthanide fluorescence immunoassay (DELFIA) readout. This assay format has been recently utilised for screening for modulators of PARP7 and other MonoPARP enzymes (Wigle T. et al. Forced Self-Modification Assays as a Strategy to Screen MonoPARP Enzymes. SLAS Discovery. 25; 241-252, (2020)). A particularly suitable assay is described in the Examples below.
In all of the embodiments of this invention (both above and below herein), the substituents (each of the R groups) are not especially limited, provided that they do not prevent the PARP7 inhibitory function from occurring. In all of the embodiments mentioned in connection with this invention, both above and in the following, the substituents are selected from H and an organic group. Thus, both above and in the following, the terms ‘substituent’ and ‘organic group’ are not especially limited and may be any functional group or any atom, especially any functional group or atom common in organic chemistry. Thus, ‘substituent’ and ‘organic group’ may have any of the following meanings.
The organic group may comprise any one or more atoms from any of groups IIIA, IVA, VA, VIA or VIIA of the Periodic Table, such as a B, Si, N, P, O, or S atom (e.g. OH, OR, NH2, NHR, NR2, SH, SR, SO2R, SO3H, PO4H2) or a halogen atom (e.g. F, Cl, Br or I) where R is a linear or branched lower hydrocarbon (1-6 C atoms) or a linear or branched higher hydrocarbon (7 C atoms or more, e.g. 7-40 C atoms).
The organic group preferably comprises a hydrocarbon group. The hydrocarbon group may comprise a straight chain, a branched chain or a cyclic group. Independently, the hydrocarbon group may comprise an aliphatic or an aromatic group. Also independently, the hydrocarbon group may comprise a saturated or unsaturated group.
When the hydrocarbon comprises an unsaturated group, it may comprise one or more alkene functionalities and/or one or more alkyne functionalities. When the hydrocarbon comprises a straight or branched chain group, it may comprise one or more primary, secondary and/or tertiary alkyl groups.
When the hydrocarbon comprises a cyclic group, it may comprise an aromatic ring, a non-aromatic ring, an aliphatic ring, a heterocyclic group, and/or fused ring derivatives of these groups. The ring may be fully saturated, partially saturated, or fully unsaturated. The cyclic group may thus comprise a benzene, naphthalene, anthracene, phenanthrene, phenalene, biphenylene, pentalene, indene, as-indacene, s-indacene, acenaphthylene, fluorene, fluoranthene, acephenanthrylene, azulene, heptalene, pyrrole, pyrazole, imidazole, 1,2,3-triazole, 1,2,4-triazole, tetrazole, pyrrolidine, furan, tetrahydrofuran, 2-aza-tetrahydrofuran, 3-aza-tetrahydrofuran, oxazole, isoxazole, furazan, 1,2,4-oxadiazol, 1,3,4-oxadiazole, thiophene, isothiazole, thiazole, thiolane, pyridine, pyridazine, pyrimidine, pyrazine, piperidine, 2-azapiperidine, 3-azapiperidine, piperazine, pyran, oxetan-2-yl, oxetan-3-yl, tetrahydropyran, 2-azapyran, 3-azapyran, 4-azapyran, 2-aza-tetrahydropyran, 3-aza-tetrahydropyran, morpholine, thiopyran, 2-azathiopyran, 3-azathiopyran, 4-azathiopyran, thiane, indole, indazole, benzimidazole, 4-azaindole, 5-azaindole, 6-azaindole, 7-azaindole, isoindole, 4-azaisoindole, 5-azaisoindole, 6-azaisoindole, 7-azaisoindole, indolizine, 1-azaindolizine, 2-azaindolizine, 3-azaindolizine, 5-azaindolizine, 6-azaindolizine, 7-azaindolizine, 8-azaindolizine, 9-azaindolizine, purine, carbazole, carboline, benzofuran, isobenzofuran, benzothiophene, isobenzothiophene, quinoline, cinnoline, quinazoline, quinoxaline, 5-azaquinoline, 6-azaquinoline, 7-azaquinoline, isoquinoline, phthalazine, 6-azaisoquinoline, 7-azaisoquinoline, pteridine, chromene, isochromene, acridine, phenanthridine, perimidine, phenanthroline, phenoxazine, xanthene, phenoxanthiin, and/or thianthrene, as well as regioisomers of the above groups. These groups may generally be attached at any point in the group, and also may be attached at a hetero-atom or at a carbon atom. In some instances particular attachment points are preferred, such as at 1-yl, 2-yl and the like, and these are specified explicitly where appropriate. All tautomeric ring forms are included in these definitions. For example pyrrole is intended to include 1H-pyrrole, 2H-pyrrole and 3H-pyrrole.
The number of carbon atoms in the hydrocarbon group is not especially limited, but preferably the hydrocarbon group comprises from 1-40 C atoms. The hydrocarbon group may thus be a lower hydrocarbon (1-6 C atoms) or a higher hydrocarbon (7 C atoms or more, e.g. 7-40 C atoms). The lower hydrocarbon group may be a methyl, ethyl, propyl, butyl, pentyl or hexyl group or regioisomers of these, such as isopropyl, isobutyl, tert-butyl, etc. The number of atoms in the ring of the cyclic group is not especially limited, but preferably the ring of the cyclic group comprises from 3-10 atoms, such as 3, 4, 5, 6, 7, 8, 9 or 10 atoms.
The groups comprising heteroatoms described above, as well as any of the other groups defined above, may comprise one or more heteroatoms from any of groups IIIA, IVA, VA, VIA or VIIA of the Periodic Table, such as a B, Si, N, P, O, or S atom or a halogen atom (e.g. F, Cl, Br or I). Thus the substituent may comprise one or more of any of the common functional groups in organic chemistry, such as hydroxy groups, carboxylic acid groups, ester groups, ether groups, aldehyde groups, ketone groups, amine groups, amide groups, imine groups, thiol groups, thioether groups, sulphate groups, sulphonic acid groups, sulphonyl groups, and phosphate groups etc. The substituent may also comprise derivatives of these groups, such as carboxylic acid anhydrides and carboxylic acid halides.
In addition, any substituent may comprise a combination of two or more of the substituents and/or functional groups defined above.
The invention will now be described in more detail with reference to some of the preferred embodiments.
The rings A and B of the compounds of the present invention form a bicyclic fused ring structure (which may comprise further fused rings when the substituents on either ring themselves form a ring). Each of rings A and B are not necessarily limited, provided that they do not prevent the PARP7 inhibitory function from occurring. Ring A and ring B may independently be comprised of an aromatic ring, a non-aromatic ring, an aliphatic ring, and/or a heterocyclic ring. The rings may be fully saturated, partially saturated, or fully unsaturated. Each ring may thus independently comprise a benzene, naphthalene, anthracene, phenanthrene, phenalene, biphenylene, pentalene, indene, as-indacene, s-indacene, acenaphthylene, fluorene, fluoranthene, acephenanthrylene, azulene, heptalene, pyrrole, pyrazole, imidazole, 1,2,3-triazole, 1,2,4-triazole, tetrazole, pyrrolidine, furan, tetrahydrofuran, 2-aza-tetrahydrofuran, 3-aza-tetrahydrofuran, oxazole, isoxazole, furazan, 1,2,4-oxadiazol, 1,3,4-oxadiazole, thiophene, isothiazole, thiazole, thiolane, pyridine, pyridazine, pyrimidine, pyrazine, piperidine, 2-azapiperidine, 3-azapiperidine, piperazine, pyran, tetrahydropyran, 2-azapyran, 3-azapyran, 4-azapyran, 2-aza-tetrahydropyran, 3-aza-tetrahydropyran, morpholine, thiopyran, 2-azathiopyran, 3-azathiopyran, 4-azathiopyran, thiane, indole, indazole, benzimidazole, 4-azaindole, 5-azaindole, 6-azaindole, 7-azaindole, isoindole, 4-azaisoindole, 5-azaisoindole, 6-azaisoindole, 7-azaisoindole, indolizine, 1-azaindolizine, 2-azaindolizine, 3-azaindolizine, 5-azaindolizine, 6-azaindolizine, 7-azaindolizine, 8-azaindolizine, 9-azaindolizine, purine, carbazole, carboline, benzofuran, isobenzofuran, benzothiophene, isobenzothiophene, quinoline, cinnoline, quinazoline, quinoxaline, 5-azaquinoline, 6-azaquinoline, 7-azaquinoline, isoquinoline, phthalazine, 6-azaisoquinoline, 7-azaisoquinoline, pteridine, chromene, isochromene, acridine, phenanthridine, perimidine, phenanthroline, phenoxazine, xanthene, phenoxanthiin, and/or thianthrene, as well as regioisomers of the above groups. These rings may generally be substituted at any point in the group, and also may be substituted at a hetero-atom or at a carbon atom. All tautomeric ring forms are included in these definitions. For example pyrrole is intended to include 1H-pyrrole, 2H-pyrrole and 3H-pyrrole.
In typical embodiments, the invention provides a compound as defined above, wherein ring B is selected from the following:
wherein each Y may independently be selected from C and N; each X1 may independently be selected from C, N, O and S; the bonds between all of the atoms in ring B may independently be single bonds or double bonds provided that when X1 is O or S the bonds to that X1 are single bonds; wherein each X1 may independently be unsubstituted, or substituted by H or a substituted or unsubstituted organic group; and wherein R16 may be present or absent and is as defined herein.
In some preferred embodiments, ring B may be selected from the following:
wherein Y, X1 and R16 are as defined anywhere herein, and the bonds between all of the atoms in ring B may independently be single bonds or double bonds provided that when X1 is O or S the bonds to that X1 are single bonds.
In further preferred embodiments, ring B may be selected from the following:
wherein R6 and R7 are independently selected from H or a substituted or unsubstituted organic group and R16 is as defined herein.
In further preferred embodiments, and independently from ring B, ring A may be selected from the following:
wherein Y, X1, Z1 and R1 are as defined herein.
In yet further preferred embodiments, ring A may be selected from the following:
wherein R1 is as defined herein, and R8 and R9 are independently selected from H and a substituted or unsubstituted organic group.
In preferred embodiments, and independently from ring A and ring B, R1 may be selected from the following:
wherein Q, Q1, p, Z3, X2, R4 and R5 are as defined herein.
In still further preferred embodiments, R1 may be selected from the following:
wherein Q, p, R7 and R4 are as defined herein.
In some preferred embodiments, the linking group -(Q)p- may be selected from the following:
wherein each X3 may be the same or different and is independently selected from C, N, O and S; when C or N, each X3 may independently be unsubstituted or substituted with H or a substituted or unsubstituted organic group; each X4 may be the same or different and is independently selected from C, N, O and S; each Z4 may be the same or different and is independently selected from C and N; the bonds between all of the atoms any ring may independently be single bonds or double bonds provided that when X3 is O or S the bonds to that X3 are single bonds; R11 may be present or absent depending on the number of bonds and the valence of the X4 atom comprising that R1; and wherein each R1 is independently selected from H or a substituted or unsubstituted organic group; and wherein R15 is selected from H, a linear or branched C1-C6 alkyl group or a linear or branched C1-C6 halogenated alkyl group; and wherein Z5 may be attached via a single bond or a double bond and is selected from the following:
wherein each R3 may be the same or different and is independently selected from H and a substituted or unsubstituted organic group;
and wherein p and Z3 are as defined herein.
In still further preferred embodiments, the linking group -(Q)p- may be selected from the following:
wherein Z3, R6, R8 and R11 are as defined herein.
In preferred embodiments of the present invention, R4 may be attached via a single bond or a double bond, and may be selected from the following:
wherein each X5 may be the same or different and is independently selected from C, N, O and S; when C or N, each X5 may independently be unsubstituted or substituted with H or a substituted or unsubstituted organic group; each Z6 may be the same or different and is independently selected from C, N, O and S; the bonds between all of the atoms any ring may independently be single bonds or double bonds provided that when X5 or Z6 is O or S the bonds to that X5 or Z6 are single bonds; R12 may be present or absent depending on the number of bonds and the valence of the Z6 atom comprising that R12; wherein if present R12 is independently selected from H or a substituted or unsubstituted organic group; wherein each Z6 may independently be further substituted with H or a substituted or unsubstituted organic group; and wherein R8 and R11 are as defined herein.
In some preferred embodiments, R4 may be selected from the following:
wherein R6, R7 and R12 are each independently H or a substituted or unsubstituted organic group.
Q1 may be present or absent and it is preferred that Q1 is absent so that R4 is directly attached to Z3. When present, Q1 is typically O, S, CH2 or NH.
In preferred embodiments of the invention, R2 may be attached via a single bond or a double bond and is selected from the following:
wherein each R3 may be the same or different and is independently selected from H and a substituted or unsubstituted organic group.
In some preferred embodiments R1 may be selected from the following:
wherein R6, R7, R8, R11 and R12 are as defined herein.
The present invention further provides a PARP7 inhibitor compound, which compound comprises the following formula:
wherein each X1 may be the same or different and is independently selected from C, N, O and S; each Y may be the same or different and is independently selected from C and N; Z1 is independently selected from C and N; each X1 may independently be unsubstituted, or may independently be substituted with H or a substituted or unsubstituted organic group; each Y may independently be unsubstituted, or may independently be substituted with H or a substituted or unsubstituted organic group; Z1 may independently be further substituted with H or a substituted or unsubstituted organic group; m may be 1, 2, or 3; n may be 1, 2 or 3, preferably 1 or 2; the bonds between all of the atoms in ring A may independently be single bonds or double bonds provided that when X1 is O or S the bonds to that X1 are single bonds; the bonds between all of the atoms in ring B may independently be single bonds or double bonds provided that when X1 is O or S the bonds to that X1 are single bonds; and R2 and R16 are as defined herein;
and wherein R1 may be attached to Z1 by a single bond or a double bond and is a substituent of formula:
wherein L is a group selected from any of the following:
wherein each Q may be the same or different and is independently selected from C, N, O and S; each Q may independently be attached to another Q, or to Z3, by a single bond or a double bond; each Q may independently be unsubstituted, or may independently be substituted by H or a substituted or unsubstituted organic group; each R8 is independently selected from H and a substituted or unsubstituted organic group; R11 may be present or absent depending on the number of bonds and the valence of the Q atom comprising that R11; and each R11 is independently selected from H and a substituted or unsubstituted organic group; and wherein each Z3 may be the same or different and is independently selected from C and N; each X2 may be the same or different and is independently selected from C, N, O and S; r is a number from 1 to 3; and s is independently a number from 1 to 3; wherein Q1 is selected from C, N, O and S and may be attached to Z3 and R4, by a single bond or a double bond and may be unsubstituted, or substituted by H or an organic group; each bond in the ring comprised of Z3 and X2 atoms may independently be a double bond or a single bond provided that when X2 is O or S the bonds to that X2 are single bonds; each R5 may be present or absent depending on the number of bonds to, and the valence of, the X2 atom attached to that R5; and wherein each R5 is independently selected from H or a substituted or unsubstituted organic group;
and wherein R4 is a group selected from any of the following:
and wherein each R6 is independently selected from H and a substituted or unsubstituted organic group; and wherein R12 is independently selected from H or a substituted or unsubstituted organic group and preferably a group selected from: —H, —CH3, —CN, —CF3, —CHF2, —CH2F, —OCF3, —OMe, —CH2CF3, —CF2CH3, —OCHF2, —OCH2F, —F, —Cl, —Br, —I, —SO2Me, —CONHMe, t-Bu, cyclopropyl and
In a compound according to this formula it is preferred that R1 has any of the following structures:
wherein L, Z3, X2, Q1, R4 and R are as defined herein.
Preferably, R1 has any of the following structures:
wherein L, R4 and R7 are as defined herein.
Advantageously, the compounds according to the invention may comprise the following general formula:
wherein X1, Z1, R1, R16, m and n are as defined herein. Typically, m is 1,2 or 3; n is 1,2 or 3; m is preferably 1 or 2; and n is preferably 1 or 2, most preferably 2.
The invention will now be described in more detail. Firstly, a number of typical general structures of the compounds of the invention will be described.
The following are a number of typical general structures of the compounds of the invention.
wherein R1, R6, R7, R8, R9 and R16 are as defined herein.
The following are some preferred general structures according to the invention:
wherein R6, R7, R8, R11, R12 and R16 are as defined herein.
The R groups referred to in the compounds and structures herein will now be described in more detail.
As has been mentioned, the number of R substituents on an X, Y, Z or a ring atom will depend on its valency. Thus, it will be apparent in all of the embodiments of the invention, both above and below, that when an X, Y or Z, or a ring atom has three ring bonds (either 3 single bonds or a single bond and a double bond), it will have no substituents if it is N and 1 substituent (H or an organic group as defined herein) if it is C, and when X, Y or Z, or a ring atom has two ring bonds (2 single bonds), it will have 1 substituent (H or an organic group as defined herein) if it is N and 2 substituents if it is C (each independently chosen from H or an organic group as defined herein). Of course, if X or Z is O there will not be any substituents. If X or Z is S it may have no substituents, or it may be a sulphonyl group.
As has been mentioned, in all of the embodiments of this invention (both above and below herein), the substituent is not especially limited, provided that it does not prevent the PARP7 inhibitory function from occurring. However, in typical embodiments, the substituents may be selected independently as follows.
R5, R7, R8, R11 and R12 are typically each independently selected from H and a group selected from the following groups:
More typically, R5 is independently selected from H, deuterium, a halogen (such as —F, —Cl, —Br, and —I, preferably F), a substituted or unsubstituted C1-C6 alkyl group, a substituted or unsubstituted linear or branched C1-C6 halogenated alkyl group, an —OH group or a substituted or unsubstituted linear or branched C1-C6 alcohol group, an —NH2 group or a substituted or unsubstituted C1-C6 amino group and a substituted or unsubstituted C1-C6 alkoxy group; or wherein there are two R5 groups on the same atom which together form a carbonyl group.
More typically, R7 and R8 are each independently selected from H, deuterium, a halogen (such as —F, —Cl, —Br, and —I), a substituted or unsubstituted C1-C6 alkyl or cycloalkyl group, a substituted or unsubstituted linear or branched C1-C6 halogenated alkyl group, an —OH group or a substituted or unsubstituted linear or branched C1-C6 alcohol group, an —NH2 group or a substituted or unsubstituted C1-C6 amino group, a substituted or unsubstituted C1-C6 alkoxy group, and a nitrile group; or wherein there are two R7 or R8 groups on the same atom which together form a carbonyl group.
More typically R11 is selected from H, deuterium, a halogen (such as —F, —Cl, —Br, and —I, preferably —F), a substituted or unsubstituted C1-C6 alkyl group, a substituted or unsubstituted linear or branched C1-C6 halogenated alkyl group (preferably CF3), an —NH2 group or a substituted or unsubstituted C1-C6 amino group, an —OH group or a substituted or unsubstituted linear or branched C1-C6 alcohol group and a substituted or unsubstituted C1-C6 alkoxy group.
More typically, R12 is selected from —H, —CH3, —CN, —CF3, —CHF2, —CH2F, —OCF3, —OMe, —CH2CF3, —CF2CH3, —OCHF2, —OCH2F, —F, —Cl, —Br, —I, —SO2Me, —CONHMe, t-Bu, cyclopropyl and
Typically, R3, R6, and R9 are each independently selected from H and a group selected from the following groups:
More typically, R3, R6 and R9 are each independently selected from H, a substituted or unsubstituted C1-C6 alkyl group or a substituted or unsubstituted linear or branched C1-C6 halogenated alkyl group.
Preferably, R16 is absent or selected from H, a C1-C3 alkyl group and a C1-C3 halogenated alkyl group. More preferably, R16 is H.
In some embodiments, the present invention provides a PARP7 inhibitor compound which comprises a formula selected from one of the following:
The compounds of the present invention have been described in detail above in terms of their structures. For the avoidance of doubt, any compounds for use in the invention may comprise compounds or compositions in accordance with their structure as follows:
In the case of compound 116, this is the active enantiomer, eluted as a first fraction when a racemic mixture of the two enantiomers is applied to a Daicel CHIRALPAK chiral chromatography column.
In the case of compounds 33, 62, 63 and 273, these are each the active enantiomer, eluted as a second fraction when a racemic mixture of the two enantiomers is applied to a Daicel CHIRALPAK chiral chromatography column.
In the case of the following pairs of compounds: 64 and 65, 70 and 71, 72 and 73, 75 and 76, 85 and 86, 87 and 88, 89 and 90, 119 and 120, 122 and 123, 129 and 130, 137 and 138, 142 and 143, 148 and 149, 151 and 152, 155 and 156, 160 and 161, 162 and 163, 168 and 169, 174 and 175, 176 and 177, 178 and 179, 185 and 186, 187 and 188, 189 and 190,201 and 202, 209 and 210, 211 and 212, 221 and 222, 223 and 224, 243 and 244, 245 and 246, 248 and 249, 250 and 251, 253 and 254, 255 and 256, 258 and 259, 262 and 263, 264 and 265, 266 and 267, 274 and 275, 278 and 279, 280 and 281, 283 and 284, 286 and 287, 288 and 289, 291 and 292, 293 and 294, 297 and 298, 304 and 305, 306 and 307, 308 and 309, 310 and 311, 312 and 313, 318 and 319, 321 and 322, 323 and 324, 325 and 326, 327 and 328, 329 and 330, 331 and 332, 335 and 336, 338 and 339, 342 and 343, 344 and 345, 347 and 348, 349 and 350, 351 and 352, 353 and 354, 355 and 356, 365 and 366, 368 and 389, 370 and 371, 372 and 373, 374 and 375, 376 and 377, 386 and 387, 388 and 389, 392 and 393, 395 and 396, 397 and 398, 399 and 400, 405 and 406,411 and 412, 414 and 415, 416 and 417, 418 and 419, 420 and 421, 422 and 423, 426 and 427, 429 and 430, 431 and 432, 435 and 436, 437 and 438, 439 and 440, 442 and 443, 444 and 445, 448 and 449, 450 and 451, 452 and 453, 454 and 455, 456 and 457, 458 and 459, 460 and 461, 462 and 463, 464 and 465, 466 and 467, 468 and 469, 472 and 473, 474 and 475, 476 and 477, 479 and 480, 481 and 482, 483 and 484, 485 and 486, 490 and 491, 492 and 493, 494 and 495, 496 and 497, 498 and 499, and 500 and 501; these are each a pair of enantiomers, eluted as first and second fractions respectively, when a racemic mixture of the two enantiomers is applied to a Daicel CHIRALPAK chiral chromatography column.
The compounds described herein may be provided for use in medicine. In the context of the present invention, the medicinal use is not especially limited, provided that it is a use which is facilitated by the PARP7 inhibitory effect of the compound. Thus, the compounds of the invention may be for use in any disease, condition or disorder that may be prevented, ameliorated or treated using a PARP7 inhibitor. Typically, this comprises a disease condition and/or a disorder selected from: a cancer, an infectious disease, a central nervous system disease or disorder, and a pain condition.
When the disease, condition or disorder is a cancer, it is not especially limited, provided that the cancer is one which may be treated, prevented or ameliorated by using a PARP7 inhibitor. Thus the cancer may be a cancer selected from: a solid or liquid tumour including cancer of the eye, brain (such as gliomas, glioblastomas, medullablastomas, craniopharyngioma, ependymoma, and astrocytoma), spinal cord, kidney, mouth, lip, throat, oral cavity, nasal cavity, small intestine, colon, parathyroid gland, gall bladder, head and neck, breast, bone, bile duct, cervix, heart, hypopharyngeal gland, lung, bronchus, liver, skin, ureter, urethra, testicles, vagina, anus, laryngeal gland, ovary, thyroid, oesophagus, nasopharyngeal gland, pituitary gland, salivary gland, prostate, pancreas, adrenal glands; an endometrial cancer, oral cancer, melanoma, neuroblastoma, gastric cancer, an angiomatosis, a hemangioblastoma, a pheochromocytoma, a pancreatic cyst, a renal cell carcinoma, Wilms' tumour, squamous cell carcinoma, sarcoma, osteosarcoma, Kaposi sarcoma, rhabdomyosarcoma, hepatocellular carcinoma, PTEN Hamartoma-Tumor Syndromes (PHTS) (such as Lhermitte-Duclos disease, Cowden syndrome, Proteus syndrome, and Proteus-like syndrome), leukaemias and lymphomas (such as acute lymphoblastic leukaemia, chronic lymphocytic leukaemia, acute myelogenous leukaemia, chronic myelogenous leukaemia, hairy cell leukaemia, T-cell prolymphocytic leukemia (T-PLL), large granular lymphocytic leukemia, adult T-cell leukemia, juvenile myelomonocytic leukaemia, Hodgkin lymphoma, non-Hodgkin lymphoma, mantle lymphoma, follicular lymphoma, primary effusion lymphoma, AIDS-related lymphoma, Hodgkin lymphoma, diffuse B cell lymphoma, Burkitt lymphoma, and cutaneous T-cell lymphoma), preferably wherein the cancer is a cancer selected from oesaphageal, head and neck, non-small cell lung cancer, squamous cell cancer of the lung, breast, acute myeloid leukemia (AML), a small-cell lung cancer, a melanoma, an ovarian cancer, a colorectal cancer, a pancreatic cancer, an endometrial cancer, and a skin papilloma.
When the disease is an infectious disease, it is not especially limited, provided that the disease is one which may be treated, prevented or ameliorated by using a PARP7 inhibitor. However, typically the infectious disease is selected from a bacterial infection and a viral infection, preferably a respiratory infection, immune system infection, gut infection and sepsis. Such viral respiratory infections include influenza and coronavirus infections, particularly influenza A and SARS-CoV-2 infections.
When the disease, condition or disorder is a central nervous system disease, condition or disorder, it is not especially limited, provided that the disease, condition or disorder is one which may be treated, prevented or ameliorated by using a PARP7 inhibitor. However, the central nervous system disease, condition or disorder is typically selected from amyotrophic lateral sclerosis (AML), Huntington's disease, Alzheimer's disease, pain, a psychiatric disorder, multiple sclerosis, Parkinson's disease, and HIV related neurocognitive decline.
When the disease, condition or disorder is a pain condition it is not especially limited, provided that the condition is one which may be treated, prevented or ameliorated by using a PARP7 inhibitor. Typically, the pain condition is nociceptive pain or neuropathic pain and may be a chronic pain condition such as cancer-associated pain and peripheral neuropathy.
The present invention also provides a pharmaceutical composition comprising a compound as defined above. Whilst the pharmaceutical composition is not especially limited, typically the composition further comprises a pharmaceutically acceptable additive and/or excipient. In the pharmaceutical composition, the compound as defined above may be present in the form described above, but may alternatively be in a form suitable for improving bioavailability, solubility, and/or activity, and/or may be in a form suitable for improving formulation. Thus, the compound may be in the form of a pharmaceutically acceptable salt, hydrate, acid, ester, or other alternative suitable form. Typically, the composition is for treating a disease, condition or disorder as defined above. In some instances, the compound may be present in the composition as a pharmaceutically acceptable salt, or other alternative form of the compound, in order to ameliorate pharmaceutical formulation.
In some embodiments the pharmaceutical composition is a composition for treating a cancer, further comprising a further agent for treating cancer. The further agent for treating cancer is not especially limited, provided that it affords some utility for cancer treatment. However, typically the further agent for treating cancer is selected from anti-microtubule agents, platinum coordination complexes, alkylating agents, antibiotic agents, topoisomerase II inhibitors, antimetabolites, topoisomerase I inhibitors, senolytic agents, hormones and hormone analogues, signal transduction pathway inhibitors, DNA damage repair pathway inhibitors, non-receptor tyrosine kinase angiogenesis inhibitors, immunotherapeutic agents (such as an anti-tumour vaccine, an oncolytic virus, an immune stimulatory antibody such as anti-CTLA4, anti-PD1, anti-PDL-1, anti-OX40, anti-41BB, anti-CD27, anti-CD40, anti-LAG3, anti-TIM3, and anti-GITR, a novel adjuvant, a peptide, a cytokine, a chimeric antigen receptor T cell therapy (CAR-T), a small molecule immune modulator such as an IDO or TDO inhibitor or a pattern recognition receptor agonist such as a STING, TLR-9 or RIG-I Helicase agonist, tumour microenvironment modulators, and anti-angiogenic agents), receptor tyrosine kinase inhibitors, cell growth inhibitors such as Ras and Raf inhibitors, proapoptotic agents and cell cycle signalling inhibitors.
In still further embodiments the invention provides a pharmaceutical kit for treating a cancer, which pharmaceutical kit comprises:
Further provided by the invention is a method of treating a disease and/or a condition and/or a disorder, which method comprises administering to a patient (or subject) a compound, or a composition, or a kit as defined above. The method is typically a method for treating any disease condition or disorder mentioned herein. In typical embodiments, the method is a method for treating a cancer. Preferably such a method comprises administering to a patient (or subject) a compound or a composition as defined above and a further agent for treating cancer as defined above. The compound or composition and the further agent may administered simultaneously, sequentially or separately, depending upon the agents and patients involved, and the type of cancer indicated.
Typically, in all embodiments of the invention, both above and below, the patient (or subject) is an animal, typically a mammal, including canines and felines, and more typically a human.
Further provided by the invention is a method of synthesis of a compound as defined above, which method comprises conducting a reaction between (i) a first reactant comprising rings A and B bearing a portion of substituent group R1 and (ii) a second reactant comprising the remainder of substituent group R1 so as to form the PARP7 inhibitor compound.
In one typical method the first reactant comprises a compound of general formula:
and the second reactant comprises a compound of general formula:
wherein R13 and R14 are each independently substituent groups which are removed during the reaction; and wherein X1, Y, Z1, Z2, R2, R4, R5, Q, m, n and p are as defined herein.
In typical embodiments, this method of synthesis is carried out by reacting under conditions suitable for an amide formation, nucleophilic displacement or Michael addition reaction. The skilled person may select the reaction conditions, with reference to known synthesis techniques depending on the appropriate starting materials. In some embodiments, the method comprises one or more additional substitution steps. Exemplary syntheses are shown in the Examples herein Typically, the above formulae (and all formulae herein) are shown in non-stereoisomeric form. For the avoidance of doubt, throughout the present disclosure a single formula is intended to represent all possible stereoisomers of a particular structure, including all possible isolated enantiomers corresponding to the formula, all possible mixtures of enantiomers corresponding to the formula, all possible mixtures of diastereomers corresponding to the formula, all possible mixtures of epimers corresponding to the formula and all possible racemic mixtures corresponding to the formula. In addition to this, the above formulae (and all formulae herein) are intended to represent all tautomeric forms equivalent to the corresponding formula.
There is further disclosed a PARP7 inhibitor compound, which compound comprises the following formula:
wherein each X1 may be the same or different and is independently selected from C, N, O and S; each Y may be the same or different and is independently selected from C and N; Z1 and Z2 may be the same or different; Z1 is independently selected from C and N; Z2 is independently selected from C, N, O and S; each X1 may independently be unsubstituted, or may independently be substituted with H or a substituted or unsubstituted organic group; each Y may independently be unsubstituted, or may independently be substituted with H or a substituted or unsubstituted organic group; Z1 may independently be further substituted with H or a substituted or unsubstituted organic group; Z2 may independently be further substituted with H or a substituted or unsubstituted organic group; m may be 1, 2, 3 or 4; n may be 1, 2, 3, or 4; the bonds between all of the atoms in ring A may independently be single bonds or double bonds provided that when X1 is 0 or S the bonds to that X1 are single bonds; the bonds between all of the atoms in ring B may independently be single bonds or double bonds provided that when X1 or Z2 is O or S the bonds to that X1 or Z2 are single bonds; and wherein R1 may be attached to Z1 by a single bond or a double bond and is a substituent of formula:
wherein each Q may be the same or different and is independently selected from C, N, O and S; each Q may independently be attached to another Q, or to Z3, by a single bond or a double bond; each Q may independently be unsubstituted, or may independently be substituted by H or a substituted or unsubstituted organic group; two or more Q atoms may form a ring together with their substituents; p is a number from 2 to 8; each Z3 may be the same or different and is independently selected from C and N; each Z3 may independently be further substituted with H or a substituted or unsubstituted organic group; each X2 may be the same or different and is independently selected from C, N, O and S, preferably from C and N; r is a number from 1 to 5; s is independently a number from 1 to 5; R4 is a substituted or unsubstituted organic group comprising a substituted or unsubstituted carbocyclic or heterocyclic ring; each bond in the ring comprised of Z3 and X2 atoms may independently be a double bond or a single bond, provided that when X2 is O or S the bonds to that X2 are single bonds; each R5 may be present or absent depending on the number of bonds to, and the valence of, the X2 atom attached to that R5; and wherein each R5 is independently selected from H or a substituted or unsubstituted organic group;
and wherein R2 may be present or absent, and when present may be attached to Z2 by a single bond or a double bond and is selected from H or a substituted or unsubstituted organic group.
Typically, when Z2 is C, R2 is present and is selected from a substituted or unsubstituted organic group.
There is further disclosed a PARP7 inhibitor compound, which compound comprises the following formula:
wherein each X1 may be the same or different and is independently selected from C, N, O and S; each Y may be the same or different and is independently selected from C and N; Z1 and Z2 may be the same or different; Z1 is independently selected from C and N; Z2 is independently selected from C, N, O and S; each X1 may independently be unsubstituted, or may independently be substituted with H or a substituted or unsubstituted organic group; each Y may independently be unsubstituted, or may independently be substituted with H or a substituted or unsubstituted organic group; Z1 may independently be further substituted with H or a substituted or unsubstituted organic group; Z2 may independently be further substituted with H or a substituted or unsubstituted organic group; m may be 1, 2, or 3; n may be 1, 2, or 3; the bonds between all of the atoms in ring A may independently be single bonds or double bonds provided that when X1 is O or S the bonds to that X1 are single bonds; the bonds between all of the atoms in ring B may independently be single bonds or double bonds provided that when X1 or Z2 is O or S the bonds to that X1 or Z2 are single bonds;
and wherein R1 is as defined herein.
The term “comprises” as used throughout the description and claims herein means “includes or consists of”. The term denotes the inclusion of at least the features following the term and does not exclude the inclusion of other features which have not been explicitly mentioned. The term may also denote an entity which consists only of the features following the term.
The invention will now be described in more detail, by way of example only, with reference to the following specific embodiments and the accompanying drawings, in which:
The compounds of the invention may be synthesised using readily available starting materials and known reactions.
Exemplary syntheses of various compounds are shown below:
To a stirred solution of 2,2,6,6-tetramethylpiperidine (1.9 mL, 11.5 mmol) in anhydrous THE (10 mL) was added nBuLi (2.4 M in hexanes, 4.8 mL, 11.5 mmol) dropwise at −20° C. under N2. After cooling to −50° C., 3-bromobenzoic acid 1001 (1 g, 5 mmol) in THE (10 mL) was added dropwise and the reaction mixture was stirred for 2 h at −50° C. Then N, N-dimethylformamide (1.9 mL, 25.0 mmol) was added dropwise at this temperature. The resulting reaction mixture was then warmed to room temperature slowly and stirred for additional 14 h. The reaction mixture was poured into ice-water (20 mL) carefully and stirred for 10 min. Then the mixture was washed with EtOAc (20 mL) twice. The obtained aqueous layer was acidified with 1 M HCl aqueous at 0° C. and extracted with EtOAc (30 mL×3). The organic layers were combined, dried over Na2SO4, filtered and concentrated in vacuo. The residue was purified by flash chromatography (eluting with petroleum ether/EtOAc=80:20 to 0:100). After concentration, the resulting solid was triturated with PE (x mL) to afford 4-bromo-3-hydroxyisobenzofuran-1(3H)-one 1002 (0.2 g, 95% purity, 16% yield) as a light yellow solid.
LCMS (ESI) calcd for C8H5BrO3 [M−H]− m/z 226.93, found 227.
To a solution of 4-bromo-3-hydroxyisobenzofuran-1(3H)-one 1002 (100 mg, 0.44 mmol) in ethanol (5 mL) was added hydrazine hydrate (80%, 136.3 mg, 2.18 mmol) in one portion. The reaction mixture was stirred at 80° C. for 2 h. The reaction mixture was cooled to rt and then filtered. The filter cake was rinsed with EtOH (5 mL×2) and then dried in vacuo to give 5-bromophthalazin-1(2H)-one 1003 (90 mg, 95% purity, 87% yield) as white needles.
LCMS (ESI) calcd for C8H5BrN2O [M+H]+ m/z 224.97, found 225.
In a three-neck flask, equipped with stirring bar, condenser and a rubber septum, thoroughly purged with N2, were introduced 5-bromophthalazin-1(2H)-one 1003 (2 g, 8.9 mmol), Pd(dppf)Cl2 (0.65 g, 0.8 mmol), B2Pin2 (5.65 g, 22.2 mmol) and potassium acetate (2.62 g, 26.7 mmol). The flask was purged with N2 once more before adding DMF (100 mL) via syringe. The resulting mixture was stirred at 100° C. for 1 h. After cooling to room temperature, the reaction mixture was poured into cold water and then extracted with EtOAc (200 mL×4). The combined organic layer was concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with petroleum ether/EtOAc=20:80 to 0:100) to afford 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phthalazin-1(2H)-one 1004 (0.5 g, 95% purity, 19% yield) as a white solid.
LCMS (ESI) calcd for C14H17BN2O3[M+H]+ m/z 272.14, found 273.
To a stirred solution of 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phthalazin-1(2H)-one 1004 (500 mg, 1.84 mmol) and methyl 3-(bromomethyl)benzoate (463 mg, 2.02 mmol) in 1,4-dioxane/H2O (50 mL, 4:1) was added K3PO4 (1170 mg, 5.51 mmol) at room temperature. Nitrogen was purged into the reaction mixture for 5 min before adding Pd(pddf)Cl2·DCM (150 mg, 0.18 mmol, the mixture was subsequently purged with N2 for additional 5 min. The reaction mixture was stirred at 80° C. for 1.5 h. The reaction mixture was cooled to rt, diluted with water (30 mL) and extracted with EtOAc (50 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated in vacuo. The residue was purified by flash chromatography (eluting with PE/EtOAc=60:40˜0:100) to give methyl 3-((1-oxo-1,2-dihydrophthalazin-5-yl)methyl)benzoate 1005 (500 mg, 85% purity, 78% yield) as a brown solid.
LCMS (ESI) calcd for C17H14N2O3 [M+H]+ m/z 295.11, found 295.
To a solution of methyl 3-((1-oxo-1,2-dihydrophthalazin-5-yl)methyl)benzoate 1005 (500 mg, 1.70 mmol) in THF/H2O (40 mL, 3:1) was added LiOH (203 mg, 8.49 mmol). The mixture was stirred at 50° C. for 1 h. THE was removed under reduced pressure and the aqueous phase was acidified with 1 M HCl aq. to pH=4˜5. The resulting solid was collected by filtration and dried in vacuo to obtain 3-((1-oxo-1,2-dihydrophthalazin-5-yl)methyl)benzoic acid 1006 (350 mg, 85% purity, 62% yield) as a gray solid.
LCMS (ESI) calcd for C16H12N2O3 [M+H]+ m/z 281.09, found 281.
To a solution of 3-((1-oxo-1,2-dihydrophthalazin-5-yl)methyl)benzoic acid 1006 (150 mg, 0.54 mmol) in DCM (15 mL) was added HATU (305 mg, 0.80 mmol), DIPEA (208 mg, 1.61 mmol) and 6-(piperazin-1-yl)pyridine-3-carbonitrile hydrochloride (132 mg, 0.59 mmol) at room temperature successively. The mixture was kept stirring at room temperature for 1 h. The resulting mixture was diluted with water and extracted with DCM (30 mL×3). The combined organic layer was dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by pre-HPLC (columns: Shim-pack GIST 5 um C18 20×250 mm, mobile phase: ACN-H2O (0.1% FA), gradient: 35-75) to give 6-(4-(3-((1-oxo-1,2-dihydrophthalazin-5-yl)methyl)benzoyl)piperazin-1-yl)nicotinonitrile 1 (35.7 mg, 99% purity, 14% yield) as a white solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.72 (s, 1H), 8.56 (s, 1H), 8.51 (d, J=2.4 Hz, 1H), 8.15 (dd, J=7.0, 1.8 Hz, 1H), 7.90 (dd, J=9.0, 2.2 Hz, 1H), 7.85-7.77 (m, 2H), 7.42-7.25 (m, 4H), 6.92 (d, J=9.2 Hz, 1H), 4.49 (s, 2H), 3.83-3.53 (m, 6H), 3.38 (s, 2H).
LCMS (ESI) calcd for C26H22N6O2 [M+H]+ m/z 451.19, found 451.
To a stirred solution of NaH (60% wt, 1.56 g, 39.1 mmol) in THE (100 mL) at 0° C. was added ethyl 2-methyl-1H-pyrrole-3-carboxylate 1101 (5 g, 32.6 mmol) in portions. After stirring 15 min at 0° C., ethyl 2-bromoacetate (6 g, 35.9 mmol) was added dropwise and the reaction was warmed to rt and stirred for 16 h. The reaction was quenched with saturated aqueous NH4Cl and extracted with EtOAc (50 mL×4). The combined organic layers were washed with brine (30 mL), dried over Na2SO4 and concentrated in vacuo. The residue was purified by flash chromatography (eluting with petroleum ether/EtOAc=90 to 60:40) to afford ethyl 1-(2-ethoxy-2-oxoethyl)-2-methyl-1H-pyrrole-3-carboxylate 1102 (7 g, 90% purity, 80% yield) as an off-white solid.
LCMS (ESI) calcd for C12H17NO4 [M+H]+ m/z 240.12, found 240.
Ethyl 1-(2-ethoxy-2-oxoethyl)-2-methyl-1H-pyrrole-3-carboxylate 1102 (7 g, 29.3 mmol) was dissolved in THE (120 mL) under stirring, followed by addition a solution of AcOH (140 mL) and H2O (120 mL). The mixture was homogeneously stirred at 0° C. and cerium(IV) ammonium nitrate (64 g, 117.2 mol) was added in one portion. After stirring at rt for 1 h, the reaction mixture was poured into ice-water (300 mL) and stirred for another 30 min. The resulting solution was extracted with EtOAc (200 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with petroleum ether/EtOAc=100:0 to 80:20) to obtain the title compound ethyl 1-(2-ethoxy-2-oxoethyl)-2-formyl-1H-pyrrole-3-carboxylate 1103 (3 g, 95% purity, 38% yield) as a yellow solid.
LCMS (ESI) calcd for C12H15NO5 [M+H]+ m/z 254.10, found 254.
To a solution of ethyl 1-(2-ethoxy-2-oxoethyl)-2-formyl-1H-pyrrole-3-carboxylate 1103 (3 g, 11.8 mmol) in AcOH (30 mL) was added H2NNH2·H2O (80% wt, 1.11 g, 17.7 mmol) in one portion. The reaction mixture was heated with stirring at 100° C. for 1 h. Most of the solvent was removed by evaporation (55° C.) under reduced pressure. The residue was cooled in an ice-water bath. The precipitate formed was collected and then rinsed with water (10 mL×2). The solid was dried (55° C.) in vacuo to give ethyl 2-(4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]-pyridazin-1-yl)-acetate 1104 (1.9 g, 95% purity, 69% yield) as a yellow solid.
LCMS (ESI) calcd for C10H11N3O3[M+H]+ m/z 222.09, found 222.
To a solution of ethyl 2-(4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]-pyridazin-1-yl)-acetate 1104 (1.45 g, 6.6 mmol) and DIPEA (4.26 g, 33.0 mmol) in DMF (20 mL) at rt, SEMCl (5.5 g, 33.0 mmol) was added. After addition, the reaction solution was heated at 80° C. for 1 h. The resulting reaction solution was poured into cold water and then extracted with EtOAc (100 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=70:30 to 40:60) to give ethyl 2-(4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1105 (2 g, 95% purity, 81% yield) as an off-white solid.
LCMS (ESI) calcd for C16H25N3O4Si [M+H]+ m/z 352.17, found 352.
To a suspension of LiAlH4 (0.31 g, 8.1 mmol) in THE (35 mL), ethyl 2-(4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1105 (1.9 g, 5.4 mmol) in THF (15 mL) was added dropwise under N2 atmosphere, during which the temperature was kept at 0-5° C. The reaction mixture was stirred at this temperature for a further 1 h. After the dropwise addition of water (0.3 mL) and 13% aq. NaOH (0.6 mL) successively, the mixture was stirred for an additional 30 min. The resulting mixture was filtered through diatomaceous earth and the filter cake was thoroughly washed with DCM. The filtrate was concentrated to dryness under reduced pressure. The residue was purified by flash chromatography (eluting with DCM/MeOH=100:0 to 90:10) to obtain 1-(2-hydroxyethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1106 (1 g, 85% purity, 59% yield) as a yellow solid.
LCMS (ESI) calcd for C14H23N3O3Si [M+H]+ m/z 310.16, found 310.
To a solution of 1-(2-hydroxyethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1106 (500 mg, 1.61 mmol, 1 eq.) in THE (50 mL), Na (74 mg, 3.22 mmol, 2 eq.) cut in pieces was added at rt. After stirring for 30 min, tert-butyl acrylate (619 mg, 4.83 mmol, 3 eq.) was added in one portion. The reaction mixture was stirred at rt for an additional 5 h. The reaction solution was sucked out (the rest of the Na was suspended in fresh THE and quenched with EtOH and then H2O) and poured into cold water, and then extracted with EtOAc (30 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with petroleum ether/EtOAc=60:40 to 30:70) to give tert-butyl 3-(2-(4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)ethoxy)propanoate 1107 (530 mg, 95% purity, 71% yield) as a colorless oil.
LCMS (ESI) calcd for C21H35N3O5Si [M+H]+ m/z 438.24, found 438
A solution of tert-butyl 3-(2-(4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)ethoxy)propanoate 1107 (530 mg, 1.21 mmol) in HCl-Dioxane (4 M, 30 mL) was stirred at rt for 16 h under N2 atmosphere. The resulting reaction mixture was evaporated under reduced pressure to afford 3-(2-(4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)ethoxy)propanoic acid 1108 (300 mg, 85% purity, 84% yield) as a yellow solid.
LCMS (ESI) calcd for C11H13N3O4 [M+H]+ m/z 252.10, found 252.
To a solution of 3-(2-(4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)ethoxy)propanoic acid 1108 (150 mg, 0.60 mmol) in MeCN (10 mL) was added 2-methylimidazole (123 mg, 1.49 mmol), TCFH (201 mg, 0.71 mmol) and 2-(piperazin-1-yl)-5-(trifluoromethyl)pyrimidine hydrochloride (209 mg, 0.78 mmol) at room temperature successively. The mixture was kept stirring at room temperature for 16 h. The resulting mixture was diluted with water (10 mL) and extracted with DCM (30 mL×3). The combined organic layer was dried over Na2SO4 and concentrated in vacuo. The residue was purified by flash chromatography (eluting with DCM/MeOH=100:0 to 90:10) and pre-HPLC (columns: Gemini 5 um C18 150×21.2 mm, mobile phase: ACN-H2O (0.1% FA), gradient: 30-70) to give 1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 10 (30.9 mg, 99% purity, 10% yield) as a white solid. 1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.23 (s, 1H), 8.74 (s, 2H), 8.34 (s, 1H), 7.41 (d, J=2.8 Hz, 1H), 6.61 (d, J=2.8 Hz, 1H), 4.38 (t, J=4.8 Hz, 2H), 3.83-3.75 (m, 4H), 3.72 (t, J=4.8 Hz, 2H), 3.63 (t, J=6.4 Hz, 2H), 3.55-3.46 (m, 4H), 2.55-2.53 (m, 2H).
LCMS (ESI) calcd for C20H22F3N7O3[M+H]+ m/z 466.18, found 466.
To a stirred suspension of NaH (60%, 0.78 g, 19.6 mmol) in THE (60 mL) was added 5-bromophthalazin-1(2H)-one 1003 (2.2 g, 9.8 mmol) in portions under nitrogen at 0° C. and then stirred for additional 10 min. After adding SEM-Cl (2.45 g, 14.7 mmol,), the reaction mixture was warmed to rt and stir for another 16 h. The resulting reaction mixture was poured into cold water (30 mL) and then extracted with EtOAc (50 mL×3). The combined organic layer was washed with brine, dried over anhydrous sodium sulfate and concentrated under reduced pressure. Purification by flash chromatography (eluting with petroleum ether/EtOAc=70:30 to 40:60) provided 5-bromo-2-((2-(trimethylsilyl)ethoxy)methyl)phthalazin-1(2H)-one 1201 (1.3 g, 95% purity, 35% yield) as a light yellow oil.
LCMS (ESI) calcd for C14H19BrN2O2Si [M+H]+ m/z 355.05, found 355, 357
To a solution of 5-bromo-2-((2 (trimethylsilyl)ethoxy)methyl)phthalazin-1(2H)-one 1201 (500 mg, 1.41 mmol) in dioxane/H2O (10 mL, 1:1) was added Pd2(dba)3 (64 mg, 0.07 mmol), t-BuXPHOS (60 mg, 0.14 mmol) and KOH (240 mg, 4.23 mmol). The reaction mixture was stirred at 120° C. for 3 h. The reaction mixture was concentrated in vacuo. The residue was purified by silica gel column chromatography (eluting with petroleum ether/EtOAc=100:0 to 90:10) to afford 5-hydroxy-2-((2 (trimethylsilyl)ethoxy) methyl)phthalazin-1(2H)-one 1202 (321 mg, 90% purity, 78% yield) as a yellow solid.
LCMS (ESI) calcd for C14H20N2O3Si [M+H]+ m/z 293.13, found 293.
To a solution of 5-hydroxy-2-((2-(trimethylsilyl)ethoxy)methyl)phthalazin-1(2H)-one 1202 (200 mg, 0.685 mmol) in acetone (5 mL) were added K2CO3 (171 mg, 2.058 mmol) and methyl 2-bromopropanoate (235 mg, 1.029 mmol). The reaction mixture was stirred at 80° C. for 3 h. The reaction solution was concentrated under reduced pressure. The residue was purified by silica gel column (eluting with petroleum ether/EtOAc=95:5 to 75:5) to obtain methyl 2-((1-oxo-2-((2-(trimethylsilyl)ethoxy)methyl)-1,2-dihydrophthalazin-5-yl)oxy)propanoate 1203 (246 mg, 90% purity, 95% yield) as yellow solid.
LCMS (ESI) calcd for C18H26N2O5Si [M+H]+ m/z 379.17, found 379.
To a solution of methyl 2-((1-oxo-2-((2-(trimethylsilyl)ethoxy)methyl)-1,2-dihydrophthalazin-5-yl)oxy)propanoate 1203 (500 mg, 1.322 mmol) in EtOH (5 mL) was added LiCl (224 mg, 5.291 mmol). The reaction mixture was stirred at rt for 1 h. Then NaBH4 (200 mg, 5.291 mmol) was added in portions. Then the reaction mixture was stirred at rt overnight. The resulting mixture was quenched with water and extracted with DCM (10 mL×3). The organic phase was concentrated under reduced pressure to obtain 5-((1-hydroxypropan-2-yl)oxy)-2-((2-(trimethylsilyl)ethoxy)methyl)phthalazin-1(2H)-one 1204 (460 mg, 90% purity, 99% yield) as a white solid.
LCMS (ESI) calcd for C17H26N2O4Si [M+H]+ m/z 351.17, found 351.
To a solution of 5-((1-hydroxypropan-2-yl)oxy)-2-((2-(trimethylsilyl)ethoxy)methyl)phthalazin-1(2H)-one 1204 (200 mg, 0.571 mmol) in THE (2 mL) was added NaH (60 wt %, 46 mg, 1.143 mmol) at 0° C. The reaction mixture was stirred at rt for 0.5 h, then to the mixture 2-chloro-1-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)ethan-1-one (211 mg, 0.685 mmol) was added in one portion at rt and stirred at rt overnight. The reaction solution was concentrated under reduced pressure. The residue was purified by silica gel column (eluting with DCM/MeOH=95:5) to obtain 5-((1-(2-oxo-2-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)ethoxy)propan-2-yl)oxy)-2-((2-(trimethylsilyl)ethoxy)methyl)phthalazin-1(2H)-one 1205 (170 mg, 90% purity, 48% yield) as white solid.
LCMS (ESI) calcd for C28H37F3N6O5Si [M+H]+ m/z 623.25, found 623.
5-((1-(2-oxo-2-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)ethoxy)propan-2-yl)oxy)-2-((2-(trimethylsilyl)ethoxy)methyl)phthalazin-1(2H)-one 1205 (150 mg, 0.241 mmol) was dissolved in HCl-dioxane (4 M, 4 mL). The reaction mixture was stirred at rt overnight under N2. The solvent was removed and the residue was purified by prep-HPLC (columns: Gemini 5 um C18 150×21.2 mm, mobile phase: ACN-H2O (0.1% FA), gradient: 25-65) to give 5-((1-(2-oxo-2-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)ethoxy)propan-2-yl)oxy)phthalazin-1(2H)-one 33 racemate (84 mg, 97% purity, 71% yield) as a white solid.
LCMS (ESI) calcd for C22H23F3N6O4 [M+H]+ m/z 493.18, found 493.
Compound 33 (racemate) was separated by SFC (Column: Daicel CHIRALPAK OJ-H 250 mm×20 mm I.D., 5 mm; Mobile phase: CO2/MeOH[0.2% (NH3)]=70/30) and concentrated under reduced pressure to afford the first fraction as Compound 33 enantiomer 1 (26.7 mg, 99% purity, ee %: 100, white solid) and the second fraction as Compound 33 enantiomer 2 (25 mg, 99% purity, ee %: 100, white solid)
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.67 (s, 1H), 8.71 (s, 2H), 8.44 (s, 1H), 7.82-7.66 (m, 2H), 7.56 (d, J=6.9 Hz, 1H), 4.90 (dd, J=10.8, 5.6 Hz, 1H), 4.39-4.20 (m, 2H), 3.90-3.64 (m, 6H), 3.48 (d, J=18.9 Hz, 4H), 1.33 (d, J=6.2 Hz, 3H).
LCMS (ESI) calcd for C22H23F3N6O4 [M+H]+ m/z 493.18, found 493.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.67 (s, 1H), 8.71 (s, 2H), 8.44 (s, 1H), 7.79-7.64 (m, 2H), 7.56 (dd, J=7.0, 2.0 Hz, 1H), 4.90 (dd, J=10.8, 5.7 Hz, 1H), 4.39-4.16 (m, 2H), 3.99-3.63 (m, 6H), 3.48 (d, J=19.2 Hz, 4H), 1.33 (d, J=6.2 Hz, 3H).
LCMS (ESI) calcd for C22H3F3N6O4 [M+H]+ m/z 493.18, found 493.
To a solution of ethyl 4,4-diethoxy-3-oxobutanoate 1301 (4 g, 0.0183 mol) in xylene (40 mL), DMF-DMA (4.36 g, 0.0366 mol) was added. The mixture was stirred at 140° C. for 2 h. After cooling to room temperature, the reaction mixture was poured into cold water and then extracted with EtOAc (50 mL×4). The combined organic layer was washed three times with brine solution, dried over Na2SO4 and concentrated under reduced pressure to give ethyl (Z)-2-((dimethylamino)methylene)-4,4-diethoxy-3-oxobutanoate 1302 (4 g, 60% purity, 48% yield) as a brown liquid which was used directly in the next step.
LCMS (ESI) calcd for C13H23NO5 [M+H]+ m/z 274.16, found 274.
To a stirred solution of ethyl (Z)-2-((dimethylamino)methylene)-4,4-diethoxy-3-oxobutanoate 1302 (4 g, 0.0146 mol) and ethyl aminoglycinate hydrochloride 1303 (2.23 g, 0.0146 mmol) in DMF (40 mL) was added DIPEA (5.66 g, 0.0438 mmol) at room temperature. The reaction mixture was stirred at rt for 2 h. After the reaction completed, the reaction mixture was poured into cold water and then extracted with EtOAc (50 mL×4). The combined organic layer was washed three times with brine solution, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 50:50) to afford ethyl 5-(diethoxymethyl)-1-(2-ethoxy-2-oxoethyl)-1H-pyrazole-4-carboxylate 1304 (3.2 g, 90% purity, 60% yield) as a yellow liquid.
LCMS (ESI) calcd for C15H24N2O6 [M+H]+ m/z 329.17, found 329.
To a solution of ethyl 5-(diethoxymethyl)-1-(2-ethoxy-2-oxoethyl)-1H-pyrazole-4-carboxylate 1304 (3.2 g, 0.0097 mol) in AcOH (50 mL) were added con. HCl (0.18 g, 0.0048 mmol) and H2NNH2·H2O (80% wt, 0.61 g, 0.0097 mmol). The mixture was stirred at 100° C. for 2 h. AcOH was removed under reduced pressure. The residue was diluted with water and extracted with DCM (30 mL×3). The combined organic layer was dried over Na2SO4 and concentrated under reduced pressure. The crude product was purified by flash chromatography (eluting with DCM/MeOH=90:10 to 80:20) to give ethyl 2-(4-oxo-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)acetate 1305 (0.7 g, 90% purity, 28% yield) as a white solid.
LCMS (ESI) calcd for C9H10N4O3[M+H]+ m/z 223.08, found 223.
To a solution of ethyl 2-(4-oxo-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)acetate 1305 (730 mg, 3.285 mmol) in DMF (20 mL) were added SEMCl (821 mg, 4.928 mmol) and DIPEA (1273.78 mg, 9.856 mol) at rt. Then the reaction mixture was stirred 80° C. for 2 h. After cooling to room temperature, the reaction mixture was poured into cold water and then extracted with EtOAc (50 mL×4). The combined organic layer was washed three times with brine solution, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 50:50) to afford ethyl 2-(4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrazolo [3,4-d]pyridazin-1-yl)acetate 1306 (700 mg, 95% purity, 57% yield) as a white solid.
LCMS (ESI) calcd for C15H24N4O4Si [M+H]+ m/z 353.16, found 353.
To a stirred solution of ethyl 2-(4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrazolo [3,4-d]pyridazin-1-yl)acetate 1306 (690 mg, 1.952 mmol) in 20 ml of THF was added LiAlH4 (114 mg, 2.928 mmol) in portions at 0° C. The mixture was stirred at 0° C. for 5 min, then the reaction mixture was quenched with H2O (0.1 mL), NaOH (15% wt in water, 0.3 mL) and H2O (0.3 mL) successively. The resulting mixture was filtered through diatomaceous earth and washed with DCM several times. The filtrate was concentrated under reduced pressure to afford 1-(2-hydroxyethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 1307 (600 mg, 90% purity, 88% yield) as a yellow oil.
LCMS (ESI) calcd for C13H22N4O3Si [M+H]+ m/z 311.15, found 311.
To a solution of 1-(2-hydroxyethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 1307 (300 mg, 0.963 mmol) in DCM (15 mL) were added ethyl propiolate 1308 (94 mg, 0.963 mmol) and P(n-Bu)3 (19 mg, 0.0963 mmol) successively at room temperature. The solution was then stirred at rt for 1 h. After reaction completed, the reaction mixture was concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=70:30 to 30:70) to give ethyl (E)-3-(2-(4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy)acrylate 1309 (200 mg, 95% purity, 48% yield) as a yellow oil.
LCMS (ESI) calcd for C18H28N4O5Si [M+Na]+ m/z 431.17, found 431.
To a solution of ethyl (E)-3-(2-(4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy)acrylate 1309 (200 mg, 0.488 mmol) in MeOH (10 mL) was added Pd/C (17 mg) at room temperature. The reaction mixture was stirred at rt for 16 h under H2 atmosphere. The reaction solution was filtered through diatomaceous earth. Then the filtrate was concentrated under reduced pressure to obtain ethyl 3-(2-(4-oxo-5-((2-(trimethylsilyl)ethoxy) methyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy)propanoate 1310 (190 mg, 95% purity, 89% yield) as yellow oil.
LCMS (ESI) calcd for C18H30N4O5Si [M+H]+ m/z 411.20, found 411.
To a solution of ethyl 3-(2-(4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy)propanoate 1310 (190 mg, 0.4617 mmol) in HCl-Dioxane (4 M, 20 mL) was added at rt and the reaction was stirred for additional 16 h. The resulting reaction mixture was evaporated under reduced pressure to afford ethyl 3-(2-(4-oxo-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy) propanoate 1311 (200 mg, 60% purity, 92% yield) as a yellow oil.
LCMS (ESI) calcd for C12H16N4O4 [M+H]+ m/z 281.12, found 281.
To a solution of ethyl 3-(2-(4-oxo-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy)propanoate 1311 (200 mg, 0.7136 mmol) in THF/H2O (20 mL, 3:1) was added LiOH (51 mg, 2.141 mmol). The mixture was stirred at rt for 1 h. THF was removed under reduced pressure and the aqueous phase was acidified with 1 M aq. HCl to pH=4˜5. The residue was purified by C18 columns (mobile phase: ACN-H2O (0.1% FA), gradient: 40-60) to give 3-(2-(4-oxo-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy)propanoic acid 1312 (35 mg, 97% purity, 18% yield) as a white solid.
LCMS (ESI) calcd for C10H12N4O4 [M+H]+ m/z 253.09, found 253.
To a solution of 3-(2-(4-oxo-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy)propanoic acid 1312 (35 mg, 0.139 mmol) in DCM (5 mL) were added 2-(piperazin-1-yl)-5-(trifluoromethyl) pyrimidine hydrochloride Int 3 (48 mg, 0.208 mmol), DIPEA (89 mg, 0.694 mmol), T3P (50% in EtOAc, 132 mg, 0.208 mmol) at room temperature successively. The mixture was kept stirring at room temperature for 1 h. The resulting mixture was diluted with water and extracted with DCM (30 mL×3). The combined organic layer was dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by C18 column (mobile phase: ACN-H2O (0.1% FA), gradient: 40-60) to give 1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl) piperazin-1-yl)propoxy) ethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 50 (10 mg, 97% purity, 14% yield) as white solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.51 (s, 1H), 8.73 (s, 2H), 8.50 (s, 1H), 8.22 (s, 1H), 4.60 (t, J=4.8 Hz, 2H), 3.84-3.71 (m, 6H), 3.61 (t, J=6.4 Hz, 2H), 3.52-3.43 (m, 4H), 2.48-2.46 (m, 2H).
LCMS (ESI) calcd for C19H21F3N8O3[M+H]+ m/z 467.17, found 467.
To the solution of ethyl 2-methyl-1H-pyrrole-3-carboxylate 1401 (5.0 g, 32.64 mmol) in THE (300 mL) was added NBS (5.8 g, 32.64 mmol). The reaction mixture was stirred at −78° C. for 1 h. After LCMS showed that the 1402 formed completely, NaH (6.5 g, 163.20 mmol, 60% wt) was added to the reaction mixture. Ethyl 2-bromoacetate 1403 (6.5 g, 39.17 mmol) was added after the reaction mixture was stirred at 0° C. for 30 min. The reaction solution was stirred at rt for 16 h until 1402 was consumed completely. The reaction mixture was quenched with saturated aqueous NH4Cl (20 mL). The aqueous layer was extracted with EtOAc (200 ml×2). The combined organic layers were concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=85:15 to 70:30) to afford ethyl 5-bromo-1-(2-ethoxy-2-oxoethyl)-2-methyl-1H-pyrrole-3-carboxylate 1404 (9.29 g, 90% purity, 81% yield) as a white solid.
LCMS (ESI) calcd for C12H16BrNO4 [M+H]+ m/z 318.03, found 318/320.
Ethyl 5-bromo-1-(2-ethoxy-2-oxoethyl)-2-methyl-1H-pyrrole-3-carboxylate 1404 (4.0 g, 12.62 mmol) was dissolved in THE (50 mL) under stirring, followed by addition a solution of AcOH (50 mL) and H2O (50 mL). The mixture was homogeneously stirred at 0° C. and ceric ammonium nitrate (CAN) was added (28 g, 50.47 mmol) in one portion. After stirring at rt for 1 h, the reaction mixture was poured into ice-water (200 mL) and stirred for another 30 min. The resulting solution was extracted with EtOAc (100 mL×3). The combined organic layers were washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 80:20) to obtain ethyl 5-bromo-1-(2-ethoxy-2-oxoethyl)-2-formyl-1H-pyrrole-3-carboxylate 1405 (2.3 g, 90% purity, 49% yield) as a yellow solid.
LCMS (ESI) calcd for C12H14BrNO5 [M+H]+ m/z 332.0, found 332/334.
To a solution of ethyl 5-bromo-1-(2-ethoxy-2-oxoethyl)-2-formyl-1H-pyrrole-3-carboxylate 1405 (2.0 g, 6.04 mmol) in AcOH (20 mL) was added H2NNH2·H2O (80% wt, 1.2 g, 30.20 mmol) in one portion. The reaction mixture was heated with stirring at 80° C. for 1 h. The solvent was removed by evaporation under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=40:60 to 20:80) to give ethyl 2-(2-bromo-4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1406 (900 mg, 90% purity, 45% yield) as a yellow solid.
LCMS (ESI) calcd for C10H10BrN3O3[M+H]+ m/z 299.99, found 300/302.
To a solution of ethyl 2-(2-bromo-4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1406 (1.88 g, 6.3 mmol) and DIPEA (4.10 g, 31.5 mmol) in DMF (15 mL) at rt, SEMCl (2.10 g, 12.6 mmol) was added. After completing of addition, the reaction solution was heated at 50° C. for 1 h. The resulting reaction solution was poured into cold water and then extracted with EtOAc (50 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=70:30 to 40:60) to obtained ethyl 2-(2-bromo-4-oxo-5-((2-(trimethylsilyl)ethoxy) methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1407 (2.5 g, 90% purity, 82% yield) as an off-white solid.
LCMS (ESI) calcd for C16H24BrN3O4Si [M+H]+ m/z 430.1, found 430/432.
To a solution of ethyl 2-(2-bromo-4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1407 (1.10 g, 2.5 mmol) in DMF (20 mL) were added CuI (0.95 g, 5.1 mmol), HMPA (2.24 g, 12.5 mmol) and methyl 2,2-difluoro-2-(fluorosulfonyl)acetate 1408 (2.40 g, 12.5 mmol) successively. The reaction mixture was stirred at 100° C. for 48 h. The resulting reaction solution was poured into cold water and then extracted with EtOAc (50 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=70:30 to 40:60) to obtain ethyl 2-(4-oxo-2-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1409 (455 mg, 90% purity, 40% yield) as an off-white solid.
LCMS (ESI) calcd for C17H24F3N3O4Si [M+H]+ m/z 420.1, found 420.
To the solution of ethyl 2-(4-oxo-2-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1409 (450 mg, 1.07 mmol) in THE (10 mL) was added LiAlH4 (81 mg, 2.14 mmol) in portions at 0° C. The reaction mixture was stirred at 0° C. for 0.5 h. The reaction mixture was quenched with water, the aqueous layer was extracted with EtOAc (50 mL×3). The combined organic layers were concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=50:50 to 40:60) to afford 1-(2-hydroxyethyl)-2-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1410 (297 mg, 90% purity, 66% yield) as a white solid.
LCMS (ESI) calcd for C15H22F3N3O3Si [M+H]+ m/z 378.1, found 378.
To the solution of 1-(2-hydroxyethyl)-2-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1410 (270 mg, 0.71 mmol) in DCM (10 mL) were added ethyl propiolate 1411 (70 mg, 0.71 mmol) and P(n-Bu)3 (72 mg, 0.36 mmol) successively. The reaction mixture was stirred at room temperature for 2 h. The reaction mixture was diluted with DCM (20 mL) and water (20 mL). The aqueous layer was extracted with DCM (20 mL×2). The combined organic layers were dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=70:30 to 60:40) to afford ethyl (E)-3-(2-(4-oxo-2-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)ethoxy)acrylate 1412 (302 mg, 90% purity, 83% yield) as a white solid.
LCMS (ESI) calcd for C20H28F3N3O5Si [M+Na]+ m/z 498.2, found 498.
A solution of ethyl (E)-3-(2-(4-oxo-2-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)ethoxy)acrylate 1412 (300 mg, 0.63 mmol) and Pd/C (30 mg, 10% wt) in MeOH (15 mL) was stirred at rt for 1 h under H2 atmosphere. The resulting solution was filtered through diatomaceous earth and the filter cake was washed with DCM (5 mL×4). The filtrate was concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with DCM/MeOH=97:3 to 95:5) to afford ethyl 3-(2-(4-oxo-2-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)ethoxy)propanoate 1413 (238 mg, 90% purity, 71% yield) as an off-white solid.
LCMS (ESI) calcd for C20H30F3N3O5Si [M+H]+ m/z 478.2, found 478.
Dissolved ethyl 3-(2-(4-oxo-2-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)ethoxy) propanoate 1413 (230 mg, 0.48 mmol) in HCl-dioxane (4 M, 15 mL). The reaction mixture was stirred at room temperature for 12 h. The resulting reaction mixture was evaporated under reduced pressure to give ethyl 3-(2-(4-oxo-2-(trifluoromethyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)ethoxy)propanoate 1414 (180 mg, 90% purity, 97% yield) as a colorless oil.
LCMS (ESI) calcd for C14H16F3N3O4[M+H]+ m/z 348.1, found 348.
To a solution of ethyl 3-(2-(4-oxo-2-(trifluoromethyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)ethoxy)propanoate 1414 (200 mg, 0.57 mmol) in THF/H2O (15 mL, 1:1) was added LiOH (72 mg, 1.72 mmol). The mixture was stirred at room temperature for 2 h. THE was removed under reduced pressure and the aqueous phase was acidified with 1 M HCl aq. to pH=4˜5. The resulting solid was collected by filtration and dried in vacuo to obtain 3-(2-(4-oxo-2-(trifluoromethyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazine-1-yl)ethoxy)propanoic acid 1415 (82 mg, 90% purity, 40% yield) as a white solid.
LCMS (ESI) calcd for C12H12F3N3O4 [M+H]+ m/z 320.0, found 320.
To a solution 3-(2-(4-oxo-2-(trifluoromethyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazine-1-yl)ethoxy)propanoic acid 1415 (40 mg, 0.12 mmol), 2-(piperazin-1-yl)-5-(trifluoromethyl) pyrimidine hydrochloride 1416 (35 mg, 0.15 mmol) in DCM (5 mL) were added DIPEA (658 mg, 0.50 mmol), T3P (50% wt in EtOAc, 160 mg, 0.25 mmol) at rt successively. The reaction mixture was stirred at rt for 1 h. The reaction solution was quenched with water (20 mL) and extracted with DCM (20 mL×3). The organic phase was concentrated and purified by prep-HPLC (columns: Gemini 5 um C18 150×21.2 mm, mobile phase: ACN-H2O (0.1% FA), gradient: 30-95) to obtain 1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-2-(trifluoromethyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 60 (23.4 mg, 100% purity, 35% yield) as a white solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.54 (s, 1H), 8.74 (d, J=0.8 Hz, 2H), 8.40 (s, 1H), 7.27 (s, 1H), 4.49 (t, J=5.0 Hz, 2H), 3.84-3.75 (m, 4H), 3.72 (t, J=5.0 Hz, 2H), 3.61 (t, J=6.4 Hz, 2H), 3.52-3.43 (m, 4H), 2.49-2.44 (m, 2H).
LCMS (ESI) calcd for C21H21F6N7O3 [M+H]+ m/z 534.1, found 534.
To a solution of 5-bromo-2-methylnicotinic acid 1501 (20 g, 92.4 mmol) in MeOH (300 mL) was added SOCl2 (66 mL, 924 mmol) at 0° C. The resulting mixture was stirred at 80° C. for 16 h. After cooling to room temperature, the mixture was concentrated in vacuo. Water (100 mL) was added, and the mixture was extracted EtOAc (3×150 mL). The combined organic layers were dried (Na2SO4), concentrated in vacuo to obtain methyl 5-bromo-2-methylnicotinate 1502 (17.2 g, 90% purity, 73% yield) as colorless oil.
LCMS (ESI) calcd for C8H8BrNO2 [M+H]+ m/z 229.98, found 230.
To a solution of methyl 5-bromo-2-methylnicotinate 1502 (15 g, 65.1 mmol) in CCl4 (350 mL were added NBS (46.4 g, 260.4 mmol) and AIBN (2.1 g, 13.0 mmol) at room temperature. The reaction mixture was stirred at 85° C. for 30 h. After cooling to room temperature, water (400 mL) was added and the mixture was extracted EtOAc (3×350 mL). The combined organic layers were dried (Na2SO4), concentrated in vacuo, and purified by flash chromatography (silica gel, eluting with PE/EtOAc=100:0 to 10:90) to obtain methyl 5-bromo-2-(dibromomethyl)nicotinate 1503 (12 g, 85% purity, 41% yield) as white solid.
LCMS (ESI) calcd for C8H6Br3NO2 [M+H]+ m/z 385.80, found 386.
To a solution of methyl 5-bromo-2-(dibromomethyl)nicotinate 1503 (10 g, 25.8 mmol) in AcOH (150 mL) was added NH2NH2·H2O (6.46 g, 129 mmol) at room temperature. The resulting mixture was stirred at 100° C. for 10 h. After cooling to room temperature, the mixture was concentrated in vacuo. The residue was purified by flash chromatography (silica gel, eluting with PE/EtOAc=100:0 to 20:80) to obtain 3-bromopyrido[2,3-d]pyridazin-5(6H)-one 1504 (5 g, 80% purity, 69% yield) as white solid.
LCMS (ESI) calcd for C7H4BrN3O [M+H]+ m/z 225.96, found 226.
To a solution of 3-bromopyrido[2,3-d]pyridazin-5(6H)-one 1504 (4.8 g, 21.2 mmol) in Dioxane-H2O (60 mL, v/v=3:1) were added K3PO4 (27 g, 127.2 mmol), methylboronic acid (5.08 g, 84.8 mmol) and Pd(dppf)Cl2 (1.56 g, 2.12 mmol) at room temperature. The resulting mixture was degassed 5 min, the mixture was stirred at 100° C. for 18 h. After cooling to room temperature, the mixture was concentrated in vacuo. The residue purified by flash chromatography (silica gel, eluting with PE/EtOAc=100:0 to 0:100) to obtain 3-methylpyrido[2,3-d]pyridazin-5(6H)-one 1505 (2.4 g, 85% purity, 59% yield) as white solid.
LCMS (ESI) calcd for C8H7N3O [M+H]+ m/z 162.07, found 162.
To a solution of 3-methylpyrido[2,3-d]pyridazin-5(6H)-one 1505 (1.2 g, 7.4 mmol) in TFA (100 mL) was added PtO2 (170 mg, 0.74 mmol) at room temperature. The resulting mixture was stirred at room temperature for 18 h under H2 atmosphere. After cooling to room temperature, the mixture was concentrated in vacuo to obtain crude 3-methyl-2,3,4,6-tetrahydropyrido[2,3-d]pyridazin-5(1H)-one as TFA salt 1506 (1.2 g, 80% purity, 67% yield) as white solid.
LCMS (ESI) calcd for C8H11N3O [M+H]+ m/z 166.10, found 166.
To a solution of 3-methyl-2,3,4,6-tetrahydropyrido[2,3-d]pyridazin-5(1H)-one as TFA salt (1506) (2.1 g, 0.0075 mol) in DMSO (80 mL) were added PMBCl (2.35 g, 0.015 mol) and Cs2CO3 (9.77 g, 0.03 mol). The reaction mixture was stirred at 50° C. for 18 h. The reaction solution was quenched with water and extracted with EtOAc (3×100 mL). The organic phase was concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=90:10 to 80:20) to obtain 6-(4-methoxybenzyl)-3-methyl-2,3,4,6-tetrahydropyrido[2,3-d]pyridazin-5(1H)-one 1507 (0.5 g, 95% purity, 22% yield) as white solid.
LCMS (ESI) calcd for C16H19N3O2 [M+H]+ m/z 286.15 found 286.
To a solution of 6-(4-methoxybenzyl)-3-methyl-2,3,4,6-tetrahydropyrido[2,3-d]pyridazin-5(1H)-one 1507 (500 mg, 1.75 mmol) in DMF (40 mL) at 0° C. was added t-BuOK (590 mg, 5.26 mmol) in DMF (10 mL). The reaction mixture was stirred at 0° C. for 10 min. Then added ethyl 2-bromoacetate (878 mg, 5.25 mmol) in DMF (25 mL) at 0° C. The reaction mixture was stirred at 0° C. for 15 min, and then warmed to rt and stirred at rt for 1 h. The reaction solution was quenched with water and extracted with EtOAc (3×50 mL). The organic phase was concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=90:10 to 0:100) to obtain ethyl 2-(6-(4-methoxybenzyl)-3-methyl-5-oxo-3,4,5,6-tetrahydropyrido[2,3-d]pyridazin-1(2H)-yl)acetate 1508 (560 mg, 90% purity, 77% yield) as yellow oil.
LCMS (ESI) calcd for C20H25N3O4 [M+H]+ m/z 372.18 found 372.
To a solution of ethyl 2-(6-(4-methoxybenzyl)-3-methyl-5-oxo-3,4,5,6-tetrahydropyrido[2,3-d]pyridazin-1(2H)-yl)acetate 1508 (500 mg, 1.34 mmol) in THE (30 mL) at 0° C. was added LiAlH4 (102 mg, 2.69 mmol). The reaction mixture was stirred at 0° C. for 15 min. The reaction solution was quenched with water and filtered. The filtered liquid was extracted with EtOAc (3×20 mL). The organic phase was concentrated under reduced pressure. The residue was purified by silica gel column (eluting with DCM/MeOH=100:0 to 95:5) to obtain 1-(2-hydroxyethyl)-6-(4-methoxybenzyl)-3-methyl-2,3,4,6-tetrahydropyrido[2,3-d]pyridazin-5(1H)-one 1509 (250 mg, 95% purity, 53% yield) as white solid.
LCMS (ESI) calcd for C18H23N3O3 [M+H]+ m/z 330.17, found 330.
To a solution of 1-(2-hydroxyethyl)-6-(4-methoxybenzyl)-3-methyl-2,3,4,6-tetrahydropyrido[2,3-d]pyridazin-5(1H)-onee 1509 (140 mg, 0.42 mmol) in DCM (10 mL) at rt were added 1-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-2-yn-1-one (133 mg, 0.47 mmol) and P(n-Bu)3 (43 mg, 0.21 mmol). The reaction mixture was stirred at rt for 3 h. The reaction solution was concentrated under reduced pressure. The residue was purified by prep-TLC (eluting with DCM/MeOH=95:5) to obtain (E)-6-(4-methoxybenzyl)-3-methyl-1-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-2,3,4,6-tetrahydropyrido[2,3-d]pyridazin-5(1H)-one 1510 (310 mg, 60% purity, 71% yield) as white solid.
LCMS (ESI) calcd for C30H34F3N7O4[M+H]+ m/z 614.26, found 614.35.
To a solution of (E)-6-(4-methoxybenzyl)-3-methyl-1-(2-((3-oxo-3-(4-(5-(trifluoromethyl) pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-2,3,4,6-tetrahydropyrido[2,3-d]pyridazin-5(1H)-one 1510 (310 mg, 0.50 mmol) in MeOH (10 mL) at rt was added Pd/C (32 mg, 0.30 mmol). The reaction mixture was stirred at rt for 18 h. The reaction solution was filtered and concentrated under reduced pressure to obtain 6-(4-methoxybenzyl)-3-methyl-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-2,3,4,6-tetrahydropyrido[2,3-d]pyridazin-5(1H)-one 1511 (200 mg, 80% purity, 50% yield) as yellow oil.
LCMS (ESI) calcd for C30H36F3N7O4[M+H]+m/z 616.28, found 616.
To a solution of 6-(4-methoxybenzyl)-3-methyl-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl) pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-2,3,4,6-tetrahydropyrido[2,3-d]pyridazin-5(1i)-one 1511 (200 mg, 0.32 mmol) in TFA (20 mL) was stirred at 100° C. overnight. The solvent was removed under reduced pressure. Then the reaction was quenched with water and adjusted pH to 7˜8 with 1 M NaOH aqueous. The aqueous phase was purified by C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 50-95) to give 3-methyl-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl) pyrimidin-2-yl) piperazin-1-yl) propoxy) ethyl)-2,3,4,6-tetrahydropyrido[2,3-d]pyridazin-5(1H)-one (mixture of 64+65) (40 mg, 97% purity, 24% yield) as white solid.
LCMS (ESI) calcd for C22H28F3N7O3[M+H]+m/z 496.22, found 496.
Chiral resolution of 3-methyl-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-2,3,4,6-tetrahydropyrido[2,3-d]pyridazin-5(1H)-one (64 and 65) Compound 64+65 was separated by SFC (Column: Daicel CHIRALPAK OJ-H 250 mm×20 mm I.D., 5 mm; Mobile phase: CO2/MeOH [0.2% (NH3)]=70/30) and concentrated under reduced pressure to afford the first fraction as 64 (20.5 mg, 99% purity, ee %: 100, white solid) and the second fraction as 65 (16.1 mg, 100% purity, ee %: 99, white solid) Although two fractions were obtained it was not possible from this information to assign absolute stereochemistry to each enantiomer.
1H NMR (400 MHz, DMSO-d6, ppm) δ:12.02 (s, 1H), 8.73 (d, J=0.8 Hz, 2H), 7.72 (s, 1H), 3.87-3.76 (m, 4H), 3.65 (t, J=6.4 Hz, 2H), 3.61-3.44 (m, 8H), 3.26-3.22 (m, 1H), 2.94-2.86 (m, 1H), 2.57 (t, J=6.4 Hz, 2H), 2.54-2.52 (m, 1H), 1.90-1.79 (m, 2H), 0.95 (d, J=6.4 Hz, 3H).
LCMS (ESI) calcd for C22H28F3N7O3[M+H]+m/z 496.22, found 496.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.02 (s, 1H), 8.73 (d, J=0.8 Hz, 2H), 7.72 (s, 1H), 3.87-3.76 (m, 4H), 3.66 (t, J=6.4 Hz, 2H), 3.60-3.45 (m, 8H), 3.27-3.21 (m, 1H), 2.95-2.87 (m, 1H), 2.57 (t, J=6.6 Hz, 2H), 2.54-2.51 (m, 1H), 1.91-1.77 (m, 2H), 0.95 (d, J=6.4 Hz, 3H).
LCMS (ESI) calcd for C22H28F3N7O3[M+H]+m/z 496.22, found 496.
To a solution of 3-(2-(1-oxo-1,2-dihydrophthalazin-5-yl)propoxy)propanoic acid 1601 (150 mg, 0.543 mmol) in DCM (15 mL) were added 2-(piperazin-1-yl)-5-(trifluoromethyl)pyrimidine hydrochloride (220 mg, 0.814 mmol), DIPEA (351 mg, 2.715 mmol), T3P (50% in EtOAc, 518 mg, 0.814 mmol) at room temperature successively. The mixture was kept stirring at room temperature for 1 h. The resulting mixture was diluted with water and extracted with DCM (30 mL×3). The combined organic layer was dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 40-60) to give 5-(1-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy) propan-2-yl)phthalazin-1(2H)-one (mixture of 72 and 73) (80 mg, 99% purity, 30% yield) as a white solid.
LCMS (ESI) calcd for C23H25F3N6O3[M+H]+ m/z 491.20, found 491.
Compound 72+73 was separated by SFC (Column: Daicel CHIRALPAK AS-H 250 mm×20 mm I.D., 5 mm; Mobile phase: CO2/MeOH [0.1% (NH3)]=70/30) and concentrated under reduced pressure to afford the first fraction as 72 (34.9 mg, 100% purity, ee %: 100, white solid) and the second fraction as 73 (37.2 mg, 99% purity, ee %: 100, white solid)
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.64 (s, 1H), 8.72 (d, J=0.8 Hz, 2H), 8.58 (s, 1H), 8.09 (d, J=7.6 Hz, 1H), 7.87-7.82 (m, 1H), 7.80-7.75 (m, 1H), 3.84-3.61 (m, 9H), 3.52-3.44 (m, 4H), 2.56-2.53 (m, 2H), 1.26 (d, J=6.8 Hz, 3H).
LCMS (ESI) calcd for C23H25F3N6O3[M+H]+ m/z 491.20, found 491.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.64 (s, 1H), 8.72 (d, J=0.7 Hz, 2H), 8.58 (s, 1H), 8.09 (d, J=7.6 Hz, 1H), 7.88-7.83 (m, 1H), 7.80-7.75 (m, 1H), 3.83-3.61 (m, 9H), 3.51-3.43 (m, 4H), 2.56-2.52 (m, 2H), 1.26 (d, J=6.8 Hz, 3H).
LCMS (ESI) calcd for C23H25F3N6O3[M+H]+ m/z 491.20, found 491.
To a stirred solution of NaH (60% in oil, 3.2 g, 80.0 mmol) in THF (100 mL) at 0° C. was added ethyl 2,4-dimethyl-1H-pyrrole-3-carboxylate 1701 (2 g, 11.8 mmol) in portions. After stirring at 0° C. for 15 min, ethyl 2-bromoacetate (10.1 g, 60.9 mmol) was added dropwise and the reaction was warmed to rt and stirred for 16 h. The reaction was quenched with saturated aqueous NH4Cl and extracted with EtOAc (50 mL×4). The combined organic layers were washed with brine (30 mL), dried over Na2SO4 and concentrated in vacuo. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 95:5) to afford ethyl 1-(2-ethoxy-2-oxoethyl)-2,4-dimethyl-1H-pyrrole-3-carboxylate 1702 (2.63 g, 98% purity, 72% yield) as an off-white solid.
LCMS (ESI) calcd for C13H19NO4 [M+H]+ m/z 254.13, found 254.10.
Ethyl 1-(2-ethoxy-2-oxoethyl)-2,4-dimethyl-1H-pyrrole-3-carboxylate 1702 (2.63 g, 10.38 mmol) was dissolved in THE (120 mL) under stirring, followed by addition a solution of AcOH (120 mL) and H2O (120 mL). The mixture was homogeneously stirred at 0° C. and added with CAN (33.66 g, 61.54 mol) in one portion. After stirring at rt for 1 h, the reaction mixture was poured into ice-water (120 mL) and stirred for another 30 min. The resulting solution was extracted with EtOAc (20 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 90:10) to obtain the title compound ethyl 1-(2-ethoxy-2-oxoethyl)-2-formyl-4-methyl-1H-pyrrole-3-carboxylate 1703 (1.20 g, 98% purity, 46% yield) as a white solid.
To a solution of ethyl 1-(2-ethoxy-2-oxoethyl)-2-formyl-4-methyl-1H-pyrrole-3-carboxylate 1703 (1.20 g, 4.47 mmol) in AcOH (5 mL) was added H2NNH2·H2O (80% wt, 0.46 g, 6.73 mmol) in one portion. The reaction mixture was heated with stirring at 100° C. for 1 h. Most of the solvent was removed by evaporation (55° C.) under reduced pressure. The resulting solution was extracted with EtOAc (20 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 50:50) to obtain the title compound ethyl 2-(3-methyl-4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1704 (603 mg, 97% purity, 47% yield) as a white solid.
LCMS (ESI) calcd for C11H13N3O3 [M+H]+ m/z 236.10, found 236.
To a solution ethyl 2-(3-methyl-4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1704 (603 mg, 2.58 mmol) and DIPEA (1664 mg, 12.8 mmol) in DMF (42 mL) at rt, SEMCl (2127 mg, 12.8 mmol) was added in one portion. After completing the addition, the reaction solution was heated at 80° C. for 1 h. The resulting reaction solution was poured into cold water and then extracted with EtOAc (20 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 60:40) to give ethyl 2-(3-methyl-4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1705 (565 mg, 98% purity, 82% yield) as a white solid.
LCMS (ESI) calcd for C17H27N3O4Si [M+H]+ m/z 366.18, found 366.15.
To a suspension of LiAlH4 (55 mg, 1.449 mmol) in THE (5 mL), ethyl 2-(3-methyl-4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1705 (350 mg, 0.956 mmol) in THE (5 mL) was added dropwise under N2 atmosphere, in which the temperature was kept at 0˜5° C. The reaction mixture was stirred at this temperature for a further 1 h. After the dropwise addition of water (0.1 mL) and 13% aq. NaOH (0.2 mL) successively, the mixture was stirred for additional 30 min. The resulting mixture was filtered through diatomaceous earth and the filter cake was thoroughly washed with DCM. The filtrate was concentrated to dryness under reduced pressure. The residue was purified by flash chromatography (eluting with DCM/MeOH=100:0 to 90:10) to obtain 1-(2-hydroxyethyl)-3-methyl-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1706 (280 mg, 98% purity, 75% yield) as a yellow oil.
LCMS (ESI) calcd for C15H25N3O3Si [M+H]+ m/z 324.17, found 324.15.
A round-bottom flask containing a mixture of 1-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-2-yn-1-one (80 mg, 0.282 mmol), 1-(2-hydroxyethyl)-3-methyl-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1706 (90 mg, 0.279 mmol) and P(n-Bu)3 (49 mg, 0.241 mmol) in the DCM (9 mL) was placed in oil bath heated to 25° C. and stirred under 25° C. of 18 h. The resulting reaction solution was poured into cold water and then extracted with DCM (100 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with DCM/MeOH=100:0 to 90:10) to give of (E)-3-methyl-1-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1707 (172 mg, 98% purity, 79% yield) as a yellow solid.
LCMS (ESI) calcd for C27H36F3N7O4Si [M+H]+ m/z 608.26, found 608.25.
A mixture of compound (E)-3-methyl-1-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1707 (152 mg, 0.250 mmol) and Pd/C (31 mg) in MeOH (20 mL) was stirred under 1 atm at room temperature for 6 hour. The resulting mixture was filtered through diatomaceous earth. The filtrate was concentrated to dryness under reduced pressure. The residue was purified by flash chromatography (eluting with DCM/MeOH=100:0 to 98:2) to 3-methyl-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1708 (120 mg, 98% purity, 78% yield) as a yellow solid.
LCMS (ESI) calcd for C27H38F3N7O4Si [M+H]+ m/z 610.27, found 610.30.
A round-bottom flask containing a mixture of 3-methyl-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-5((2(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1708 (120-mg, 0.197 mmol) and HCl-Dioxane (4 M, 10 mL) was stirred at rt for 2 h. The resulting mixture was concentrated to dryness under reduced pressure. The residue was purified by C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 30-70) to to 3-methyl-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 74 (40 mg, 99% purity, 40% yield) as a white solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ:12.04 (s, 1H), 8.73 (d, J=0.8 Hz, 2H), 8.24 (s, 1H), 7.14 (d, J=0.8 Hz, 1H), 4.29 (t, J=5.0 Hz, 2H), 3.84-3.74 (m, 4H), 3.69 (t, J=5.0 Hz, 2H), 3.63 (t, J=6.4 Hz, 2H), 3.56-3.46 (m, 4H), 2.56-2.51 (m, 2H), 2.30 (s, 3H).
LCMS (ESI) calcd for C21H24F3N7O3[M+H]+ m/z 480.19, found 480.25.
To a solution of ethyl 2-methyl-1H-pyrrole-3-carboxylate 1801 (10 g, 0.065 mol) in THE (100 mL) were added ethyl 2-bromoacetate (16.3 g, 0.097 mol), NaH (60% in oil, 3.9 g, 0.097 mol) at 0° C. After completion of addition, the reaction solution was warmed to rt and kept stirring at rt for an additional 16 h. Water was added to quench the reaction. The obtained solution was extracted with EtOAc (50 mL×4). The combined organic phase was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 50:50) to give ethyl 1-(2-ethoxy-2-oxoethyl)-2-methyl-1H-pyrrole-3-carboxylate 1802 (14 g, 90% purity, 80% yield) as yellow solid.
LCMS (ESI) calcd for C12H17NO4 [M+H]+ m/z 240.12, found 240.
To a stirred solution of ethyl 1-(2-ethoxy-2-oxoethyl)-2-methyl-1H-pyrrole-3-carboxylate 1802 (10 g, 0.041 mol) in THF: CH3COOH:H2O (1:1:1, 150 mL) was added CAN (91.6 g, 0.167 mol) at rt. The reaction mixture was stirred at room temperature for 6 h. The reaction mixture was poured carefully into an ice bath-cooled solution, and then extracted with EtOAc (2×500 mL). The combined extracts were washed with NaHCO3 solution (500 mL). The organic layer dried over sodium sulfate and concentrated under reduced pressure to give crude. The crude was purified by flash column chromatography (eluting with PE/EtOAc=99:1 to 50:50) to afford ethyl 1-(2-ethoxy-2-oxoethyl)-2-formyl-1H-pyrrole-3-carboxylate 1803 (6 g, 90% purity, 50% yield) as yellow oil.
LCMS (ESI) calcd for C12H15NO5 [M+H]+ m/z 254.10, found 254.
To the solution of ethyl 1-(2-ethoxy-2-oxoethyl)-2-formyl-1H-pyrrole-3-carboxylate 1803 (3.0 g, 0.011 mol) in MeCN (50 mL) was added NBS (1.0 g, 0.005 mmol) at rt. The mixture was kept stirring at room temperature for 1 h. The resulting mixture was diluted with water and extracted with DCM (30 mL×3). The combined organic layer was dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 70:30) to give ethyl 4-bromo-1-(2-ethoxy-2-oxoethyl)-2-formyl-1H-pyrrole-3-carboxylate 1804 (1 g, 90% purity, 22% yield) as yellow oil.
LCMS (ESI) calcd for C12H14BrNO5 [M+H]+ m/z 332.01, found 332, 334.
To a solution of ethyl 4-bromo-1-(2-ethoxy-2-oxoethyl)-2-formyl-1H-pyrrole-3-carboxylate 1804 (1.2 g, 0.003 mol) in AcOH (20 mL) was added H2NNH2·H2O (80% wt, 0.54 g, 0.010 mol) at rt. The mixture was kept stirring at 80° C. for 1 h. The resulting light brown solution was concentrated under reduced pressure to remove most AcOH. The residue was diluted with DCM (50 mL) and then adjusted PH to 8 with saturated aqueous NaHCO3 at 0° C. The basified solution was extracted with DCM (10 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure to give ethyl 2-(3-bromo-4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1805 (1.1 g, 90% purity, 91% yield) as yellow solid.
LCMS (ESI) calcd for C110H10BrN3O3[M+H]+ m/z 299.99, found 300, 302.
To a solution of ethyl 2-(3-bromo-4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1805 (2 g, 0.006 mol), DIPEA (2.6 g, 0.020 mol) in DMF (30 mL) was added SEMCl (2.2 g, 0.013 mol) at rt. Then the reaction mixture was stirred 80° C. for 1 h. After cooling to room temperature, the reaction mixture was poured into cold water and then extracted with EtOAc (50 mL×4). The combined organic layer was washed three times with brine solution, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 40:60) to afford ethyl 2-(3-bromo-4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1806 (2 g, 90% purity, 62% yield) as yellow oil.
LCMS (ESI) calcd for C16H24BrN3O4Si [M+H]+ m/z 430.07, found 430, 432.
To a stirred solution of ethyl 2-(3-bromo-4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1806 (300 mg, 0.69 mmol), CuI (131 mg, 0.69 mmol), HMPA (621 mg, 3.45 mmol) in NMP (10 mL) was added methyl 2,2-difluoro-2-(fluorosulfonyl)acetate (662 mg, 3.45 mmol) at rt. The solution was then stirred in a microwave at 160° C. for 1 h. The resulting reaction solution was filtered and the filtrate was purified directly by flash silica chromatography (eluting with PE/EtOAc=100:0 to 50:50) to give ethyl 2-(4-oxo-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1807 (150 mg, 30% purity, 12% yield) as yellow oil.
LCMS (ESI) calcd for C17H24F3N3O4Si [M+H]+ m/z 420.15, found 420.
To a solution of ethyl 2-(4-oxo-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)acetate 1807 (900 mg, 2.13 mmol) in MeOH (20 mL) were added LiCl (362 mg, 8.54 mmol), NaBH4 (323 mg, 8.54 mmol) at rt successively. The reaction mixture was stirred at rt for 1 h. The resulting mixture was quenched with water and extracted with DCM (50 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=100:0 to 50:50) to obtain 1-(2-hydroxyethyl)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1808 (150 mg, 90% purity, 16% yield) as colorless oil.
LCMS (ESI) calcd for C15H22F3N3O3Si [M+H]+ m/z 378.14, found 378.15.
To a solution of 1-(2-hydroxyethyl)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1808 (100 mg, 0.26 mmol), 1-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-2-yn-1-one (112 mg, 0.39 mmol) in DCM (10 mL) was added P(n-Bu)3 (5 mg, 0.026 mmol) at rt. The reaction mixture was stirred at rt for 1 h. The resulting mixture was quenched with water and extracted with DCM (50 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=100:0 to 0:100) to obtain (E)-1-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1809 (180 mg, 90% purity, 92% yield) as colorless oil.
LCMS (ESI) calcd for C27H33F6N7O4Si [M+H]+ m/z 662.23, found 662.25.
A solution of (E)-1-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1809 (150 mg, 0.22 mmol) and Pd/C (30 mg) in MeOH/DCM (15 mL, 2:1) was stirred at rt for 1 h under H2 atmosphere. The resulting solution was filtered through diatomaceous earth and the filter cake was washed with DCM (5 mL×4). The filtrate was concentrated under reduced pressure to give 1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1810 (140 mg, 90% purity, 83% yield) as colorless oil.
LCMS (ESI) calcd for C27H35F6N7O4Si [M+H]+ m/z 664.24, found 664.25.
To a solution of 1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 1810 (100 mg, 0.15 mmol) in HCl-Dioxane (4 M, 40 mL) was stirred at rt for 16 h. The resulting reaction solution was basified (PH 8) by saturated aqueous NaHCO3 at 0° C. and then extracted with EtOAc (50 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The crude was purified by C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 30-60) to give 1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 131 (21.5 mg, 98% purity, 23% yield) as white solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ:12.56 (s, 1H), 8.73 (s, 2H), 8.43 (s, 1H), 8.01 (s, 1H), 4.44 (t, J=4.4 Hz, 2H), 3.82-3.71 (m, 6H), 3.66 (t, J=6.0 Hz, 2H), 3.55-3.45 (m, 4H), 2.54-2.52 (m, 2H).
LCMS (ESI) calcd for C21H21F6N7O3 [M+H]+ m/z 534.16, found 534.
To a solution of 4,5-dichloropyridazin-3(2H)-one 1901 (8 g, 48.5 mmol) in DMF (100 mL) were added PMBCl (19 g, 121.3 mmol) and DIPEA (31.4 g, 242.5 mmol) at room temperature. The resulting mixture was stirred at 50° C. for 6 h. After cooling to room temperature, water (400 mL) was added, and the mixture was extracted EtOAc (3×150 mL). The combined organic layers were dried (Na2SO4), concentrated in vacuo. The residue was purified by flash chromatography (silica gel, eluting with PE/EtOAc=100:0 to 80:20) to obtain 4,5-dichloro-2-(4-methoxybenzyl) pyridazin-3(2H)-one 1902 (8 g, 90% purity, 52% yield) as white solid.
LCMS (ESI) calcd for C12H10Cl2N2O2 [M+H]+ m/z 285.02, found 285.
To a solution of 4,5-dichloro-2-(4-methoxybenzyl) pyridazin-3(2H)-one 1902 (8 g, 28.1 mmol) in EtOH (100 mL) and H2O (50 mL) was added dimethylamine in MeOH (2 M, 70.5 mL) at room temperature. The reaction mixture was stirred at 50° C. for 4 h. After cooling to room temperature, the mixture was concentrated in vacuo. Water (100 mL) was added, and the mixture was extracted EtOAc (3×150 mL). The combined organic layers were dried (Na2SO4), concentrated in vacuo, and purified by flash chromatography (silica gel, eluting with PE/EtOAc=100:0 to 20:80) to obtain 4-chloro-5-(dimethylamino)-2-(4-methoxybenzyl) pyridazin-3(2H)-one 1903 (8 g, 85% purity, 82% yield) as white solid.
LCMS (ESI) calcd for C14H16ClN3O2[M+H]+ m/z 294.1, found 294.
To a solution of 4-chloro-5-(dimethylamino)-2-(4-methoxybenzyl) pyridazin-3(2H)-one 1903 (8 g, 27.2 mmol) in ACN (100 mL) were added tributyl(vinyl) stannane (17.3 g, 54.4 mmol) and Pd(AMPHOS)Cl2 (1.93 g, 2.72 mmol) at room temperature. The resulting mixture was stirred at 100° C. for 10 h. After cooling to room temperature, the mixture was concentrated in vacuo. The residue was purified by flash chromatography (silica gel, eluting with PE/EtOAc=100:0 to 10:90) to obtain 5-(dimethylamino)-2-(4-methoxybenzyl)-4-vinylpyridazin-3(2H)-one 1904 (6 g, 90% purity, 69% yield) as white solid.
LCMS (ESI) calcd for C16H19N3O2 [M+H]+ m/z 286.16, found 286.
To a solution of 5-(dimethylamino)-2-(4-methoxybenzyl)-4-vinylpyridazin-3(2H)-one 1904 (3 g, 0.01 mol) in MeOH/H2O (2:1, 30 mL) were added K2OsO4·2H2O (0.39 g, 0.001 mol), NaIO4 (8.9 g, 0.04 mol) at rt. The reaction mixture was stirred at rt for 1 h. The resulting mixture was quenched with water and extracted with DCM (50 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=100:0 to 50:50) to give 5-(dimethylamino)-2-(4-methoxybenzyl)-3-oxo-2,3-dihydropyridazine-4-carbaldehyde 1905 (1.8 g, 90% purity, 53% yield) as yellow oil.
LCMS (ESI) calcd for C15H17N3O3[M+H]+ m/z 288.13, found 288.10.
To a solution of 5-(dimethylamino)-2-(4-methoxybenzyl)-3-oxo-2,3-dihydropyridazine-4-carbaldehyde 1905 (1.8 g, 0.006 mol), trimethyl(trifluoromethyl)silane (0.9 g, 0.006 mol) in THE (20 mL) was added TBAF in THF (1 M, 0.6 mL) at rt. The reaction mixture was stirred at rt for 1 h. The resulting mixture was quenched with water and extracted with DCM (50 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=100:0 to 30:70) to obtain 5-(dimethylamino)-2-(4-methoxybenzyl)-4-(2,2,2-trifluoro-1-hydroxyethyl)pyridazin-3(2H)-one 1906 (1.6 g, 90% purity, 63% yield) as yellow oil.
LCMS (ESI) calcd for C16H18F3N3O3[M+H]+ m/z 358.13, found 358.10.
To a solution of 5-(dimethylamino)-2-(4-methoxybenzyl)-4-(2,2,2-trifluoro-1-hydroxyethyl)pyridazin-3(2H)-one 1906 (1.6 g, 0.004 mol) in DCM (30 mL) was added Dess-Martin periodinane (3.8 g, 0.009 mol) at rt. The reaction mixture was stirred at rt for 1 h. The resulting mixture was quenched with water and extracted with DCM (50 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=100:0 to 50:50) to obtain 5-(dimethylamino)-2-(4-methoxybenzyl)-4-(2,2,2-trifluoroacetyl)pyridazin-3(2H)-one 1907 (1.5 g, 90% purity, 84% yield) as yellow oil.
LCMS (ESI) calcd for C16H16F3N3O3[M+H]+ m/z 356.11, found 356.10.
To a solution of 5-(dimethylamino)-2-(4-methoxybenzyl)-4-(2,2,2-trifluoroacetyl)pyridazin-3(2H)-one 1907 (1.6 g, 0.004 mol) in EtOH (30 mL) was added H2NNH2·H2O (80% wt, 1.0 g, 0.020 mol) at rt. The reaction mixture was stirred at 80° C. for 3 h. The resulting light brown solution was concentrated under reduced pressure to remove most EtOH to get crude. The crude was purified by C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 30-60) to give 5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 1908 (0.9 g, 90% purity, 55% yield) as white solid.
LCMS (ESI) calcd for C14H11F3N4O2 [M+H]+ m/z 325.08, found 325.05.
To a solution of 5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 1908 (200 mg, 0.61 mmol), ethyl 2-bromoacetate (308 mg, 1.84 mmol) was added t-BuOK (206 mg, 1.84 mmol) at 0° C. The reaction mixture was stirred at rt for 1 h. The reaction solution was quenched with water and extracted with EtOAc (20 mL×3). The organic phase was concentrated and purified by silica gel column (eluting with PE/EtOAc=100:0 to 50:50) to obtain ethyl 2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)acetate 1909 (200 mg, 90% purity, 71% yield) as yellow oil.
LCMS (ESI) calcd for C1H17F3N4O4[M+H]+ m/z 411.12, found 411.10.
To a solution of ethyl 2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)acetate 1909 (200 mg, 0.48 mmol) in MeOH (20 mL) were added LiCl (82 mg, 1.94 mmol), NaBH4 (73 mg, 1.94 mmol) at rt. The reaction mixture was stirred at rt for 1 h. The resulting mixture was quenched with water and extracted with EtOAc (50 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=100:0 to 50:50) to obtain 1-(2-hydroxyethyl)-5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 1910 (140 mg, 90% purity, 70% yield) as yellow oil.
LCMS (ESI) calcd for C16H15F3N4O3[M+H]+ m/z 369.11, found 369.05.
To a solution of 1-(2-hydroxyethyl)-5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 1910 (140 mg, 0.37 mmol), 1-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-2-yn-1-one (108 mg, 0.37 mmol) in DCM (10 mL) was added P(n-Bu)3 (15 mg, 0.075 mmol) at rt. The reaction mixture was stirred at rt for 1 h. The resulting mixture was quenched with water and extracted with DCM (50 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=100:0 to 0:100) to obtain (E)-5-(4-methoxybenzyl)-1-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 1911 (200 mg, 90% purity, 72% yield) as yellow oil.
LCMS (ESI) calcd for C28H26F6N8O4[M+H]+ m/z 653.20, found 653.
A solution of (E)-5-(4-methoxybenzyl)-1-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 1911 (150 mg, 0.22 mmol) and Pd/C (30 mg) in MeOH/DCM (15 mL, 2:1) was stirred at rt for 1 h under H2 atmosphere. The resulting solution was filtered through diatomaceous earth and the filter cake was washed with DCM (5 mL×4). The filtrate was concentrated under reduced pressure to give 5-(4-methoxybenzyl)-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 1912 (140 mg, 90% purity, 83% yield) as yellow oil.
LCMS (ESI) calcd for C28H28F6N8O4[M+H]+ m/z 655.21, found 655.
To a solution of 5-(4-methoxybenzyl)-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 1912 (140 mg, 0.21 mmol) in TFA (10 mL) was added TfOH (64 mg, 0.42 mmol) at rt. The reaction mixture was stirred at rt for 1 h. The resulting mixture was diluted with DCM (50 mL) and then adjusted PH to 8 with saturated aqueous NaHCO3 at 0° C. The basified solution was extracted with DCM (10 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The crude product was purified by C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 30-60) to give 1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 153 (47 mg, 99% purity, 40% yield) as white solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ:12.85 (s, 1H), 8.73 (s, 2H), 8.58 (s, 1H), 4.70 (t, J=4.8 Hz, 2H), 3.82 (t, J=5.0 Hz, 2H), 3.79-3.73 (m, 4H), 3.63 (t, J=6.2 Hz, 2H), 3.50-3.43 (m, 4H), 2.49-2.46 (m, 2H).
LCMS (ESI) calcd for C20H20F6N8O3[M+H]+ m/z 535.16, found 535.20.
To a solution of 5-bromo-7-chloro-2-((2-(trimethylsilyl)ethoxy)methyl)phthalazin-1(2H)-one 2001 (400 mg, 1.02 mmol) in ACN (10 mL) were added allyltributylstannane (339 mg, 1.02 mmol) and Pd(AMPHOS)Cl2 (73 mg, 0.10 mmol) at rt under N2. The reaction mixture was stirred at 100° C. for 1 h in a sealed tube. The reaction mixture was concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=80:20 to 70:30) to obtain 5-allyl-7-chloro-2-((2-(trimethylsilyl)ethoxy)methyl)phthalazin-1(2H)-one 2002 (300 mg, 90% purity, 75% yield) as colorless oil.
LCMS (ESI) calcd for C17H23ClN2O2Si [M+H]+ m/z 351.12, found 351.15
To a solution of 5-allyl-7-chloro-2-((2-(trimethylsilyl)ethoxy)methyl)phthalazin-1(2H)-one 2002 (1.0 g, 2.8 mmol) in MeOH/H2O (3:1, 40 mL) were added K2OsO4·2H2O (100 mg, 0.28 mmol) and NaIO4 (2.4 g, 11.2 mmol) at 0° C. successively. The reaction mixture was stirred at rt for 1 h. The resulting mixture was quenched with water and extracted with EtOAc (50 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure to give crude 2-(7-chloro-1-oxo-2-((2-(trimethylsilyl)ethoxy)methyl)-1,2-dihydrophthalazin-5-yl)acetaldehyde 2003 (500 mg, 80% purity, 39% yield) as yellow oil.
LCMS (ESI) calcd for C16H21ClN2O3Si [M−27]+ m/z 325.10, found 325.
To a solution of 2-(7-chloro-1-oxo-2-((2-(trimethylsilyl)ethoxy)methyl)-1,2-dihydrophthalazin-5-yl)acetaldehyde 2003 (500 mg, 1.41 mmol) in methanol was added NaBH4 (160 mg, 4.24 mmol) in portions at rt. The reaction mixture was stirred at rt for 1 h. The resulting mixture was quenched with water and extracted with EtOAc (50 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=100:0 to 60:40) to obtain 7-chloro-5-(2-hydroxyethyl)-2-((2-(trimethylsilyl)ethoxy)methyl)phthalazin-1(2H)-one 2004 (413 mg, 90% purity, 74% yield) as a white solid.
LCMS (ESI) calcd for C16H23ClN2O3Si [M+H]+ m/z 355.12, found 355.
To a solution of 7-chloro-5-(2-hydroxyethyl)-2-((2-(trimethylsilyl)ethoxy)methyl)phthalazin-1(2H)-one 2004 (410 mg, 1.16 mmol) and ethyl propiolate (114 mg, 1.16 mmol) in DCM (20 mL) was added P(n-Bu)3 (117 mg, 0.58 mmol) at rt. The reaction mixture was stirred at rt for 1 h. The resulting mixture was quenched with water and extracted with DCM (50 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=100:0 to 60:40) to obtain ethyl (E)-3-(2-(7-chloro-1-oxo-2-((2-(trimethylsilyl)ethoxy)methyl)-1,2 dihydrophthalazin-5-yl)ethoxy)acrylate 2005 (262 mg, 90% purity, 45% yield) as white solid.
LCMS (ESI) calcd for C21H29ClN2O5Si [M+Na]+ m/z 475.15, found 475.
To a solution of ethyl (E)-3-(2-(7-chloro-1-oxo-2-((2-(trimethylsilyl)ethoxy)methyl)-1,2 dihydrophthalazin-5-yl)ethoxy)acrylate 2005 (240 mg, 0.53 mmol) in toluene(10 mL) was added RhCl(PPh3)3(25 mg) at rt. The reaction mixture was stirred at 50° C. for 2 h under H2 atmosphere. The reaction solution was concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=100:0 to 50:50) to obtain ethyl 3-(2-(7-chloro-1-oxo-2-((2-(trimethylsilyl)ethoxy)methyl)-1,2-dihydrophthalazin-5-yl)ethoxy)propanoate 2006 (250 mg, 90% purity, 93% yield) as colorless oil.
LCMS (ESI) calcd for C21H31ClN2O5Si [M+Na]+ m/z 477.17, found 477.
A solution of ethyl 3-(2-(7-chloro-1-oxo-2-((2-(trimethylsilyl)ethoxy)methyl)-1,2-dihydrophthalazin-5-yl)ethoxy)propanoate 2006 (350 mg, 0.77 mmol) in HCl-Dioxane (4 M, 20 mL) was stirred at rt for 16 h. The mixture was concentrated under reduced pressure to obtain crude ethyl 3-(2-(7-chloro-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)propanoate 2007 (152 mg, 90% purity, 55% yield) as colorless oil.
LCMS (ESI) calcd for C15H17ClN2O4 [M+H]+ m/z 325.09, found 325.
To a solution of ethyl 3-(2-(7-chloro-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)propanoate 2007 (150 mg, 0.46 mmol) in THF/H2O (15 mL, 1:1) was added LiOH (58 mg, 0.14 mmol). The mixture was stirred at room temperature for 2 h. THE was removed under reduced pressure and the aqueous phase was acidified with 1 M HCl aq. to pH=4˜5. The resulting solid was collected by filtration and dried in vacuo to obtain 3-(2-(7-chloro-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)propanoic acid 2008 (58 mg, 95% purity, 40% yield) as a white solid.
LCMS (ESI) calcd for C13H13ClN2O4 [M+H]+ m/z 297.06, found 297.
To a solution 3-(2-(7-chloro-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)propanoic acid 2008 (29 mg, 0.10 mmol), 2-(piperazin-1-yl)-5-(trifluoromethyl) pyrimidine hydrochloride (25 mg, 0.11 mmol) in DCM (5 mL) were added DIPEA (51 mg, 0.39 mmol), T3P (50% wt in EtOAc, 124 mg, 0.20 mmol) at rt. The reaction mixture was stirred at rt for 1 h. The reaction solution was quenched with water (20 mL) and extracted with DCM (20 mL×3). The organic phase was concentrated and purified by prep-HPLC (columns: Gemini 5 um C18 150×21.2 mm, mobile phase: ACN-H2O (0.1% FA), gradient: 40-95) to obtain 7-chloro-5-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)phthalazin-1(2H)-one 80 (19.3 mg, 99% purity, 38% yield) as a white solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.82 (s, 1H), 8.73 (d, J=0.8 Hz, 2H), 8.51 (s, 1H), 8.03 (d, J=2.0 Hz, 1H), 7.86 (d, J=2.0 Hz, 1H), 3.81-3.74 (m, 4H), 3.73-3.63 (m, 4H), 3.54-3.48 (m, 4H), 3.25 (t, J=6.2 Hz, 2H), 2.56 (t, J=6.4 Hz, 2H).
LCMS (ESI) calcd for C22H22ClF3N6O3 [M+H]+ m/z 511.14, found 511.
To a stirred mixture of 2-chloro-5-(trifluoromethyl)pyridine 2101 (500 mg, 2.739 mmol) in DMSO (10 mL) was added tert-butyl piperazine-1-carboxylate (513 mg, 2.739 mmol) and potassium carbonate (946 mg, 6.8475 mmol). The resulting mixture was stirred 5 hours at 100° C. The reaction was monitored by TLC. After the reaction was completed, the mixture was cooled to room temperature and diluted with ethyl acetate (30 mL). the reaction was filtered and the filtrate was washed with saturated NaHCO3 solution (2×10 mL). The organic phase was dried over Na2SO4, filtered and concentrated under reduced pressure. The residue obtained was purified by silica gel column chromatography (eluting with PE/EtOAc=100:0 to 85:15). to afford tert-butyl 4-(5-(trifluoromethyl)pyridin-2-yl)piperazine-1-carboxylate 2102 (600 mg, 90% purity, 59% yield) as a white solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 8.42 (s, 1H), 7.82 (dd, J=9.1, 2.5 Hz, 1H), 6.95 (d, J=9.1 Hz, 1H), 3.63 (dd, J=6.3, 4.3 Hz, 4H), 3.49-3.36 (m, 4H), 1.42 (s, 9H).
A mixture of tert-butyl 4-(5-(trifluoromethyl)pyridin-2-yl)piperazine-1-carboxylate 2102 (300 mg, 0.9 mmol) was added to 4M HCl/dioxane (10 mL), the mixture was stirred for 5 hours at 20° C. The reaction was monitored by LCMS. After the reaction was completed, the reaction mixture was concentrated under reduced pressure to afford 1-(5-(trifluoromethyl)pyridin-2-yl)piperazine 2103 (210 mg, 90% purity, 78% yield) as white solid. The crude mixture was directly used for the next step without further purification.
LCMS: (ESI) calcd for C10H12F3N3 [M+H]+ m/z 232.10, found 232.
To a stirred solution of 1-(5-(trifluoromethyl)pyridin-2-yl)piperazine 2103 (60 mg, 0.2233 mmol) in DCM (5 mL) was added 3-[2-(1-oxo-2H-phthalazin-5-yl)ethoxy]propanoic acid 2104 (59 mg, 0.2233 mmol), T3P (107 mg, 0.3349 mmol) and DIPEA (87 mg, 0.6699 mmol). The reaction mixture was stirred for 2 hours at 20° C. The reaction was monitored by LCMS. After the reaction was completed, the resulting mixture was diluted with water and extracted with DCM (30 mL×3). The combined organic layer was dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by pre-HPLC (columns: Gemini 5 um C18 150*21.2 mm, mobile phase: ACN-H2O (0.1% FA), gradient: 20-95) to obtain 5-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyridin-2-yl)piperazin-1-yl)propoxy)ethyl)phthalazin-1(2H)-one 98 (51.8 mg, 95% purity, 46% yield) as a white solid.
1H NMR: (400 MHz, DMSO) δ 12.66 (s, 1H), 8.51 (s, 1H), 8.43 (s, 1H), 8.10 (d, J=7.7 Hz, 1H), 7.89-7.62 (m, 3H), 6.94 (d, J=9.1 Hz, 1H), 3.68 (m, 4H), 3.61 (m, 4H), 3.53 (s, 4H), 3.24 (t, J=5.9 Hz, 2H), 2.57 (t, J=6.3 Hz, 2H).
LCMS: (ESI) calcd for C23H24F3N5O3[M+H]+ m/z 476.18, found 476.
To a solution of 5-bromo-7-chloro-2-(4-methoxybenzyl)phthalazin-1(2H)-one 2201 (620 mg, 1.63 mmol) in Dioxane (15 mL) at room temperature were added tributyl(1-ethoxyvinyl)stannane 2202 (141 mg, 1.63 mmol), CuI (31 mg, 0.16 mmol) and Pd(PPh3)4 (189 mg, 0.16 mmol) successively. The reaction mixture was stirred at 100° C. for 1 h under N2 atmosphere. The reaction mixture was poured into cold water and then extracted with EtOAc (50 mL×3). The combined organic layer was dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=100:0 to 70:30) to obtained 7-chloro-5-(1-ethoxyvinyl)-2-(4-methoxybenzyl)phthalazin-1(2H)-one 2203 (410 mg, 90% purity, 61% yield) as a yellow solid.
LCMS (ESI) calcd for C20H19ClN2O3[M+H]+ m/z 371.11, found 371.15
A solution of 7-chloro-5-(1-ethoxyvinyl)-2-(4-methoxybenzyl)phthalazin-1(2H)-one 2203 (400 mg, 1.08 mmol) in DCM (5 mL) was added HCl-Dioxane (4 M, 5 mL) at rt. The reaction solution was stirred at rt for 4 h. The resulting reaction mixture was evaporated under reduced pressure and the residue was purified by flash column chromatography (eluting with PE/EtOAc=85:15 to 70:30) to afford 5-acetyl-7-chloro-2-(4-methoxybenzyl)phthalazin-1(2H)-one 2204 (347 mg, 90% purity, 84% yield) as a colorless oil.
LCMS (ESI) calcd for C18H15ClN2O3[M+H]+ m/z 343.08, found 343.10
To a solution of 5-acetyl-7-chloro-2-(4-methoxybenzyl)phthalazin-1(2H)-one 2204 (340 mg, 0.99 mmol) in MeOH (5 mL), NaBH4 (75 mg, 1.98 mmol) was added in portions at 0° C. The reaction was then stirred at 0° C. for 10 min. The reaction solution was poured into water (30 mL) and extracted with EtOAc (30 mL×3). The combined organic layer was washed with saturated NH4Cl solution, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=85:15 to 30:70) to give 7-chloro-5-(1-hydroxyethyl)-2-(4-methoxybenzyl)phthalazin-1(2H)-one 2205 (335 mg, 90% purity, 88% yield) as a white solid.
LCMS (ESI) calcd for C18H17ClN2O3[M+H]+m/z 345.09, found 345.10
To a solution of 7-chloro-5-(1-hydroxyethyl)-2-(4-methoxybenzyl)phthalazin-1(2H)-one 2205 (330 mg, 0.96 mmol) in n-Hexane (15 mL) was added Ag2O (887 mg, 3.83 mmol) followed by MgSO4 (459 mg, 3.83 mmol) at room temperature. The reaction mixture was heated at 80° C. for 1 h then the solution was added Ag2O (887 mg, 3.83 mmol) followed by methyl (E)-4-bromobut-2-enoate 2206 (857 mg, 4.79 mmol). The resulting solution was heated at reflux for 18 h. The reaction mixture was poured into cold water and then extracted with EtOAc (50 mL×4). The combined organic layer was dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with EtOAc/PE, 30% to 50%) to afford methyl (E)-4-(1-(7-chloro-2-(4-methoxybenzyl)-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)but-2-enoate 2207 (85 mg, 90% purity, 18% yield) as a white solid.
LCMS (ESI) calcd for C23H23ClN2O5 [M+H]+ m/z 443.13, found 443.10
To a solution of methyl (E)-4-(1-(7-chloro-2-(4-methoxybenzyl)-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)but-2-enoate 2207 (95 mg, 0.21 mmol) in toluene (5 mL) was added RhCl(PPh3)3(10 mg) at rt. The reaction mixture was stirred at 50° C. for 12 h under H2 atmosphere. After completion of reaction, the reaction mixture was concentrated under reduced pressure. The residue was purified by flash column chromatography on silica gel (eluting with PE/EtOAc=70/30 to 40/60) to obtain methyl 4-(1-(7-chloro-2-(4-methoxybenzyl)-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)butanoate 2208 (70 mg, 90% purity, 66% yield) as a white solid.
LCMS (ESI) calcd for C23H25ClN2O5[M+H]+ m/z 445.15, found 445.20
To a solution of methyl 4-(1-(7-chloro-2-(4-methoxybenzyl)-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)butanoate 2208 (70 mg, 0.16 mmol) in THF/H2O (3/1, 5 mL) was added LiOH (20 mg, 0.47 mmol) at rt. The mixture was stirred at rt for 4 h. THE was removed under reduced pressure and the aqueous phase was acidified with 1 M aqueous HCl to pH=4˜5. The precipitate was collected by filtration and dried in vacuo to obtain 4-(1-(7-chloro-2-(4-methoxybenzyl)-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)butanoic acid 2209 (55 mg, 90% purity, 73% yield) as a white solid.
LCMS (ESI) calcd for C22H23ClN2O5 [M+H]+ m/z 431.13, found 431.20
To a solution of 4-(1-(7-chloro-2-(4-methoxybenzyl)-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)butanoic acid 2209 (50 mg, 0.12 mmol), 2-(piperazin-1-yl)-5-(trifluoromethyl)pyrimidine hydrochloride (47 mg, 0.17 mmol) in DMF (10 mL) were added DIPEA (60 mg, 0.46 mmol), HATU (87 mg, 0.23 mmol) successively at rt. The reaction mixture was stirred at rt for 1 h. The reaction solution was quenched with water (20 mL) and extracted with EtOAc (20 mL×3). The organic phase was washed with brine (20 mL×3). The combined organic layers were concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=90:10 to 40:60) to obtain 7-chloro-2-(4-methoxybenzyl)-5-(1-(4-oxo-4-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)butoxy)ethyl)phthalazin-1(2H)-one 2210 (70 mg, 90% purity, 84% yield) as a white solid.
LCMS (ESI) calcd for C31H32ClF3N6O4 [M+H]+ m/z 645.21, found 645.35
To the solution of 7-chloro-2-(4-methoxybenzyl)-5-(1-(4-oxo-4-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)butoxy)ethyl)phthalazin-1(2H)-one 2210 (70 mg, 0.09 mmol) in TFA (2 mL) was added TfOH (28 mg, 0.19 mmol) at 0° C. The reaction solution was stirred at rt for 1 h. The mixture was adjusted to pH=8-9 with aqueous NaHCO3 at 0° C., then the aqueous layer was extracted with EtOAc (50 mL×3). The combined organic layers were concentrated under reduced pressure. The residue was purified by C18 column (mobile phase: ACN-H2O (0.1% FA), gradient: 10%-95%) to give 7-chloro-5-(1-(4-oxo-4-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)butoxy)ethyl)phthalazin-1(2H)-one (mixture of 174 and 175) as a white solid.
Compounds 174 and 175 were separated by SFC (Column: Daicel CHIRALPAK AS-H 250 mm×20 mm I.D., 5 um; Mobile phase: CO2/MeOH (0.1% NH3)=60/40) and concentrated under reduced pressure to afford the first fraction as 174 (5.9 mg, 99% purity, 100% ee, white solid) and the second fraction as 175 (8.2 mg, 99% purity, 98% ee, white solid).
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.90 (s, 1H), 8.73 (s, 2H), 8.67 (s, 1H), 8.13 (d, J=2.0 Hz, 1H), 7.91 (d, J=2.0 Hz, 1H), 5.13 (q, J=6.4 Hz, 1H), 3.89-3.82 (m, 2H), 3.79 (t, J=5.2 Hz, 2H), 3.58-3.50 (m, 4H), 3.48-3.41 (m, 1H), 3.30-3.26 (m, 1H), 2.46-2.35 (m, 2H), 1.83-1.73 (m, 2H), 1.47 (d, J=6.4 Hz, 3H).
LCMS (ESI) calcd for C23H24ClF3N6O3 [M+H]+ m/z 525.16, found 525.30
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.90 (s, 1H), 8.73 (s, 2H), 8.67 (s, 1H), 8.13 (d, J=2.0 Hz, 1H), 7.91 (d, J=2.0 Hz, 1H), 5.13 (q, J=6.4 Hz, 1H), 3.89-3.82 (m, 2H), 3.79 (t, J=5.2 Hz, 2H), 3.58-3.50 (m, 4H), 3.48-3.41 (m, 1H), 3.30-3.26 (m, 1H), 2.46-2.35 (m, 2H), 1.83-1.73 (m, 2H), 1.47 (d, J=6.4 Hz, 3H).
LCMS (ESI) calcd for C23H24ClF3N6O3 [M+H]+ m/z 525.16, found 525.30
To a solution of 5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 1908 (1 g, 0.0031 mol) was added t-BuOK (1.04 g, 0.0093 mmol) and ethyl 2-bromopropanoate 2302 (2.24 g, 0.0124 mol) at 0° C. The reaction mixture was stirred at rt for 6 h. The reaction solution was quenched with cold water and extracted with EtOAc (20 mL×3). The organic phase was concentrated under reduced pressure and purified by silica gel column (eluting with PE/EtOAc=100:0 to 50:50) to obtain ethyl 2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propanoate 2303 (1 g, 90% purity, 68% yield) as a white solid.
LCMS (ESI) calcd for C19H19F3N4O4[M+H]+ m/z 425.14, found 425.15.
To a solution of ethyl 2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propanoate 2303 (1 g, 0.00235 mol) in EtOH (30 mL) were added LiCl (0.394 g, 0.0094 mol) and NaBH4 (0.355 g, 0.0094 mmol) at rt. The reaction mixture was stirred at rt for 1 h. The resulting mixture was quenched with water and extracted with EtOAc (50 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=100:0 to 50:50) to obtain 1-(1-hydroxypropan-2-yl)-5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2304 (0.8 g, 90% purity, 56% yield) as a white solid.
LCMS (ESI) calcd for C17H17F3N4O3[M+H]+ m/z 383.13, found 383.15.
To a solution of 1-(1-hydroxypropan-2-yl)-5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2304 (139 mg, 0.3626 mmol), 1-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-2-yn-1-one (101 mg, 0.356 mmol) in DCM (15 mL) was added P(n-Bu)3 (37 mg, 0.183 mmol) at rt. The reaction mixture was stirred at rt for 1 h. The resulting mixture was quenched with water and extracted with DCM (50 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=100:0 to 0:100) to obtain (E)-5-(4-methoxybenzyl)-1-(1-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)propan-2-yl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2305 (200 mg, 90% purity, 74% yield) as a white solid.
LCMS (ESI) calcd for C29H28F6N8O4[M+H]+ m/z 667.21, found 667.25.
To a solution of (E)-5-(4-methoxybenzyl)-1-(1-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)propan-2-yl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2305 (200 mg, 0.300 mmol) in MeOH (10 mL) was added 10% Pd/C (20 mg). The mixture was evacuated and backfilled with hydrogen three times and then charged with hydrogen. The resulting mixture was stirred at room temperature for 2 hours. Then the mixture was filtered through celite and concentrated under vacuum to give crude 5-(4-methoxybenzyl)-1-(1-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)propan-2-yl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2306 (190 mg, 90% purity, 85% yield) which was used directly in next step without further purification.
LCMS (ESI) calcd for C29H30F6N8O4[M+H]+ m/z 669.23, found 669.25.
To a solution of 5-(4-methoxybenzyl)-1-(1-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)propan-2-yl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2306 (190 mg, 0.284 mmol) in TFA (8 mL) was added TfOH (0.3 mL) at rt. The reaction solution was stirred at rt for 0.5 h. The mixture was adjusted to pH=8-9 with saturated aqueous NaHCO3 at 0° C. The aqueous layer was extracted with EtOAc (50 mL×3). The combined organic layers were concentrated under reduced pressure. The residue was purified by C18 column, (mobile phase: ACN-H2O (0.1% FA), gradient: 10%-95%) to give 1-(1-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)propan-2-yl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one (mixture of 176 and 177) (90 mg) as a white solid.
Chiral resolution of 1-(1-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)propan-2-yl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one (176 and 177)
Compounds 176 and 177 were separated by SFC (Column: DAICEL AD-H 4.6 mmI.D.*250 mmL 5 um; Mobile phase CO2/MEOH (0.1% FA)=65/35) and concentrated under reduced pressure to afford the first fraction as 176 (31.6 mg, 95% purity, 100% ee, white solid) and the second fraction as 177 (27.5 mg, 100% purity, 100% ee, white solid).
1H NMR (400 MHz, DMSO-d6, ppm) δ:12.84 (s, 1H), 8.73 (s, 2H), 8.65 (s, 1H), 5.23-5.10 (m, 1H), 3.78-3.72 (m, 5H), 3.71-3.63 (m, 2H), 3.52 (m, 1H), 3.49-3.40 (m, 4H), 2.47-2.40 (m, 2H), 1.50 (d, J=6.8 Hz, 3H).
LCMS (ESI) calcd for C21H22F6N8O3[M+H]+ m/z 549.17, found 549.25.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.84 (s, 1H), 8.73 (s, 2H), 8.65 (s, 1H), 8.49 (s, 0.2H), 5.23-5.10 (m, 1H), 3.78-3.72 (m, 5H), 3.71-3.63 (m, 2H), 3.52 (m, 1H), 3.49-3.40 (m, 4H), 2.47-2.40 (m, 2H), 1.50 (d, J=6.8 Hz, 3H).
LCMS (ESI) calcd for C21H22F6N8O3[M+H]+ m/z 549.17, found 549.30.
To a solution of (tert-butoxycarbonyl)proline 2401 (74.0 g, 0.34 mol) in DMF (444 mL) at 0° C. were added K2CO3 (165 g, 1.20 mol) and MeI (97 g, 0.68 mol). The reaction mixture was stirred at rt for 18 h. The reaction solution was quenched with water and extracted with EtOAc (300 mL×3). The organic phase was concentrated and purified by silica gel column to obtain 1-(tert-butyl) 2-methyl pyrrolidine-1,2-dicarboxylate 2402 (65 g, 90% purity, 74% yield) as yellow oil.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 4.23-4.09 (m, 1H), 3.68-3.60 (m, 3H), 3.38-3.31 (m, 2H), 2.27-2.11 (m, 1H), 1.88-1.74 (m, 3H), 1.42-1.28 (m, 9H).
To a solution of 1-(tert-butyl) 2-methyl pyrrolidine-1,2-dicarboxylate 2402 (32.0 g, 0.139 mol) in CCl4 (8 L) was added NBS (86.6 g, 0.486 mol). The reaction mixture was stirred at 85° C. for 1 h. The reaction solution was filtered and concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=90:10) to obtain 1-(tert-butyl) 2-methyl 3-bromo-1H-pyrrole-1,2-dicarboxylate 2403 (22.8 g, 95% purity, 51% yield) as yellow oil.
LCMS (ESI) calcd for C11H14BrNO4 [M−55]+ m/z 248.01, found 248.0
To a solution of 1-(tert-butyl) 2-methyl 3-bromo-1H-pyrrole-1,2-dicarboxylate 2403 (4.2 g, 0.014 mol) in 1,4-Dioxane/H2O=5:1 (182 mL) at room temperature were added 4,4,5,5-tetramethyl-2-vinyl-1,3,2-dioxaborolane 2404 (5.31 g, 0.035 mol), K2CO3 (3.81 g, 0.028 mol) and Pd(dppf)Cl2 (1.01 g, 0.0014 mol). The reaction mixture was stirred at 100° C. for 3 h under N2. After cooling to rt, the reaction solution was quenched with water and extracted with EtOAc (100 mL×3). The organic phase was concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=90:10 to 60:40) to obtain 1-(tert-butyl) 2-methyl 3-vinyl-1H-pyrrole-1,2-dicarboxylate 2405 (1.96 g, 80% purity, 45% yield) as yellow solid.
LCMS (ESI) calcd for C13H17NO4 [M−55]+ m/z 196.12, found 195.95.
To a solution of 1-(tert-butyl) 2-methyl 3-vinyl-1H-pyrrole-1,2-dicarboxylate 2405 (7.4 g, 0.03 mol) in MeOH/H2O=3:1 (400 mL) at 0° C. was added K2OsO4·2H2O (1.08 g, 0.003 mol) and NaIO4 (25.08 g, 0.12 mol). The reaction mixture was stirred at rt for 1 h. The reaction solution was quenched with water and extracted with EtOAc (50 mL×3). The organic phase was concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=90:10 to 0:100) to obtain 1-(tert-butyl) 2-methyl 3-formyl-1H-pyrrole-1,2-dicarboxylate 2406 (3.5 g, 95% purity, 44% yield) as yellow oil.
LCMS (ESI) calcd for C12H15NO5 [M−99]+ m/z 154.10, found 154.15.
To a solution of 1-(tert-butyl) 2-methyl 3-formyl-1H-pyrrole-1,2-dicarboxylate 2406 (4.3 g, 0.017 mol) in DCM (100 mL) at room temperature was added ZnBr2 (7.65 g, 0.034 mol). The reaction mixture was stirred at rt for 18 h under N2. The reaction solution was quenched with water and extracted with EtOAc (50 mL×3). The organic phase was concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=90:10 to 60:40) to obtain methyl 3-formyl-1H-pyrrole-2-carboxylate 2407 (1.2 g, 90% purity, 24% yield) as yellow oil.
LCMS (ESI) calcd for C7H7NO3 [M+H]+ m/z 154.04, found 154.10.
To a solution of methyl 3-formyl-1H-pyrrole-2-carboxylate 2407 (320 mg, 2.1 mmol) in THE (12 mL) was added NBS (409 mg, 2.3 mmol) in portions at 0° C. The reaction was stirred at 0° C. for 2 h. Water was added to quench the reaction. The obtained solution was extracted with EtOAc (50 mL×3). The combined organic phase was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 85:15) to give methyl 4-bromo-3-formyl-1H-pyrrole-2-carboxylate 2408 (260 mg, 90% purity, 48% yield) as a white solid.
LCMS (ESI) calcd for C7H6BrNO3 [M+H]+ m/z 231.95, found 232.00.
To a solution of methyl 4-bromo-3-formyl-1H-pyrrole-2-carboxylate 2408 (310 mg, 1.34 mmol) in AcOH (2 mL) at room temperature was added (4-methoxybenzyl)hydrazine hydrochloride 2409 (504 mg, 2.67 mmol). The reaction mixture was stirred at 80° C. for 18 h. The reaction solution was quenched with water and extracted with EtOAc (50 mL×3). The organic phase was concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=90:10 to 60:40) to obtain 3-bromo-6-(4-methoxybenzyl)-1,6-dihydro-7H-pyrrolo[2,3-d]pyridazin-7-one 2410 (125 mg, 90% purity, 25% yield) as yellow solid.
LCMS (ESI) calcd for C14H12BrN3O2 [M+H]+ m/z 334.01 found 334.10.
To a solution of 3-bromo-6-(4-methoxybenzyl)-1,6-dihydro-7H-pyrrolo[2,3-d]pyridazin-7-one 2410 (445 mg, 1.33 mmol) in THE (10 mL) at 0° C. was added NaH (60%, 266 mg, 6.66 mmol). The reaction mixture was stirred at 0° C. for 10 min with N2. Then added iodoethane (2076 mg, 13.00 mmol). The reaction mixture was stirred at 70° C. for 5 h with N. After cooling to rt, the reaction solution was quenched with ice water and extracted with EtOAc (50 mL×3). The organic phase was concentrated and purified by silica gel column to obtain 3-bromo-1-ethyl-6-(4-methoxybenzyl)-1,6-dihydro-7H-pyrrolo[2,3-d]pyridazin-7-one 2411 (410 mg, 1.02 mmol, 76% yield) as yellow oil.
LCMS (ESI) calcd for C16H16BrN3O2[M+H]+ m/z 362.04, found 362.00.
To a solution of 3-bromo-1-ethyl-6-(4-methoxybenzyl)-1,6-dihydro-7H-pyrrolo[2,3-d]pyridazin-7-one 2411 (300 mg, 0.83 mmol) in ACN (15 mL) at room temperature were added allyltributylstannane 2412 (822 mg, 2.48 mmol) and Pd(AMPHOS)Cl2 (117 mg, 0.17 mmol). The reaction mixture was stirred at 100° C. for 3 h under N2 in a sealed tube. After cooling to rt, the resulting reaction mixture was poured into cold saturated aqueous NH4Cl and stirred for 5 min. Then the mixture was extracted with EtOAc (20 mL×3). The combined organic layer was washed with brine (10 mL×3), dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash silica chromatography (eluting with PE/EtOAc=100:0 to 55:45) to give 3-allyl-1-ethyl-6-(4-methoxybenzyl)-1,6-dihydro-7H-pyrrolo[2,3-d]pyridazin-7-one 2413 (300 mg, 70% purity, 78% yield) as a yellow oil.
LCMS (ESI) calcd for C19H21N3O2 [M+H]+ m/z 324.16 found 324.20.
To a solution of 3-allyl-1-ethyl-6-(4-methoxybenzyl)-1,6-dihydro-7H-pyrrolo[2,3-d]pyridazin-7-one 2413 (150 mg, 0.46 mmol) in Dioxane/H2O=3:1 (10 mL) at 0° C. were added NaIO4 (397 mg, 1.85 mmol) and K2OsO4·2H2O (17 mg, 0.046 mmol). The reaction mixture was stirred at 0° C. for 15 min. The reaction mixture was stirred at rt for 2 h. The reaction solution was quenched with water and extracted with EtOAc (20 mL×3). The organic phase was concentrated under reduced pressure to give 2-(1-ethyl-6-(4-methoxybenzyl)-7-oxo-6,7-dihydro-1H-pyrrolo[2,3-d]pyridazin-3-yl)acetaldehyde 2414 (100 mg, 70% purity, 45% yield) as a yellow oil.
LCMS (ESI) calcd for C18H19N3O3 [M+H]+ m/z 326.14 found 326.15.
To a solution of 2-(1-ethyl-6-(4-methoxybenzyl)-7-oxo-6,7-dihydro-1H-pyrrolo[2,3-d]pyridazin-3-yl)acetaldehyde 2414 (100 mg, 0.30 mmol) in MeOH (5 mL) at 0° C. was added NaBH4 (46 mg, 1.23 mmol). The reaction mixture was stirred at 0° C. for 1 h. The reaction solution was quenched with water and extracted with EtOAc (10 mL×3). The organic phase was concentrated under reduced pressure and the residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 70:30) to give 1-ethyl-3-(2-hydroxyethyl)-6-(4-methoxybenzyl)-1,6-dihydro-7H-pyrrolo[2,3-d]pyridazin-7-one 2415 (70 mg, 40% purity, 27% yield) as yellow oil.
LCMS (ESI) calcd for C18H21N3O3 [M+H]+ m/z 328.16 found 328.15.
To a solution of 1-ethyl-3-(2-hydroxyethyl)-6-(4-methoxybenzyl)-1,6-dihydro-7H-pyrrolo[2,3-d]pyridazin-7-one 2415 (70 mg, 0.21 mmol) in DCM (5 mL) at rt were added 1-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-2-yn-1-one (79 mg, 0.28 mmol) and P(n-Bu)3 (22 mg, 0.11 mmol). The reaction mixture was stirred at rt for 1 h. The reaction solution was quenched with water and extracted with DCM (10 mL×3). The organic phase was concentrated under reduced pressure and the residue was purified by flash chromatography (eluting with DCM/MeOH=100:0 to 95:5) to give (E)-1-ethyl-6-(4-methoxybenzyl)-3-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-1,6-dihydro-7H-pyrrolo[2,3-d]pyridazin-7-one 2416 (70 mg, 50% purity, 26% yield) as yellow oil.
LCMS (ESI) calcd for C30H32F3N7O4[M+H]+ m/z 612.25 found 612.20.
To a solution of (E)-1-ethyl-6-(4-methoxybenzyl)-3-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-1,6-dihydro-7H-pyrrolo[2,3-d]pyridazin-7-one 2416 (70 mg, 0.057 mmol) in MeOH (10 mL) at rt was added Pd/C (24 mg). The reaction mixture was stirred at rt for 24 h under H2. The reaction solution was filtered and washed with MeOH (10 mL×3). The filtrate was concentrated under reduced pressure and the residue was purified by flash chromatography (eluting with DCM/MeOH=100:0 to 95:5) to give 1-ethyl-6-(4-methoxybenzyl)-3-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-1,6-dihydro-7H-pyrrolo[2,3-d]pyridazin-7-one 2417 (30 mg, 70% purity, 29% yield) as yellow oil.
LCMS (ESI) calcd for C30H34F3N7O4[M+H]+ m/z 614.26 found 614.20.
To a solution of 1-ethyl-6-(4-methoxybenzyl)-3-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-1,6-dihydro-7H-pyrrolo[2,3-d]pyridazin-7-one 2417 (30 mg, 0.04 mmol) in TFA (3 mL) at rt was added TfOH (30 mg, 0.20 mmol). The reaction mixture was stirred at rt for 1 h. The reaction solution was quenched with water and adjusted PH 7˜8 with aq. Na2CO3 at 0° C. The water phase was concentrated and purified on a Biotage Isolera One (C18 column, eluting with 20% to 50% MeCN/H2O containing 0.1% formic acid) and prep-TLC (DCM/MeOH=25:1) to give 1-ethyl-3-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-1,6-dihydro-7H-pyrrolo[2,3-d]pyridazin-7-one 203 (2.8 mg, 93% purity, 13% yield) as a yellow solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.24 (s, 1H), 8.73 (s, 2H), 8.19 (s, 1H), 7.37 (s, 1H), 4.44 (q, J=7.2 Hz, 2H), 3.80 (d, J=14.0 Hz, 4H), 3.68 (t, J=6.6 Hz, 2H), 3.61 (t, J=6.8 Hz, 2H), 3.58-3.52 (m, 4H), 2.85 (t, J=6.6 Hz, 2H), 2.63 (t, J=6.4 Hz, 2H), 1.34 (t, J=7.0 Hz, 3H).
LCMS (ESI) calcd for C22H26F3N7O3[M+H]+ m/z 494.20, found 494.25.
Tert-butyl piperazine-1-carboxylate 2502 (5.54 g, 0.030 mol) was added to a solution of 5-fluorobenzo[d]oxazole-2(3H)-thione 2501 (2.5 g, 0.015 mol) in xylene (50 mL). The reaction mixture was stirred at 140° C. for 2 h and then concentrated under reduced pressure. The residue was purified by flash silica chromatography (eluting with EtOAc/PE, 0 to 37%) to give tert-butyl 4-(5-fluorobenzo[d]oxazol-2-yl)piperazine-1-carboxylate 2503 (4.42 g, 90% purity, 83% yield) as a white solid.
LCMS (ESI) calcd for C16H20FN3O3[M+H]+ m/z 322.16, found 322.20.
HCl-Dioxane (4 mol/L, 50 mL) was added to a round-bottom flask containing tert-butyl 4-(5-fluorobenzo[d]oxazol-2-yl)piperazine-1-carboxylate 2503 (4.42 g, 0.013 mol). The reaction mixture was stirred at rt for 20 min and then concentrated under reduced pressure. The residue was triturated with DCM (30 mL). The precipitate was collected and dried in vacuo to give 5-fluoro-2-(piperazin-1-yl)benzo[d]oxazole hydrochloride 2504 (3.41 g, 90% purity, 86% yield) as a white solid.
LCMS (ESI) calcd for C11H12FN3O [M+H]+ m/z 222.10, found 222.20.
DIPEA (147 mg, 1.135 mmol), 5-fluoro-2-(piperazin-1-yl)benzo[d]oxazole hydrochloride 2504 (70 mg, 0.272 mmol) and T3P (289 mg, 0.454 mmol, 50% in EtOAc) were added to a solution of 3-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy)propanoic acid 2505 (100 mg, 0.227 mmol) in DCM (10 mL). The mixture was stirred at rt for 30 min, washed with water (20 mL) and extracted with DCM (10 mL×3). The combined organic layers were washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash silica chromatography (eluting with EtOAc/PE, 0 to 100%) to give 1-(2-(3-(4-(5-fluorobenzo[d]oxazol-2-yl)piperazin-1-yl)-3-oxopropoxy)ethyl)-5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2506 (150 mg, 90% purity, 92% yield) as a colorless oil.
LCMS (ESI) calcd for C30H29F4N7O5[M+H]+ m/z 644.22, found 644.15.
TfOH (0.2 mL) was added to a solution of 1-(2-(3-(4-(5-fluorobenzo[d]oxazol-2-yl)piperazin-1-yl)-3-oxopropoxy)ethyl)-5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2506 (140 mg, 0.217 mmol) in TFA (5 mL) at rt. The mixture was stirred at rt for 10 min. Then pH of the resulting mixture was adjusted to around 8.0 by progressively adding saturated NaHCO3 solution under 0° C. The resulting mixture was extracted with DCM (20 mL×3). The combined organic layers were washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified on a Biotage Isolera One (C18 column, eluting with 30% to 40% MeCN/H2O containing 0.1% formic acid) to give 1-(2-(3-(4-(5-fluorobenzo[d]oxazol-2-yl)piperazin-1-yl)-3-oxopropoxy)ethyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 215 (54.7 mg, 99% purity, 47% yield) as a white solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.87 (s, 1H), 8.59 (s, 1H), 8.46 (s, 0.2H), 7.44-7.39 (m, 1H), 7.15 (dd, J=9.2, 2.4 Hz, 1H), 6.87-6.81 (m, 1H), 4.70 (t, J=4.8 Hz, 2H), 3.82 (t, J=5.0 Hz, 2H), 3.62 (t, J=6.2 Hz, 2H), 3.58-3.54 (m, 2H), 3.54-3.48 (m, 6H), 2.49-2.47 (m, 2H).
LCMS (ESI) calcd for C22H21F4N7O4[M+H]+ m/z 524.17, found 524.25.
Tributyl(vinyl)stannane (2.73 g, 0.0086 mol) and Pd(AMPHOS)Cl2 (0.15 g, 0.0002 mol) were added to a solution of 5-bromo-2-(4-methoxybenzyl)phthalazin-1(2H)-one 2601 (1.50 g, 0.0043 mol) in MeCN (50 mL). The mixture was heated at reflux for 1 h. After cooling to rt, the mixture was concentrated under reduced pressure and purified by flash silica chromatography (eluting with EtOAc/PE, 0 to 15%) to give 2-(4-methoxybenzyl)-5-vinylphthalazin-1(2H)-one 2602 (1.01 g, 74% purity, 60% yield) as a light yellow solid.
LCMS (ESI) calcd for C18H16N2O2 [M+H]+m/z 293.13, found 293.16
K2OsO4·2H2O (0.13 g, 0.0003 mol) was added to a solution of 2-(4-methoxybenzyl)-5-vinylphthalazin-1(2H)-one 2602 (1.0 g, 0.0034 mol) in MeOH/H2O (3/1, 120 mL) at 0° C. After stirring at 0° C. for 10 min to the mixture was added NaIO4 (2.91 g, 0.0136 mol) and then stirred for 2 h at rt. The mixture was filtered and the filtrate was extracted with EtOAc (30 mL×3). The combined organic layers were washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash silica chromatography (eluting with EtOAc/PE, 0 to 56%) to give 2-(4-methoxybenzyl)-1-oxo-1,2-dihydrophthalazine-5-carbaldehyde 2603 (0.43 g, 90% purity, 38% yield) as a white solid.
LCMS (ESI) calcd for C17H14N2O3 [M+H]+ m/z 295.11, found 295.13
TBAF (0.1 mL, 0.139 mmol, 1 mol/L in THF) and TMSCF3 (297 mg, 2.090 mmol) were added to a solution of 2-(4-methoxybenzyl)-1-oxo-1,2-dihydrophthalazine-5-carbaldehyde 2603 (410 mg, 1.393 mmol) in THE (20 mL). The mixture was stirred at rt for 30 min, acidified with HCl (1 mol/L) at 0° C., and extracted with EtOAc (10 mL×3). The combined organic layers were washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified with flash silica chromatography (eluting with EtOAc/PE, 0 to 19%) to give 2-(4-methoxybenzyl)-5-(2,2,2-trifluoro-1-hydroxyethyl)phthalazin-1(2H)-one 2604 (300 mg, 90% purity, 53% yield) as a white solid.
LCMS (ESI) calcd for C18H15F3N2O3[M+H]+ m/z 365.11, found 365.00
Ag2O (951 mg, 4.106 mmol) and MgSO4 (493 mg, 4.106 mmol) were added to a solution of 2-(4-methoxybenzyl)-5-(2,2,2-trifluoro-1-hydroxyethyl)phthalazin-1(2H)-one 2604 (300 mg, 0.821 mmol) in hexane (40 mL). The mixture was heated at reflux for 1 h, then methyl (E)-4-bromobut-2-enoate 2605 (294 mg, 1.642 mmol) was added. The mixture was heated at reflux for 16 h. After cooling to rt, the mixture was filtered to remove Ag2O and the filtrate was concentrated under reduced pressure. The residue was purified by flash silica chromatography (eluting with EtOAc/PE, 0 to 35%) to give methyl (E)-4-(2,2,2-trifluoro-1-(2-(4-methoxybenzyl)-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)but-2-enoate 2606 (270 mg, 70% purity, 50% yield) as a light yellow oil.
LCMS (ESI) calcd for C23H21F3N2O5[M+Na]+ m/z 485.11, found 485.22
To a solution of methyl (E)-4-(2,2,2-trifluoro-1-(2-(4-methoxybenzyl)-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)but-2-enoate 2606 (260 mg, 0.561 mmol) in MeOH (20 mL) was added Pd/C (10%, 50 mg) at rt. The suspension was degassed with H2 for 6 times. The reaction mixture was stirred at rt for 3 h under H2 atmosphere. The resulting reaction mixture was filtered through celite. The filtrate was concentrated under reduced pressure to obtain methyl 4-(2,2,2-trifluoro-1-(2-(4-methoxybenzyl)-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)butanoate 2607 (240 mg, 59% purity, 54% yield) as a yellow oil.
LCMS (ESI) calcd C23H23F3N2O5[M+H]+ m/z 465.16, found 465.19
LiOH (35 mg, 1.483 mmol) was added to a solution of methyl 4-(2,2,2-trifluoro-1-(2-(4-methoxybenzyl)-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)butanoate 2607 (230 mg, 0.494 mmol) in THF/H2O (3/1, 16 mL). The mixture was stirred at rt for 2 h, concentrated under reduced pressure to remove THF, acidified with HCl solution (1 mol/L) and extracted with DCM (10 mL×3). The combined organic layers were washed with brine, dried over Na2SO4 and concentrated in vacuo to give 4-(2,2,2-trifluoro-1-(2-(4-methoxybenzyl)-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)butanoic acid 2608 (240 mg, 60% purity, 64% yield) as a light yellow oil.
LCMS (ESI) calcd for C22H21F3N2O5[M+H]+ m/z 451.15, found 451.15
DIPEA (329 mg, 2.547 mmol), 2-(piperazin-1-yl)-5-(trifluoromethyl)pyrimidine hydrochloride (164 mg, 0.611 mmol) and T3P (648 mg, 1.019 mmol, 50% in EtOAc) were added to a solution of 4-(2,2,2-trifluoro-1-(2-(4-methoxybenzyl)-1-oxo-1,2-dihydrophthalazin-5-yl)ethoxy)butanoic acid 2608 (230 mg, 0.509 mmol) in DCM (10 mL). The mixture was stirred at rt for 30 min, diluted with water (20 mL) and extracted with DCM (20 mL×3). The combined organic layers were washed with brine, dried over Na2SO4 and concentrated under reduced pressure to give 2-(4-methoxybenzyl)-5-(2,2,2-trifluoro-1-(4-oxo-4-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)butoxy)ethyl)phthalazin-1(2)-one 2609 (300 mg, 70% purity, 62% yield) as a light yellow oil.
LCMS (ESI) calcd for C31H30F6N6O4[M+H]+ m/z 665.23, found 665.15
TfOH (0.2 mL) was added to a solution of 2-(4-methoxybenzyl)-5-(2,2,2-trifluoro-1-(4-oxo-4-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)butoxy)ethyl)phthalazin-1(2H)-one 2609 (300 mg, 0.451 mmol) in TFA (10 mL). The reaction mixture was stirred at rt for 10 min, adjusted to pH=8 by progressively adding saturated NaHCO3 solution then extracted with DCM (20 mL×3). The combined organic layers were washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified with C18 column (Agela 40 g, mobile phase: MeCN—H2O (0.1% FA), gradient: 40%-50%) to give 5-(2,2,2-trifluoro-1-(4-oxo-4-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)butoxy)ethyl)phthalazin-1(2H)-one 221 and 222 (93 mg, 99%, 37% yield) as a white solid.
Compounds 221 and 222 were separated by SFC (Column: Daicel CHIRALPAK IC 250 mm×20 mm I.D., 5 m; Mobile phase: CO2/MeOH (0.1% NH3)=65/35) and concentrated under reduced pressure to afford the first fraction as 221 (24.7 mg, 99% purity, 100% ee, white solid) and the second fraction as 222 (32.7 mg, 99% purity, 100% ee, white solid).
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.85 (s, 1H), 8.77 (s, 1H), 8.74 (s, 2H), 8.35 (d, J=8.0 Hz, 1H), 8.10 (d, J=7.6 Hz, 1H), 7.95 (t, J=7.8 Hz, 1H), 6.04-5.95 (m, 1H), 3.86-3.81 (m, 2H), 3.80-3.74 (m, 2H), 3.72-3.65 (m, 1H), 3.58-3.48 (m, 5H), 2.46-2.35 (m, 2H), 1.88-1.79 (m, 2H).
LCMS (ESI) calcd for C23H22F6N6O3[M+H]+ m/z 545.17, found 545.15
1H NMR (400 MHz, DMSO-d6, ppm) δ. 12.85 (s, 1H), 8.77 (s, 1H), 8.74 (s, 2H), 8.35 (d, J=8.0 Hz, 1H), 8.10 (d, J=7.6 Hz, 1H), 7.95 (t, J=7.8 Hz, 1H), 6.05-5.97 (m, 1H), 3.86-3.80 (m, 2H), 3.80-3.75 (m, 2H), 3.72-3.65 (m, 1H), 3.59-3.48 (m, 5H), 2.46-2.35 (m, 2H), 1.89-1.79 (m, 2H).
LCMS (ESI) calcd for C23H22F6N6O3[M+H]+ m/z 545.17, found 545.10
To a stirred solution of NaH (60% wt, 5.95 g, 148.8 mmol) in THF (400 mL) at 0° C. was added ethyl 2-methyl-1H-pyrrole-3-carboxylate 2701 (4.06 g, 26.5 mmol) in portions. After stirring 15 min at 0° C., ethyl 2-bromopropanoate 2702 (24.4 g, 134.8 mmol) was added dropwise and the reaction was warmed to rt and stirred for 16 h. The reaction was quenched with saturated aqueous NH4Cl and extracted with EtOAc (200 mL×4). The combined organic layers were washed with brine (30 mL), dried over Na2SO4 and concentrated in vacuo. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 95:5) to afford ethyl 1-(1-ethoxy-1-oxopropan-2-yl)-2-methyl-1H-pyrrole-3-carboxylate 2703 (7.38 g, 98% purity, 72% yield) as an off-white solid.
LCMS (ESI) calcd for C13H19NO4 [M+H]+ m/z 254.13, found 254.10.
Ethyl 1-(1-ethoxy-1-oxopropan-2-yl)-2-methyl-1H-pyrrole-3-carboxylate 2703 (7.38 g, 28.88 mmol) was dissolved in THE (885 mL) under stirring, followed by addition a solution of AcOH (148 mL) and H2O (148 mL). The mixture was homogeneously stirred at 0° C. and then CAN (94.4 g, 172.5 mmol) was added in one portion. After stirring at rt for 1 h, the reaction mixture was poured into ice-water (2000 mL) and stirred for another 30 min. The resulting solution was extracted with EtOAc (500 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 90:10) to obtain the title compound ethyl 1-(1-ethoxy-1-oxopropan-2-yl)-2-formyl-1H-pyrrole-3-carboxylate 2704 (9.09 g, 90% purity, 86% yield) as a white solid.
LCMS (ESI) calcd for C13H17NO5 [M+H]+ m/z 268.11, found 268.15.
To a solution of ethyl 1-(1-ethoxy-1-oxopropan-2-yl)-2-formyl-1H-pyrrole-3-carboxylate 2704 (9.09 g, 33.9 mmol) in ACN (500 mL) was added NBS (5.8 g, 32.5 mmol) in one portion. The reaction mixture was stirred at rt for 1 h. The resulting mixture was diluted with water and extracted with DCM (30 mL×3). The combined organic layer was dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 70:30) to obtain ethyl 4-bromo-1-(1-ethoxy-1-oxopropan-2-yl)-2-formyl-1H-pyrrole-3-carboxylate 2705 (3.23 g, 90% purity, 26% yield) as a white solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ 10.01 (s, 1H), 7.74 (s, 1H), 5.63 (q, J=7.2 Hz, 1H), 4.33 (q, J=7.2 Hz, 2H), 4.15-4.10 (m, 2H), 1.67 (d, J=7.6 Hz, 3H), 1.32 (t, J=7.0 Hz, 3H), 1.17 (t, J=7.0 Hz, 3H)
To a solution of ethyl 4-bromo-1-(1-ethoxy-1-oxopropan-2-yl)-2-formyl-1H-pyrrole-3-carboxylate 2705 (3.23 g, 9.37 mmol) in AcOH (50 mL) was added H2NNH2·H2O (80% wt, 630 mg, 15.75 mmol) in one portion. The reaction mixture was heated with stirring at 80° C. for 2 h. The solvent was removed by evaporation (55° C.) under reduced pressure. The residue was diluted with DCM (50 mL) and then adjusted to pH to 8 with saturated aqueous NaHCO3 at 0° C. The basified solution was extracted with DCM (10 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure to obtain ethyl 2-(3-bromo-4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 2706 (2.06 g, 95% purity, 67% yield) as a white solid.
LCMS (ESI) calcd for C11H12BrN3O3 [M+H]+ m/z 314.01, found 314.05
To a solution of ethyl 2-(3-bromo-4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 2706 (2.06 g, 6.6 mmol) and DIPEA (4.3 g, 33.3 mmol) in DMF (100 mL) at rt, SEMCl (5.40 g, 32.5 mmol) was added. After completing of addition, the reaction solution was heated at 80° C. for 1 h. The resulting reaction solution was cooled and poured into cold water, and then extracted with EtOAc (200 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=70:30 to 40:60) to give ethyl 2-(3-bromo-4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 2707 (3 g, 90% purity, 89% yield) as a white solid.
LCMS (ESI) calcd for C17H26BrN3O4Si [M+H]+ m/z 444.09, found 444.05.
A solution of ethyl 2-(3-bromo-4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 2707 (2.24 g, 5.0 mmol) and methyl 2,2-difluoro-2-(fluorosulfonyl)acetate 2708 (4.86 g, 25.2 mmol), CuI (1.92 g, 10.1 mmol) and HMPA (4.51 g, 25.2 mmol) in NMP (30 mL) was prepared at rt. The mixture was heated at 170° C. in a microwave reactor for 1.5 hours under an atmosphere of N2. The resulting reaction solution was poured into cold water and then extracted with EtOAc (200 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with EtOAc/PE=0%-30%) to give ethyl 2-(4-oxo-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 2709 (0.665 g, 65% purity, 33% yield) as a yellow solid.
LCMS (ESI) calcd for C18H26F3N3O4Si [M+H]+ m/z 434.16, found 434.10.
To a suspension of ethyl 2-(4-oxo-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 2709 (665 mg, 1.53 mmol) and LiCl (265 mg, 6.25 mmol) in MeOH (20 mL) was added NaBH4 (243 mg, 6.42 mmol) at 0° C. Then the reaction mixture was stirred at rt for 2 h. The resulting mixture was quenched with saturated aqueous NH4Cl and then extracted with EtOAc. The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with DCM/MeOH=100:0 to 90:10) to obtain 1-(1-hydroxypropan-2-yl)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 2710 (365 mg, 65% purity, 73% yield) as a yellow oil.
LCMS (ESI) calcd for C16H24F3N3O3Si [M+H]+ m/z 392.15, found 392.17.
A round-bottom flask containing a mixture of 1-(1-hydroxypropan-2-yl)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 2710 (130 mg, 0.332 mmol), 1-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-2-yn-1-one (124 mg, 0.437 mmol) and P(n-Bu)3 (68 mg, 0.337 mmol) in DCM (20 mL) was stirred at rt for 16 h. The resulting reaction solution was concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with DCM/MeOH=90:10) to give of (E)-1-(1-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)propan-2-yl)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 2711 (156 mg, 70% purity, 69% yield) as a yellow solid.
LCMS (ESI) calcd for C28H35F6N7O4Si [M+H]+ m/z 676.24, found 676.20.
A mixture of compound (E)-1-(1-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)propan-2-yl)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 2711 (156 mg, 0.231 mmol) and Pd(OH)2 (150 mg) in MeOH (20 mL) was stirred at rt under H2 atmosphere for 16 hours. The resulting mixture was filtered through diatomaceous earth. The filtrate was concentrated to dryness under reduced pressure. The residue was purified by flash chromatography (eluting with DCM/MeOH=98:2) to 1-(1-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)propan-2-yl)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 2712 (83 mg, 80% purity, 70% yield) as a white solid.
LCMS (ESI) calcd for C28H37F6N7O4Si [M+H]+ m/z 678.26, found 678.30.
A round-bottom flask containing a mixture of 1-(1-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)propan-2-yl)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 2712 (83 mg, 0.123 mmol), HCl in 1,4-dioxane (4 M, 15 mL) was stirred at rt for 12 h. The resulting mixture was concentrated to dryness under reduced pressure. The mixture was adjusted to pH 8-9 with saturated aq. NaHCO3, and then extracted with EtOAc (50 mL×3). The combined organic layers were concentrated under reduced pressure. The residue was purified by C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 10%-95%) to give 1-(1-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)propan-2-yl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 223 and 224 (54 mg, 88% purity, 77% yield) as a white solid.
LCMS (ESI) calcd for C22H23F6N7O3[M+H]+ m/z 548.18, found 548.27.
Compounds 223 and 224 were separated by SFC (Column: DAICEL AD-H 4.6 mm I.D.×250 mmL 5 um; Mobile phase: CO2/MeOH (0.1% NH3)=70/30) and concentrated under reduced pressure to afford the first fraction as 223 (14.0 mg, 99% purity, 100% ee, off-white solid) and the second fraction as 224 (15.2 mg, 99% purity, 93% ee, white solid).
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.55 (s, 1H), 8.73 (s, 2H), 8.49 (s, 1H), 8.14 (s, 1H), 4.99-4.88 (m, 1H), 3.82-3.70 (m, 6H), 3.70-3.54 (m, 2H), 3.52-3.42 (m, 4H), 2.49-2.45 (m, 2H), 1.46 (d, J=6.8 Hz, 3H).
LCMS (ESI) calcd for C22H23F6N7O3 [M+H]+ m/z 548.18, found 548.15.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.55 (s, 1H), 8.73 (s, 2H), 8.49 (s, 1H), 8.14 (s, 1H), 5.00-4.87 (m, 1H), 3.81-3.70 (m, 6H), 3.70-3.54 (m, 2H), 3.52-3.42 (m, 4H), 1.46 (d, J=7.2 Hz, 3H).
LCMS (ESI) calcd for C22H23F6N7O3 [M+H]+ m/z 548.18, found 548.15.
Ethyl 2-chloro-4,4,4-trifluoro-3-oxobutanoate 2801 (2180 mg, 10 mmol) was combined with formamide (4492 mg, 100 mmol) and water (0.4 mL). The reaction was heated at 130° C. for 1.5 h. The mixture was then cooled to rt, and 8 mL of ice water was added. The resulting solids were collected and washed with water then dried in vacuo to give ethyl 4-(trifluoromethyl)-1H-imidazole-5-carboxylate 2802 (440 mg, 90% purity, 19% yield) as a brown solid.
LCMS (ESI) calcd for C7H7F3N2O2 [M+H]+ m/z 209.05, found 209.10
To a solution of ethyl 4-(trifluoromethyl)-1H-imidazole-5-carboxylate 2802 (1500 mg, 7.2 mmol) in CH3CN (15 mL) was added NBS (1530 mg, 8.4 mmol). The mixture was stirred at 85° C. for 2 h. Water was added to quench the reaction. The obtained solution was extracted with EtOAc (40 mL×4). The combined organic phase was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 95:5) to give ethyl 2-bromo-4-(trifluoromethyl)-1H-imidazole-5-carboxylate 2803 (1560 mg, 90% purity, 67% yield) as a white solid.
LCMS (ESI) calcd for C7H6BrF3N2O2 [M+H]+ m/z 286.95, found 287.00
To a solution of NaH (60%, 600 mg, 15 mmol) in DMF (5 mL) was added dropwise a solution of ethyl 2-bromo-4-(trifluoromethyl)-1H-imidazole-5-carboxylate 2803 (1440 mg, 5 mmol) and 2-bromoacetonitrile (600 mg, 5 mmol) in DMF (20 mL) at 0° C. under N2 atmosphere. The reaction mixture was warmed to 70° C. and kept stirring for an additional 2 h. After completion of reaction, the reaction mixture was cooled to rt and then poured into cold saturated aqueous NH4Cl. The resulting solution was extracted with EtOAc (40 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash silica chromatography (eluting with PE/EtOAc=100:0 to 90:10) to give ethyl 2-bromo-1-(cyanomethyl)-4-(trifluoromethyl)-1H-imidazole-5-carboxylate 2804 (1250 mg, 90% purity, 68.8 yield) as a white solid.
LCMS (ESI) calcd for C9H7BrF3N3O2 [M+H]+ m/z 325.97, found 326.05
To a solution of ethyl 2-bromo-3-(cyanomethyl)-5-(trifluoromethyl)imidazole-4-carboxylate 2804 (1280 mg, 4 mmol) in THF (40 mL) was added slowly BH3-THF (1 M, 20 mL, 20 mmol) at 0° C. After completion of addition, the reaction solution was warmed to rt and kept stirring at rt for an additional 5 h. The resulting reaction solution was added dropwise MeOH (15 mL) to quench the BH3-THF at rt (caution: gas released) and then concentrated under reduced pressure to get ethyl 1-(2-aminoethyl)-2-bromo-4-(trifluoromethyl)-1H-imidazole-5-carboxylate (600 mg, 85% purity, 40% yield) as a white oil.
LCMS (ESI) calcd for C9H11BrF3N3O2 [M+H]+ m/z 330.0, found 330.05
Ethyl 1-(2-aminoethyl)-2-bromo-4-(trifluoromethyl)-1H-imidazole-5-carboxylate (1200 mg, 3.6 mmol) was diluted with NH3-MeOH (7 M, 7 mL) and kept stirring at rt overnight. LCMS monitored the formation of product, the reaction mixture was evaporated under reduced pressure to afford 3-bromo-1-(trifluoromethyl)-6,7-dihydroimidazo[1,5-a]pyrazin-8(5H)-one 2805 (700 mg, 75% purity, 51% yield) as an white solid
LCMS (ESI) calcd for C7H5BrF3N3O [M+H]+ m/z 283.96, found 284.00
To a solution of t-BuOK (664 mg, 6 mmol) in DMF (12 mL) was added slowly a solution of 3-bromo-1-(trifluoromethyl)-6,7-dihydroimidazo[1,5-a]pyrazin-8(5H)-one 2805 (560 mg, 2 mmol) and PMBCl (926 mg, 6 mmol) in DMF (8 mL) at 0° C. under N2 atmosphere. After completion of addition, the reaction was warmed to rt and kept stirring at rt for an additional 1.5 h. The resulting reaction mixture was poured into cold saturated aqueous NH4Cl and stirred for 5 min. Then the solution was extracted with EtOAc (50 mL×3). The combined organic layer was washed with brine (50 mL×3), dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash silica chromatography (eluting with PE/EtOAc=100:0 to 55:45) to give 3-bromo-7-(4-methoxybenzyl)-1-(trifluoromethyl)-6,7-dihydroimidazo[1,5-a]pyrazin-8(5H)-one 2806 (600 mg, 90% purity, 67% yield) as a yellow solid.
LCMS (ESI) calcd for C15H13BrF3N3O2 [M+H]+ m/z 404.01, found 404.10
A solution of 3-bromo-7-(4-methoxybenzyl)-1-(trifluoromethyl)-6,7-dihydroimidazo[1,5-a]pyrazin-8(5H)-one 2806 (480 mg, 1.2 mmol), (E)-2-(2-ethoxyvinyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (471 mg, 2.4 mmol), K3PO4 (278 mg, 1.2 mmol) and Pd(dppf)Cl2 (87 mg, 0.12 mmol) in Dioxane/H2O (30 mL, 3:1) was stirred at 80° C. for 4 h under N2 atmosphere. After cooling to rt, the reaction mixture was added into cold water and then extracted with EtOAc (60 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash silica chromatography (eluting with PE/EtOAc=100:0 to 50:50) to give (E)-3-(2-ethoxyvinyl)-7-(4-methoxybenzyl)-1-(trifluoromethyl)-6,7-dihydroimidazo[1,5-a]pyrazin-8(5H)-one 2807 (480 mg, 70% purity, 74% yield) as a colorless oil.
LCMS (ESI) calcd for C19H20F3N3O3[M+H]+ m/z 396.15, found 396.0
To a solution of (E)-3-(2-ethoxyvinyl)-7-(4-methoxybenzyl)-1-(trifluoromethyl)-6,7-dihydroimidazo[1,5-a]pyrazin-8(5H)-one 2807 (390 mg, 1 mmol) in THE (30 mL) was added 2 M aqueous HCl (15 mL) in one portion. The solution was then stirred at 70° C. for 5 h. The resulting reaction solution was basified (pH 8) by saturated aqueous NaHCO3 at 0° C. and then extracted with EtOAc (30 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The crude 2-(7-(4-methoxybenzyl)-8-oxo-1-(trifluoromethyl)-5,6,7,8-tetrahydroimidazo[1,5-a]pyrazin-3-yl)acetaldehyde 2808 (200 mg crude, 80% purity, 44.3% yield) as a brown oil was used directly in next step.
LCMS (ESI) calcd for C17H16F3N3O3[M+H]+ m/z 368.11, found 368.20
To a solution of 2-(7-(4-methoxybenzyl)-8-oxo-1-(trifluoromethyl)-5,6,7,8-tetrahydroimidazo[1,5-a]pyrazin-3-yl)acetaldehyde 2808 (900 mg, 2.5 mmol) in MeOH (10 mL) was added NaBH4 (140 mg, 3.6 mmol) in portions at 0° C. The solution was warmed to rt and stirred for 1 h. Saturated aqueous NH4Cl (15 mL) was added into the reaction solution and then stirred for 5 min. The resulting solution was extracted with EtOAc (50 mL×4). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash silica chromatography (eluting with PE/EtOAc=50:50 to 0:100) to give 3-(2-hydroxyethyl)-7-(4-methoxybenzyl)-1-(trifluoromethyl)-6,7-dihydroimidazo[1,5-a]pyrazin-8(5H)-one 2809 (620 mg, 90% purity, 62% yield) as a yellow solid.
LCMS (ESI) calcd for C17H18F3N3O3[M+H]+ m/z 370.13, found 370.15
To a solution of 3-(2-hydroxyethyl)-7-(4-methoxybenzyl)-1-(trifluoromethyl)-6,7-dihydroimidazo[1,5-a]pyrazin-8(5H)-one 2809 (200 mg, 0.56 mmol) and 1-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-2-yn-1-one (168 mg, 0.60 mmol) in DCM (20 mL) was added P(n-Bu)3 (56 mg, 0.28 mmol) dropwise. After completion of addition, the reaction solution was stirred at rt for 2 h. The resulting solution was evaporated under reduced pressure to get a deep brown solid crude which was purified by flash silica chromatography (eluting with PE/EtOAc=50:50 to 0:100) to give (E)-7-(4-methoxybenzyl)-3-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-1-(trifluoromethyl)-6,7-dihydroimidazo[1,5-a]pyrazin-8(5H)-one 2810 (228 mg, 90% purity, 58% yield) as a yellow solid.
LCMS (ESI) calcd for C29H29F6N7O4[M+Na]+ m/z 676.21, found 676.75
A solution of (E)-7-(4-methoxybenzyl)-3-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-1-(trifluoromethyl)-6,7-dihydroimidazo[1,5-a]pyrazin-8(5H)-one 2810 (280 mg, 0.43 mmol) and Pd/C (46 mg) in MeOH (10 mL) was stirred at rt for 1 h under H2 atmosphere. The resulting solution was filtered through diatomaceous earth and the filter cake was washed with MeOH (10 mL×4). The filtrate was concentrated under reduced pressure to give 2-(4-methoxybenzyl)-6-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one 2811 (99 mg, 90% purity, 32% yield) as a colorless oil, which was used directly in the next step without further purification.
LCMS (ESI) calcd for C29H31F6N7O4 [M+H]+ m/z 656.23, found 656.30
To a solution of 2-(4-methoxybenzyl)-6-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one 2811 (100 mg, 0.15 mmol) in TFA (10 ml) was added TfOH (228 mg, 1.5 mmol) at rt. After completion of addition, the reaction solution was stirred at rt for 3 h. The resulting solution was concentrated under reduced pressure to remove most TFA. The residue was diluted with DCM (20 mL) and then adjusted to pH to 8 with saturated aqueous NaHCO3 at 0° C. The basified solution was extracted with DCM (20 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The crude product was purified by flash silica chromatography (eluting with DCM/MeOH=100:0 to 90:10) and C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 30-60) to give 3-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-1-(trifluoromethyl)-6,7-dihydroimidazo[1,5-a]pyrazin-8(5H)-one (compound 235, 14.6 mg, 100% purity, 17% yield) as a white solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 8.73 (s, 2H), 8.24 (s, 1H), 4.16 (t, J=5.8 Hz, 2H), 3.87-3.75 (m, 4H), 3.71 (t, J=6.4 Hz, 2H), 3.65 (t, J=6.4 Hz, 2H), 3.56-3.48 (m, 6H), 2.96 (t, J=6.4 Hz, 2H), 2.60 (t, J=6.4 Hz, 2H).
LCMS (ESI) calcd for C21H23F6N7O3 [M+H]+ m/z 536.18, found 536.30
To a solution of 5-(dimethylamino)-2-(2-methoxy-5-methylphenyl)-3-oxopyridazine-4-carbaldehyde 1905 (2.6 g, 0.009 mol) in EtOH (50 mL) was added H2NNH2·H2O (80% wt, 2.0 g, 0.050 mol) at rt. The reaction mixture was stirred at 80° C. for 24 h. The resulting mixture was concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=20:80 to 0:100) to afford 5-(4-methoxybenzyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2902 (1.5 g, 90% purity, 59% yield) as a white solid.
LCMS (ESI) calcd for C13H2N4O2 [M+H]+ m/z 257.10, found 257.13.
To a solution of 5-(2-methoxy-5-methylphenyl)-1H-pyrazolo[3,4-d]pyridazin-4-one 2902 (1.13 g, 4.4 mmol) in EtOH/H2O (1:1, 20 mL) was added NaOAc (2.53 g, 30.8 mmol) and Br2 (2.81 g, 17.6 mmol) successively at rt. The reaction mixture was stirred at rt for 1 h. The resulting mixture was quenched with saturated aq. Na2S2O3 and extracted with EtOAc (50 mL×2). The combined organic layers were concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=85:15 to 70:30) to afford 3-bromo-5-(4-methoxybenzyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2903 (1.08 g, 90% purity, 66% yield) as a yellow solid.
LCMS (ESI) calcd for C13H11BrN4O2[M+H]+ m/z 335.01, found 335.10.
To a solution of 3-bromo-5-(4-methoxybenzyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2903 (1.0 g, 3.0 mmol) in DMF (20 mL) was added t-BuOK (1.01 g, 9.0 mmol) at 0° C. The reaction mixture was stirred at 0° C. for 15 min and ethyl 2-bromoacetate 2904 (1.5 g, 9.0 mmol) was added dropwise at 0° C. The reaction solution was stirred at rt for 2 h. The reaction solution was quenched with ice-water and extracted with EtOAc (20 mL×3). The organic phase was concentrated and purified by flash column chromatography (eluting with PE/EtOAc=85:15 to 50:50) to obtain ethyl 2-(3-bromo-5-(4-methoxybenzyl)-4-oxo-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)acetate 2905 (1.3 g, 90% purity, 97% yield) as a white solid.
LCMS (ESI) calcd for C17H17BrN4O4[M+H]+ m/z 421.04, found 421.15.
To a solution of ethyl 2-(3-bromo-5-(4-methoxybenzyl)-4-oxo-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)acetate 2905 (1.35 g, 3.2 mmol) in ACN (30 mL) were added tributyl(vinyl) stannane 2906 (1.52 g, 4.8 mmol) and Pd(AMPHOS)Cl2 (230 mg, 0.3 mmol) at rt. The resulting mixture was stirred at 100° C. for 1 h. After cooling to rt, the mixture was concentrated in vacuo. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 40: 60) to obtain ethyl 2-(5-(4-methoxybenzyl)-4-oxo-3-vinyl-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)acetate 2907 (1.0 g, 90% purity, 75% yield) as a yellow solid.
LCMS (ESI) calcd for C19H20N4O4 [M+H]+ m/z 369.15 found 369.20.
To a solution of ethyl 2-(5-(4-methoxybenzyl)-4-oxo-3-vinyl-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)acetate 2907 (770 mg, 2.09 mmol) in Dioxane/H2O (3:1, 20 mL) were added K2OsO4·2H2O (77 mg, 0.21 mmol) and NaIO4 (1.8 g, 8.36 mol) at rt. The reaction mixture was stirred at rt for 4 h. The resulting mixture was diluted with water and extracted with EtOAc (50 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=100:0 to 50:50) to give ethyl 2-(3-formyl-5-(4-methoxybenzyl)-4-oxo-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)acetate 2908 (520 mg, 90% purity, 60% yield) as a yellow oil.
LCMS (ESI) calcd for C18H18N4O5[M+H]+ m/z 371.13, found 371.20.
To a solution of ethyl 2-(3-formyl-5-(4-methoxybenzyl)-4-oxo-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)acetate 2908 (0.5 g, 1.35 mmol) in DCM (20 mL) was added DAST (1.74 g, 10.8 mmol) dropwise at 0° C. under N2 atmosphere. The reaction solution was stirred at rt for 2 h. The reaction was quenched with aq. NaHCO3, the aqueous layer was extracted with DCM (100 mL×3). The combined organic layers were concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=70:30 to 50:50) to afford ethyl 2-(3-(difluoromethyl)-5-(4-methoxybenzyl)-4-oxo-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)acetate 2909 (420 mg, 90% purity, 71% yield) as a white solid.
LCMS (ESI) calcd for C18H18F2N4O4 [M+H]+ m/z 393.13, found 393.18.
To a solution of ethyl 2-(3-(difluoromethyl)-5-(4-methoxybenzyl)-4-oxo-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)acetate 2909 (320 mg, 0.81 mmol) in EtOH (10 mL) were added LiCl (138 mg, 3.26 mmol) and NaBH4 (123 mg, 3.26 mmol) at rt. The reaction mixture was stirred at rt for 1 h. The resulting mixture was quenched with water and extracted with EtOAc (50 mL×3). The combined organic layers were washed with brine and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluting with EtOAc/PE, 0 to 50%) to obtain 3-(difluoromethyl)-1-(2-hydroxyethyl)-5-(4-methoxybenzyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2910 (270 mg, 80% purity, 75% yield) as white solid.
LCMS (ESI) calcd for C16H16F2N4O3[M+H]+ m/z 351.12, found 351.20
To a solution of 3-(difluoromethyl)-1-(2-hydroxyethyl)-5-(4-methoxybenzyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2910 (150 mg, 0.42 mmol), 1-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-2-yn-1-one (122 mg, 0.42 mmol) in DCM (15 mL) was added P(n-Bu)3 (43 mg, 0.21 mmol) at rt. The reaction mixture was stirred at rt for 1 h. The resulting mixture was quenched with water and extracted with DCM (50 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure. The residue was purified by silica gel column (eluting with EtOAc/PE, 0 to 100%) to obtain (E)-3-(difluoromethyl)-5-(4-methoxybenzyl)-1-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2911 (190 mg, 90% purity, 63% yield) as a white solid.
LCMS (ESI) calcd for C28H27F5N8O4 [M+H]+ m/z 635.21, found 635.40
To a solution of (E)-3-(difluoromethyl)-5-(4-methoxybenzyl)-1-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2911 (100 mg, 0.15 mmol) in MeOH (10 mL) was added 10% Pd/C (10 mg). The mixture was evacuated and backfilled with hydrogen three times and then charged with hydrogen. The resulting mixture was stirred at room temperature for 2 hours under N2. Then the mixture was filtered through celite and concentrated under vacuum to give 3-(difluoromethyl)-5-(4-methoxybenzyl)-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2912 (100 mg, 90% purity, 90% yield) which was used directly in next step without further purification.
LCMS (ESI) calcd for C28H29F5N8O4[M+H]+ m/z 637.22, found 637.35
To a solution of 3-(difluoromethyl)-5-(4-methoxybenzyl)-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2912 (100 mg, 0.15 mmol) in TFA (1 mL) was added TfOH (707 mg, 4.71 mmol) dropwise. The mixture was stirred in rt for 2 h. The resulting light brown solution was concentrated under reduced pressure to remove most TFA. The residue was diluted with DCM (10 mL) and then adjusted pH to 8 with saturated aqueous NaHCO3 at 0° C. The basified solution was extracted with DCM (10 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The crude product was purified by C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 30%-60%) to give 3-(difluoromethyl)-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 236 (39.4 mg, 100% purity, 48% yield) as a white solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ:12.75 (s, 1H), 8.73 (s, 2H), 8.55 (s, 1H), 7.30 (t, J=53.2 Hz, 1H), 4.66 (t, J=5.0 Hz, 2H), 3.87-3.73 (m, 6H), 3.63 (t, J=6.4 Hz, 2H), 3.52-3.42 (m, 4H), 2.49-2.46 (m, 2H).
LCMS (ESI) calcd for C20H21F5N8O3[M+H]+ m/z 517.17, found 517.29
To a solution of 4,5-dichloropyridazin-3(2H)-one 1901 (10 g, 0.061 mol) in DMF (100 mL) at 0° C. were added BOMCl (11.39 g, 0.073 mol) and DBU (11.07 g, 0.073 mol). The reaction mixture was stirred at rt for 2 h. The reaction solution was quenched with water and extracted with EtOAc (50 mL×3). The organic phase was concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=100:0 to 95:5) to obtain 2-((benzyloxy)methyl)-4,5-dichloropyridazin-3(2H)-one 3002 (13.5 g, 90% purity, 70% yield) as a white solid.
LCMS (ESI) calcd for C12H10Cl2N2O2 [M+H]+ m/z 285.01, found 284.95.
To a solution of 2-((benzyloxy)methyl)-4,5-dichloropyridazin-3(2H)-one 3002 (13.5 g, 0.047 mol) in DMF (230 mL) at room temperature were added ethyl 2-aminoacetate HCl salt 3003 (5.37 g, 0.052 mol) and DIPEA (18.34 g, 0.14 mol). The reaction mixture was stirred at 100° C. for 3 h. The reaction solution was quenched with water and extracted with EtOAc (300 mL×3). The organic phase was concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=100:0 to 70:30) to obtain ethyl (1-((benzyloxy)methyl)-5-chloro-6-oxo-1,6-dihydropyridazin-4-yl)glycinate 3004 (15 g, 90% purity, 81% yield) as yellow solid.
LCMS (ESI) calcd for C16H1sClN3O4[M+H]+ m/z 352.10, found 352.05.
To a solution of ethyl (1-((benzyloxy)methyl)-5-chloro-6-oxo-1,6-dihydropyridazin-4-yl)glycinate 3004 (4.2 g, 0.012 mol) in EtOH (300 mL) at 0° C. was added NaBH4 (1.80 g, 0.048 mol) and LiCl (2.02 g, 0.048 mol). The reaction mixture was stirred at rt for 1 h. The reaction solution was quenched with water and extracted with EtOAc (50 mL×3). The organic phase was concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=100:0 to 0:100) to obtain 2-((benzyloxy)methyl)-4-chloro-5-((2-hydroxyethyl)amino)pyridazin-3(2H)-one 3005 (3.4 g, 90% purity, 83% yield) as yellow solid.
LCMS (ESI) calcd for C14H16ClN3O3[M+H]+ m/z 310.09, found 310.00.
To a solution of 2-((benzyloxy)methyl)-4-chloro-5-((2-hydroxyethyl)amino)pyridazin-3(2H)-one 3005 (3.0 g, 0.0097 mol) in t-BuOH (120 mL) at room temperature were added ethyl (E)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)acrylate 3006 (2.63 g, 0.012 mol), Pd2(dba)3 (0.27 g, 0.0003 mol), XPhos (0.55 g, 0.0012 mol) and K3PO4H2O (5.58 g, 0.024 mol). The reaction mixture was stirred at 130° C. for 10 min with N2 under microwave. The reaction solution was quenched with water and extracted with EtOAc (100 mL×3). The organic phase was concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=90:10 to 0:100) to obtain ethyl (E)-3-(2-((benzyloxy)methyl)-5-((2-hydroxyethyl)amino)-3-oxo-2,3-dihydropyridazin-4-yl)acrylate 3007 (1.2 g, 95% purity, 32% yield) as yellow solid.
LCMS (ESI) calcd for C19H23N3O5 [M+H]+m/z 374.16, found 374.10.
To a solution of ethyl (E)-3-(2-((benzyloxy)methyl)-5-((2-hydroxyethyl)amino)-3-oxo-2,3-dihydropyridazin-4-yl)acrylate 3007 (1.2 g, 0.0032 mol) in DCM (5 mL) and MeOH (20 mL) at rt was added Pd/C (0.29 g, 0.0013 mol). The reaction mixture was stirred at rt for 4 h. The reaction solution was filtered and concentrated under reduced pressure to obtain ethyl 3-(2-((benzyloxy)methyl)-5-((2-hydroxyethyl)amino)-3-oxo-2,3-dihydropyridazin-4-yl)propanoate 3008 (1.1 g, 95% purity, 87% yield) as yellow oil.
LCMS (ESI) calcd for C19H25N3O5 [M+H]+m/z 376.18, found 376.05.
To a solution of ethyl 3-(2-((benzyloxy)methyl)-5-((2-hydroxyethyl)amino)-3-oxo-2,3-dihydropyridazin-4-yl)propanoate 3008 (1.1 g, 0.0029 mol) in EtOH (50 mL) at rt were added 10% HCl aqueous solution (20 mL). The reaction mixture was stirred at 80° C. for 8 h. Then the reaction was quenched with water and adjusted pH to 7˜8 with 1 M NaOH aqueous at 0° C. The reaction solution was extracted with EtOAc (50 mL×3). The organic phase was concentrated under reduced pressure and the residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 0:100) to give 6-((benzyloxy)methyl)-1-(2-hydroxyethyl)-4,6-dihydropyrido[2,3-d]pyridazine-2,5(1H,3H)-dione 3009 (0.85 g, 95% purity, 86% yield) as yellow solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 8.20 (s, 1H), 7.40-7.23 (m, 5H), 5.44 (s, 2H), 4.89 (t, J=6.0 Hz, 1H), 4.64 (s, 1H), 3.94 (t, J=5.6 Hz, 1H), 3.58-3.50 (m, 1H), 2.73 (t, J=8.0 Hz, 1H), 2.60 (t, J=8.0 Hz, 1H).
LCMS (ESI) calcd for C17H19N3O4 [M+H]+ m/z 330.14, found 330.10.
To a solution of 6-((benzyloxy)methyl)-1-(2-hydroxyethyl)-4,6-dihydropyrido[2,3-d]pyridazine-2,5(1H,3H)-dione 3009 (140 mg, 0.425 mmol) in DCM (100 mL) were added 1-(4-(5-(trifluoromethyl)pyridin-2-yl)piperazin-1-yl)prop-2-yn-1-one (120 mg, 0.425 mmol), P(n-Bu)3 (135 mg, 0.425 mmol) successively at room temperature. The reaction mixture was stirred at room temperature for 2 h then concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluting with EtOAc/PE, 50% to 100%) to give (E)-6-((benzyloxy)methyl)-1-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyridin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-4,6-dihydropyrido[2,3-d]pyridazine-2,5(1H,3H)-dione 3010 (150 mg, 90% purity, 52% yield) as a yellow solid.
LCMS (ESI) calcd for C30H31F3N6O5[M+H]+ m/z 613.23, found 613.10.
To a solution of (E)-6-((benzyloxy)methyl)-1-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyridin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-4,6-dihydropyrido[2,3-d]pyridazine-2,5(1H,3H)-dione 3010 (140 mg, 0.229 mmol) in MeOH (20 mL) was added 10% Pd/C (140 mg). The mixture was evacuated and backfilled with hydrogen three times and then charged with hydrogen. The resulting mixture was stirred at rt for 2 h. Then the mixture was filtered through celite, concentrated under vacuum and purified by flash column chromatography (eluting with MeOH/DCM, 0% to 10%) to afford 6-((benzyloxy)methyl)-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyridin-2-yl)piperazin-1-yl)propoxy)ethyl)-4,6-dihydropyrido[2,3-d]pyridazine-2,5(1H,3H)-dione 3011 (115 mg, 90% purity, 74% yield) as a yellow solid.
LCMS (ESI) calcd for C30H33F3N6O5[M+H]+ m/z 615.25, found 615.30.
A solution of 6-((benzyloxy)methyl)-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyridin-2-yl)piperazin-1-yl)propoxy)ethyl)-4,6-dihydropyrido[2,3-d]pyridazine-2,5(1H,3H)-dione 3011 (115 mg, 0.187 mmol) in TFA (5 mL) was stirred at room temperature for 2 h. The pH was adjusted to around 8 by progressively adding saturated aqueous NaHCO3 at 0° C. The mixture was then extracted with EtOAc. The combined organic layers were concentrated under reduced pressure. The residue was purified on a Biotage Isolera One (C18 column, eluting with 0% to 55% MeCN/H2O containing 0.1% formic acid) to provide 1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyridin-2-yl)piperazin-1-yl)propoxy)ethyl)-4,6-dihydropyrido[2,3-d]pyridazine-2,5(1H,3H)-dione 240 (34.0 mg, 93% purity, 35% yield) as a solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ:12.91 (s, 1H), 8.43 (s, 1H), 8.07 (s, 1H), 7.83 (dd, J=9.2, 2.4 Hz, 1H), 6.96 (d, J=9.2 Hz, 1H), 4.02 (t, J=5.6 Hz, 2H), 3.66-3.61 (m, 6H), 3.56-3.50 (m, 6H), 2.71-2.63 (m, 2H), 2.62-2.55 (m, 2H), 2.55-2.51 (m, 2H).
LCMS (ESI) calcd for C22H25F3N6O4[M+H]+ m/z 495.19, found 495.25.
2-chloro-5-fluoropyrimidine 3101 (500 mg, 3.77 mmol), tert-butyl piperazine-1-carboxylate 3102 (843.28 mg, 4.53 mmol) and DIPEA (975.28 mg, 7.55 mmol) were dissolved in IPA (10 mL). The resulting mixture was heated at 120° C. for 2 hours in a microwave reactor. Then the mixture was cooled to room temperature, diluted with water (30 mL), and extracted with EtOAc (2×30 mL). The organic phases were dried over Na2SO4, filtered, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluting with EtOAc/PE, 0 to 20%) to afford tert-butyl 4-(5-fluoropyrimidin-2-yl)piperazine-1-carboxylate 3103 (300 mg, 85% purity, 24% yield) as a white solid.
LCMS (ESI) calcd for C13H19FN4O2[M−t-Bu+H]+ m/z 227.16, found 227.0.
To a 50 mL round-bottom flask was added tert-butyl 4-(5-fluoropyrimidin-2-yl)piperazine-1-carboxylate 3103 (300 mg, 1.059 mmol) and HCl-dioxane (4 M, 15 mL). The mixture was stirred for 5 hours at room temperature. The reaction mixture was concentrated to afford 5-fluoro-2-(piperazin-1-yl)pyrimidine hydrochloride 3104 (225 mg, 85% purity, 82.6% yield) as white solid.
LCMS (ESI) calcd for C8H11FN4 [M+H]+ m/z 183.11, found 183.0.
To a solution of 5-fluoro-2-(piperazin-1-yl) pyrimidine hydrochloride 3104 (200 mg, 0.44 mmol) in DCM (10 mL) was added 3-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy)propanoic acid 2505 (116 mg, 0.52 mmol), T3P (50% in EtOAc, 560 mg, 0.88 mmol) and DIPEA (284 mg, 2.2 mmol). The reaction mixture was stirred at room temperature for 2 hours. After the reaction was completed, the resulting mixture was diluted with water and extracted with DCM (30 mL×3). The combined organic layers were dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by prep-HPLC (columns: Gemini 5 um C18 150×21.2 mm, mobile phase: ACN-H2O (0.1% FA), gradient: 50%-95%) to give 1-(1-(3-(4-(5-fluoropyrimidin-2-yl)piperazin-1-yl)-3-oxopropoxy)propan-2-yl)-5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 3105 (116 mg, 98% purity, 42% yield) as a white solid.
LCMS (ESI) calcd for C28H30F4N8O4 [M+H]+ m/z 619.24, found 619.0.
TfOH (0.2 mL) was added to a solution of 1-(1-(3-(4-(5-fluoropyrimidin-2-yl)piperazin-1-yl)-3-oxopropoxy)propan-2-yl)-5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 3105 (100 mg, 0.16 mmol) in TFA (10 mL). The reaction mixture was stirred at room temperature for 10 h then adjusted to pH=8 by progressively adding saturated aqueous NaHCO3 at 0° C. Then the mixture was extracted with DCM (30 mL×3). The combined organic layers were washed with brine, dried over Na2SO4, and concentrated under reduced pressure. The residue was purified twice by C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 40%-50%) to give 1-(1-(3-(4-(5-fluoropyrimidin-2-yl)piperazin-1-yl)-3-oxopropoxy)propan-2-yl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one (compounds 248 and 249) (50 mg, 98% purity, 61% yield) as a white solid.
LCMS (ESI) calcd for C20H22F4N8O3[M+H]+ m/z 499.19, found 499.0.
Compounds 248 and 249 were separated by SFC (Column: DAICEL OJ-H 4.6 mm I.D.×250 mmL 5 m; Mobile phase: CO2/MeOH (0.1% FA)=60/40) and concentrated under reduced pressure to afford the first fraction as 248 (16.7 mg, 98% purity, 100% ee, white solid) and the second fraction as 249 (19.3 mg, 98% purity, 97% ee, white solid).
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.84 (s, 1H), 8.65 (s, 1H), 8.47 (s, 2H), 5.26-5.08 (m, 1H), 3.78-3.72 (m, 1H), 3.71-3.62 (m, 2H), 3.62-3.55 (m, 4H), 3.54-3.46 (m, 1H), 3.46-3.36 (m, 4H), 2.45-2.38 (m, 2H), 1.49 (d, J=6.8 Hz, 3H).
LCMS (ESI) calcd for C20H22F4N8O3[M+H]+ m/z 499.19, found 499.0.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.84 (s, 1H), 8.65 (s, 1H), 8.47 (s, 2H), 5.22-5.08 (m, 1H), 3.79-3.71 (m, 1H), 3.71-3.63 (m, 2H), 3.63-3.55 (m, 4H), 3.54-3.48 (m, 1H), 3.46-3.37 (m, 4H), 2.46-2.39 (m, 2H), 1.49 (d, J=6.8 Hz, 3H).
LCMS (ESI) calcd for C20H22F4N8O3[M+H]+ m/z 499.19, found 499.0.
To a suspension of NaH (60%, 0.98 g, 0.0245 mol) in DMF (50 mL) was added dropwise a solution of methyl 3-bromo-1H-pyrrole-2-carboxylate 3201 (1 g, 0.0049 mol) and 2-bromoacetonitrile (2.94 g, 0.0245 mmol) in DMF (10 mL) at 0° C. under N2 atmosphere. The reaction mixture was warmed to 70° C. and kept stirring at 70° C. for an additional 2 h. After completion of reaction, the reaction mixture was cooled to rt and then poured into cold saturated aqueous NH4Cl. The resulting solution was extracted with EtOAc (50 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash silica chromatography (eluting with EtOAc/PE, 0% to 10%) to give methyl 3-bromo-1-(cyanomethyl)-1H-pyrrole-2-carboxylate 3202 (0.8 g, 90% purity, 31% yield) as a white solid.
To a stirred solution of methyl 3-bromo-1-(cyanomethyl)pyrrole-2-carboxylate 3202 (800 mg, 3.29 mmol), CuI (626 mg, 3.29 mmol), HMPA (2949 mg, 16.46 mmol) in NMP (20 mL) was added methyl 2,2-difluoro-2-(fluorosulfonyl)acetate 3203 (3161 mg, 16.46 mmol) at rt. The solution was then stirred at 110° C. for 3 h. The resulting reaction solution was filtered, and the filtrate was purified directly by flash silica chromatography (eluting with EtOAc/PE, 10% to 20%) to give 1-(cyanomethyl)-3-(trifluoromethyl)-1H-pyrrole-2-carboxylate 3204 (250 mg, 90% purity, 29% yield) as yellow solid.
To a solution of methyl 1-(cyanomethyl)-3-(trifluoromethyl)-1H-pyrrole-2-carboxylate 3204 (100 mg, 0.429 mmol) in DCE (5 mL) was added NBS (114 mg, 0.643 mmol) and TFA (24 mg, 0.214 mmol) at rt. The mixture was heated at 80° C. for 16 hours. The resulting mixture was diluted with water (30 mL) and extracted with DCM (10 mL×3). The combine organic phases were dried over sodium sulfate, concentrated, and purified by silica gel column chromatography (eluting with EtOAc/PE, 10% to 20%) to give methyl 5-bromo-1-(cyanomethyl)-3-(trifluoromethyl)-1H-pyrrole-2-carboxylate 3205 (40 mg, 90% purity, 26% yield) as a white solid.
To a solution of methyl 5-bromo-1-(cyanomethyl)-3-(trifluoromethyl)-1H-pyrrole-2-carboxylate 3205 (600 mg, 1.9289 mmol) in THF (10 mL) was added slowly BH3-THF (1 M, 9.6 mL, 9.6 mmol) at 0° C. After completion of addition, the reaction solution was warmed to rt and kept stirring at rt for an additional 16 h. The resulting reaction solution was added dropwise MeOH (50 mL) to quench the BH3-THF at rt and then concentrated under reduced pressure. The residue was diluted with NH3-MeOH (7 M, 12.3 mL) and kept stirring at rt overnight. LCMS monitored the formation of product, the reaction mixture was concentrated, and purified by silica gel column chromatography (eluting with EtOAc/PE, 30% to 70%) to give 6-bromo-8-(trifluoromethyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one 3206 (250 mg, purity 90%, 41% yield) as a white solid.
LCMS (ESI) calcd for C8H6BrF3N2O [M+H]+ m/z 282.96, found 282.95.
To a solution of t-BuOK (0.2 g, 1.77 mmol) in DMF (10 mL) was added slowly a solution of 6-bromo-8-(trifluoromethyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one 3206 (0.25 g, 0.883 mmol) and PMBCl (0.28 g, 1.77 mmol) in DMF (5 mL) at 0° C. under N2 atmosphere. After completion of addition, the reaction was warmed to rt and kept stirring for an additional 1.5 h. The resulting reaction mixture was poured into cold saturated aqueous NH4Cl and stirred for 5 min. Then the solution was extracted with EtOAc (50 mL×3). The combined organic layer was washed with bine (30 mL×3), dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash silica chromatography (eluting with EtOAc/PE, 20% to 40%) to give 6-bromo-2-(4-methoxybenzyl)-8-(trifluoromethyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one 3207 (0.2 g, 90% purity, 50% yield) as a white solid.
LCMS (ESI) calcd for C16H14BrF3N2O2 [M+H]+ m/z 403.02, found 403.10.
A suspension of 6-bromo-2-(4-methoxybenzyl)-8-(trifluoromethyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one 3207 (200 mg, 0.50 mmol), K2CO3 (137 mg, 0.99 mmol) and Pd(dppf)Cl2 (36 mg, 0.496 mmol) in Dioxane/H2O (10/1, 10 mL) was heated at 100° C. for 2 h under N2. After cooling to rt, the reaction mixture was poured into ice water and then extracted with EtOAc (30 mL×3). The combined organic layers were washed with water, dried over Na2SO4, and concentrated under reduced pressure. The residue was purified by flash silica chromatography (eluting with EtOAc/PE, 0 to 35%) to give (E)-6-(2-ethoxyvinyl)-2-(4-methoxybenzyl)-8-(trifluoromethyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one 3209 (120 mg, 90% purity, 55% yield) as a white solid.
LCMS (ESI) calcd for C20H21F3N2O3 [M+H]+ m/z 395.15, found 395.10.
To a solution of (E)-6-(2-ethoxyvinyl)-2-(4-methoxybenzyl)-8-(trifluoromethyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one 3209 (120 mg, 0.304 mmol) in DCM (8 mL) was added HCl in dioxane (4 M, 2 mL) dropwise at rt. The mixture was stirred at rt for 5 min. The resulting mixture was concentrated under reduced pressure to give 2-(2-(4-methoxybenzyl)-1-oxo-8-(trifluoromethyl)-1,2,3,4-tetrahydropyrrolo [1,2-a]pyrazin-6-yl)acetaldehyde 3210 (100 mg, 50% purity, 44% yield) as a yellow oil.
LCMS (ESI) calcd for C18H17F3N2O3[M+H]+ m/z 367.12, found 367.10.
To a solution of 2-(2-(4-methoxybenzyl)-1-oxo-8-(trifluoromethyl)-1,2,3,4-tetrahydropyrrolo [1,2-a]pyrazin-6-yl)acetaldehyde 3210 (100 mg, 0.273 mmol) in MeOH (10 mL) was added NaBH4 (20 mg, 0.546 mmol) at rt. The reaction mixture was stirred at rt for 10 min. The resulting reaction solution was quenched with water and then extracted with EtOAc (50 mL×3). The combined organic layers were dried over Na2SO4, concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with EtOAc/PE, 30% to 60%) to obtained 6-(2-hydroxyethyl)-2-(4-methoxybenzyl)-8-(trifluoromethyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one 3211 (40 mg, 90% purity, 35% yield) as a white solid.
LCMS (ESI) calcd for C18H19F3N2O3[M+H]+ m/z 369.14, found 369.00.
To a solution of 6-(2-hydroxyethyl)-2-(4-methoxybenzyl)-8-(trifluoromethyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one 3211 (40 mg, 0.11 mmol) in DCM (5 mL) were added 1-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-2-yn-1-one (34 mg, 0.12 mmol) and P(n-Bu)3 (2 mg, 0.011 mmol) at rt successively. The reaction mixture was stirred at room temperature for 2 h. The reaction mixture was concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with MeOH/DCM, 0% to 5%) to afford (E)-2-(4-methoxybenzyl)-6-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-8-(trifluoromethyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one 3212 (60 mg, 90% purity, 76% yield) as a white solid.
LCMS (ESI) calcd for C30H30F6N6O4[M+Na]+ m/z 675.22, found 675.25.
A solution of (E)-2-(4-methoxybenzyl)-6-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)-8-(trifluoromethyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one 3212 (60 mg, 0.09 mmol) and Pd/C (10%, 6 mg) in MeOH (6 mL) was stirred at rt for 16 h under H2 atmosphere. The resulting solution was filtered, and the filter cake was washed with MeOH three times. The filtrate was concentrated under reduced pressure to afford 2-(4-methoxybenzyl)-6-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-8-(trifluoromethyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one 3213 (50 mg, 90% purity, 74% yield) as a white solid.
LCMS (ESI) calcd for C30H32F6N6O4[M+H]+ m/z 655.24, found 655.35.
TfOH (0.5 mL) was added to a solution of 2-(4-methoxybenzyl)-6-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-8-(trifluoromethyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one 3213 (50 mg, 0.076 mmol) in TFA (2 mL). The reaction mixture was stirred at rt for 30 min. The pH of the resulting mixture was adjusted to around 8 by progressively adding saturated NaHCO3 solution at 0° C., and then extracted with DCM (50 mL×3). The combined organic layers were washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified with C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 40-60) to give 6-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)-8-(trifluoromethyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-1(2H)-one 316 (14.5 mg, 94% purity, 34% yield) as a white solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 8.73 (s, 2H), 7.92 (s, 1H), 6.32 (s, 1H), 4.08-4.01 (m, 2H), 3.86-3.75 (m, 4H), 3.69-3.60 (m, 4H), 3.58-3.52 (m, 4H), 3.50-3.44 (m, 2H), 2.83 (t, J=6.4 Hz, 2H), 2.61 (t, J=6.4 Hz, 2H).
LCMS (ESI) calcd for C22H24F6N6O3[M+H]+ m/z 535.18, found 535.05.
To a solution of 1-(2-hydroxyethyl)-5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 1910 (100 mg, 0.27 mmol) in n-Hexane (2 mL) were added Ag2O (252 mg, 1.09 mmol) and MgSO4 (130 mg, 1.08 mmol) successively at 80° C. under N2. After the reaction mixture was refluxed for 1 h, ethyl 2-bromoacetate 3302 (317 mg, 1.90 mmol) was added to the solution. The mixture was refluxed for additional 18 h. Then it was cooled to rt. The reaction mixture was poured into cold water and then extracted with EtOAc (50 mL×3), dried over anhydrous sodium sulfate and concentrated in vacuo. The residue was purified by Flash chromatography (eluting with PE/EtOAc=70:30 to 30:70) to afford ethyl 2-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy)acetate 3303 (80 mg, 90% purity, 58% yield) as colorless oil.
LCMS (ESI) calcd for C20H21F3N4O5[M+H]+ m/z 455.15, found 455.20.
LiOH (13 mg, 0.53 mmol) was added to a solution of ethyl 2-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy)acetate 3303 (80 mg, 0.18 mmol) in THF/H2O (THF:H2O=3:1, 4 mL). After stirring at rt for 3 h, the reaction mixture was concentrated under reduced pressure to remove THF. The obtained aqueous was acidified with HCl solution (1 mol/L) and extracted with DCM (20 mL×3). The combined organic layers were washed with brine, dried over Na2SO4 and concentrated under reduced pressure to give 2-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy)acetic acid 3304 (70 mg, 80% purity, 74% yield) as a colorless oil.
LCMS (ESI) calcd for C18H17F3N4O5[M+H]+ m/z 427.12, found 427.25.
To a solution of 2-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy)acetic acid 3304 (70 mg, 0.16 mmol) in DCM (2 mL) were added N-methyl-1-(5-(trifluoromethyl)pyrimidin-2-yl)piperidin-4-amine hydrochloride 3305 (51 mg, 0.20 mmol), DIPEA (106 mg, 0.82 mmol), T3P (50% in EtOAc, 157 mg, 0.25 mmol) at room temperature successively. The mixture was stirred at room temperature for 2 h. The resulting mixture was diluted with water and extracted with DCM (30 mL×3). The combined organic layers were dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by C18 column (mobile phase: ACN-H2O (0.1% FA), gradient: 0%-100%) to obtain 2-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy)-N-methyl-N-(1-(5-(trifluoromethyl)pyrimidin-2-yl)piperidin-4-yl)acetamide 3306 (80 mg, 90% purity, 65% yield) as white solid.
LCMS (ESI) calcd for C29H30F6N8O4 [M+H]+m/z 669.23, found 669.33.
To a solution of 2-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy)-N-methyl-N-(1-(5-(trifluoromethyl)pyrimidin-2-yl)piperidin-4-yl)acetamide 3306 (80 mg, 0.12 mmol) in TFA (3 mL) was added TfOH (1 mL) dropwise at rt. After completion of addition, the reaction solution was stirred at rt for 20 min. The resulting mixture was adjusted pH to 8 with saturated aqueous NaHCO3 at 0° C., then extracted with DCM (30 mL×3). The combined organic phases were concentrated under reduced pressure. The residue was purified by prep-HPLC (Gemini 5 um C18 column, 150×21.2 mm, eluting with 30% to 95% MeCN/H2O containing 0.1% FA) and C18 column (mobile phase: ACN-H2O (0.1% FA), gradient: 0%-100%) to obtain N-methyl-2-(2-(4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)ethoxy)-N-(1-(5-(trifluoromethyl)pyrimidin-2-yl)piperidin-4-yl)acetamide 317 (9.9 mg, 100% purity, 15% yield) as a white solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ:12.62 (s, 1H), 8.62 (s, 2H), 8.59 (s, 1H), 4.80 (d, J=13.2 Hz, 2H), 4.73 (t, J=5.2 Hz, 2H), 4.59-4.05 (m, 3H), 3.91 (t, J=4.8 Hz, 2H), 2.96 (t, J=12.0 Hz, 2H), 2.59 (s, 3H), 1.66-1.53 (m, 4H).
LCMS (ESI) calcd for C21H22F6N8O3[M+H]+ m/z 549.17, found 549.25.
To a solution of 3-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl) propoxy) propanoic acid 2505 (150 mg, 0.33 mmol) in DMF (5 mL) were added 2-(piperazin-1-yl) pyrimidine-5-carbonitrile hydrochloride 3402 (112 mg, 0.50 mmol), DIPEA (2123 mg, 1.65 mmol), HATU (158 mg, 0.50 mmol) at rt successively. The reaction mixture was stirred at rt for 1 h. The reaction mixture was diluted with water (15 mL) and extracted with EtOAc (15 mL×3). The combined organic layer was washed with brine, dried over Na2SO4. The combined organic phases were concentrated and purified by C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 47-50) to afford 2-(4-(3-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl) propoxy) propanoyl) piperazin-1-yl) pyrimidine-5-carbonitrile 3403 (90 mg, 95% purity, 41% yield) as a yellow solid.
LCMS (ESI) calcd for C29H30F3N9O4[M+H]+ m/z 626.24, found 626.39
To a stirred solution of 2-(4-(3-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl) propoxy) propanoyl) piperazin-1-yl) pyrimidine-5-carbo nitrile 3403 (80 mg, 0.13 mmol) in TFA (5 mL) was added TfOH (0.1 mL) at rt. The mixture was stirred at rt for 10 min. The resulting solution was adjusted to pH 7-8 with saturated aqueous NaHCO3 at 0° C. and extracted with DCM. The combined organic phases were washed with water and brine, dried over sodium sulfate, concentrated under vacuum, and purified by C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 45-47) to afford 2-(4-(3-(2-(4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl) propoxy) propanoyl) piperazin-1-yl) pyrimidine-5-carbonitrile (a mixture of compounds 321 and 322) (20 mg, 95% purity) as a green solid.
Compounds 321 and 322 were separated by SFC (Column: Daicel OJ-H 20 mm I.D.×250 mmL 5 m; Mobile phase: CO2/MeOH (0.1% FA)=60/40) and concentrated under reduced pressure to afford the first fraction as 321 (6.3 mg, 98% purity, 100% ee, green solid) and the second fraction as 322 (8.9 mg, 98% purity, 100% ee, green solid).
1H NMR (400 MHz, DMSO-d6, ppm) δ:12.83 (s, 1H), 8.78 (s, 2H), 8.64 (s, 1H), 5.25-5.06 (m, 1H), 3.77-3.65 (m, 7H), 3.53-3.40 (m, 5H), 2.47-2.41 (m, 2H), 1.49 (d, J=6.8 Hz, 3H).
LCMS (ESI) calcd. for C21H22F3N9O3[M+H]+ m/z 506.18, found 506.25.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.83 (s, 1H), 8.78 (s, 2H), 8.64 (s, 1H), 5.25-5.11 (m, 1H), 3.78-3.65 (m, 7H), 3.53-3.40 (m, 5H), 2.45-2.40 (m, 2H), 1.49 (d, J=6.8 Hz, 3H).
LCMS (ESI) calcd. for C21H22F3N9O3[M+H]+ m/z 506.18, found 506.25.
To a solution of 5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 1908 (1.0 g, 0.0030 mol) in MeCN (50 mL) were added ethyl (E)-but-2-enoate 3502 (0.99 g, 0.0086 mol) and KF (0.36 g, 0.0062 mol) at room temperature. The reaction mixture was stirred at 80° C. for 18 h. The reaction solution was quenched with water and extracted with EtOAc (50 mL×3). The organic phases were concentrated under reduced pressure and the residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 80:20) to give ethyl 3-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)butanoate 3503 (0.7 g, 70% purity, 35% yield) as a yellow oil.
LCMS (ESI) calcd for C20H21F3N4O4[M+H]+ m/z 439.15, found 439.05.
To a solution of ethyl 3-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)butanoate 3503 (1 g, 0.0023 mol) in EtOH (100 mL) were added NaBH4 (0.35 g, 0.0092 mol) and LiCl (0.39 g, 0.0092 mol) at 0° C. The reaction mixture was stirred at room temperature for 1 h. The reaction solution was quenched with water and extracted with EtOAc (50 mL×3). The combined organic phases were concentrated under reduced pressure and the residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 70:30) to give 1-(4-hydroxybutan-2-yl)-5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 3504 (0.68 g, 90% purity, 65% yield) as a yellow solid.
LCMS (ESI) calcd for C18H19F3N4O3[M+H]+ m/z 397.14, found 397.25.
To a solution of 1-(4-hydroxybutan-2-yl)-5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 3504 (680 mg, 1.72 mmol) in hexane (50 mL) were added ethyl 2-bromoacetate 3505 (2.86 g, 17.2 mmol), Ag2O (3.18 g, 13.72 mmol) and MgSO4 (0.823 g, 6.86 mmol) at room temperature. The reaction mixture was stirred at 80° C. for 18 h. The resulting solution was filtered through celite and the filter cake was washed with DCM (5 mL×4). The filtrate was concentrated under reduced pressure and the residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 70:30) to give ethyl 2-(3-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)butoxy)acetate 3506 (520 mg, 70% purity, 43% yield) as a yellow oil.
LCMS (ESI) calcd for C22H25F3N4O5[M+H]+ m/z 483.15, found 483.35.
To a solution of ethyl 2-(3-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)butoxy)acetate 3506 (500 mg, 1.036 mmol) in THF/H2O (3:1, 30 mL) was added LiOH (25 mg, 1.03 mmol) at room temperature. The reaction mixture was stirred at room temperature for 1 h. The reaction solution was adjusted pH to 4 with 1 M aqueous HCl. The water phase was on a Biotage Isolera One (C18 column, eluting with 60% to 90% MeCN/H2O containing 0.1% formic acid) to obtain 2-(3-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)butoxy)acetic acid 3507 (300 mg, 50% purity, 31% yield) as a white solid.
LCMS (ESI) calcd for C20H21F3N4O5[M+H]+ m/z 455.15, found 455.25.
To a solution of 2-(3-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)butoxy)acetic acid 3507 (300 mg, 0.33 mmol) in DCM (10 mL) were added 2-(piperazin-1-yl)-5-(trifluoromethyl)pyrimidine hydrochloride (92 mg, 0.40 mmol), T3P (50% wt in EtOAc, 420 mg, 0.66 mmol), DIPEA (128 mg, 0.99 mmol) at room temperature successively. The mixture was kept stirring at room temperature for 1 h. The resulting mixture was diluted with water and extracted with DCM (20 mL×3). The combined organic layer was dried over Na2SO4 and concentrated under reduced pressure. The residue was purified on a Biotage Isolera One (C18 column, eluting with 60% to 90% MeCN/H2O containing 0.1% formic acid) to give 5-(4-methoxybenzyl)-1-(4-(2-oxo-2-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)ethoxy)butan-2-yl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 3508 (110 mg, 80% purity, 39% yield) as a white solid.
LCMS (ESI) calcd for C29H30F6N8O4[M+H]+ m/z 669.23, found 669.20.
To a solution of 5-(4-methoxybenzyl)-1-(4-(2-oxo-2-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)ethoxy)butan-2-yl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 3508 (110 mg, 0.16 mmol) in TFA (5 mL) was added TfOH (123 mg, 0.82 mmol) at room temperature. The reaction mixture was stirred at room temperature for 0.5 h. The reaction solution was adjusted pH to 7-8 with saturated aqueous NaHCO3 at 0° C. The solution was extracted with EtOAc. The combined organic phases were concentrated and purified on a Biotage Isolera One (C18 column, eluting with 60% to 90% MeCN/H2O containing 0.1% formic acid) to provide 1-(4-(2-oxo-2-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)ethoxy)butan-2-yl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 327 and 328 (60 mg, 95% purity, 63% yield) as a white solid.
LCMS (ESI) calcd for C21H22F6N8O3[M+H]+ m/z 549.17, found 549.10.
Compounds 327 and 328 were separated by SFC (Column: CHIRALPAK OJ-H, 250 mm×20 mm I.D., 5 mm; Mobile phase: CO2/IPA=85/15) and concentrated under reduced pressure to afford the first fraction as 327 (20.2 mg, 100% purity, 100% ee, white solid) and the second fraction as 328 (17.9 mg, 99% purity, 95% ee, white solid).
1H NMR (400 MHz, DMSO-d6, ppm) δ:12.85 (s, 1H), 8.73 (s, 2H), 8.67 (s, 1H), 5.13-5.15 (m, 1H), 4.07 (s, 2H), 3.86-3.76 (m, 4H), 3.56-3.47 (m, 2H), 3.45-3.37 (m, 3H), 3.18-3.08 (m, 1H), 2.19-2.10 (m, 2H), 1.55 (d, J=6.8 Hz, 3H).
LCMS (ESI) calcd for C21H22F6N8O3[M+H]+ m/z 549.17, found 549.30.
1H NMR (400 MHz, DMSO-d6, ppm) δ:12.85 (s, 1H), 8.73 (s, 2H), 8.67 (s, 1H), 5.10-5.15 (m, 1H), 4.07 (s, 2H), 3.87-3.73 (m, 4H), 3.56-3.46 (m, 2H), 3.45-3.37 (m, 3H), 3.17-3.09 (m, 1H), 2.17-2.09 (m, 2H), 1.55 (d, J=6.8 Hz, 3H).
LCMS (ESI) calcd for C21H22F6N8O3[M+H]+ m/z 549.17, found 549.30.
To a solution of ethyl 2-methyl-1H-pyrrole-3-carboxylate 3601 (45 g, 293.8 mmol) in THF (1000 mL) was added NaH (23.5 g, 587.6 mmol, 60% wt) at 00° C. The reaction mixture was stirred at 0° C. for 10 min SEMCl (58.8 g, 352.5 mmol) was added dropwise at 0° C. The reaction mixture was stirred at room temperature for 5 h. The reaction mixture was quenched with cold water and then extracted with EtOAc (300 mL×3). The combined organic layers were concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=85:15 to 70:30) to afford ethyl 2-methyl-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-pyrrole-3-carboxylate 3602 (52 g, 90% purity, 56% yield) as a yellow oil.
LCMS (ESI) calcd for Cl4H25NO3Si [M+H]+ m/z 284.16, found 284.25.
To a solution of ethyl 2-methyl-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-pyrrole-3-carboxylate 3602 (50 g, 175.8 mmol) in THF/AcOH/H2O (800 mL, 1:1:1) was added CAN (385.5 g, 703.2 mmol) at 0° C. The reaction mixture was stirred at room temperature for 1 h. The reaction mixture was poured into ice-water (500 mL) and stirred for another 30 min. The resulting solution was extracted with EtOAc (300 mL×3). The combined organic layer was washed with brine, dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=100:0 to 80:20) to obtain ethyl 2-formyl-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-pyrrole-3-carboxylate 3603 (18 g, 90% purity, 31% yield) as a yellow oil.
LCMS (ESI) calcd for C14H23NO4Si [M+H]+ m/z 298.14, found 298.18.
To a solution of ethyl 2-formyl-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-pyrrole-3-carboxylate 3603 (18 g, 60.3 mmol) in ACN (300 mL) was added NBS (10.7 g, 60.3 mmol) at rt. The reaction mixture was stirred at rt for 2 h. The reaction mixture was concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=85:15 to 70:30) to afford ethyl 4-bromo-2-formyl-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-pyrrole-3-carboxylate 3604 (15 g, 90% purity, 59% yield) as a yellow oil.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 10.12 (s, 1H), 7.78 (s, 1H), 5.68 (s, 2H), 4.44-4.33 (m, 2H), 3.58-3.53 (m, 2H), 1.38 (t, J=7.2 Hz, 3H), 0.88 (t, J=7.8 Hz, 2H), 0.00 (s, 9H).
To a solution of ethyl 4-bromo-2-formyl-1-((2-(trimethylsilyl)ethoxy)methyl)-1H-pyrrole-3-carboxylate 3604 (10 g, 26.5 mmol) in EtOH (50 mL) was added (2-methoxy-5-methylphenyl) hydrazine 3605 (8.1 g, 53 mmol) at rt. The reaction mixture was stirred at 80° C. for 1 h. The reaction solution was concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=85:15 to 20:80) to afford 3-bromo-5-(4-methoxybenzyl)-1-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 3606 (8.3 g, 90% purity, 60% yield) as a yellow solid.
LCMS (ESI) calcd for C20H26BrN3O3Si [M+H]+ m/z 464.09, found 464.18.
A solution of 3-bromo-5-(4-methoxybenzyl)-1-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 3606 (8.2 g, 17.6 mmol) in HCl-dioxane (150 mL, 4 M) was prepared at rt. The reaction mixture was stirred at 50° C. for 16 h in a sealed tube. After LCMS showed 3607 was formed the reaction solution was concentrated under reduced pressure. The residue was dissolved in EtOH/H2O (100 mL, 5:1), K2CO3 (24.3 g, 0.18 mmol) was added at rt. The reaction mixture was stirred at rt for 2 h. The reaction solution was diluted with H2O (200 mL), the aqueous layer was extracted with EtOAc (100 mL×3). The combined organic layers were concentrated under reduced pressure to give 3-bromo-5-(4-methoxybenzyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 3608 (5.8 g, 80% purity, 79% yield) as a yellow solid.
LCMS (ESI) calcd for C14H12BrN3O2 [M+H]+ m/z 334.01, found 334.07.
To a solution of 3-bromo-5-(4-methoxybenzyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 3608 (6 g, 18 mmol) in THE (100 mL) was added NaH (2.2 g, 54 mmol, 60% wt) at 0° C. The reaction mixture was stirred at 0° C. for 10 min. Ethyl 2-bromopropanoate 3609 (4.9 g, 27 mmol) was added dropwise at 0° C. The reaction mixture was stirred at room temperature for 12 h. The reaction mixture was quenched with cold water and then extracted with EtOAc (100 mL×3). The combined organic layers were concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=85:15 to 60:40) to afford ethyl 2-(3-bromo-5-(4-methoxybenzyl)-4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 3610 (3.0 g, 90% purity, 34% yield) as a yellow solid.
LCMS (ESI) calcd for C19H20BrN3O4[M+H]+ m/z 434.06, found 434.15.
To a solution of ethyl 2-(3-bromo-5-(4-methoxybenzyl)-4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 3610 (4.0 g, 9.2 mmol) in ACN (30 mL) were added tributyl(vinyl)stannane 3611 (5.83 g, 18.4 mmol) and Pd(AMPHOS)Cl2 (650 mg, 0.9 mmol) at rt. The resulting mixture was stirred at 100° C. for 1 h in a sealed tube. After cooling to rt, the mixture was concentrated in vacuo. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 60:40) to obtain ethyl 2-(5-(4-methoxybenzyl)-4-oxo-3-vinyl-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 3612 (2.96 g, 90% purity, 76% yield) as a white solid.
LCMS (ESI) calcd for C21H23N3O4 [M+H]+ m/z 382.17, found 382.19.
To a solution of ethyl 2-(5-(4-methoxybenzyl)-4-oxo-3-vinyl-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 3612 (3 g, 7.9 mmol) in 1,4-dioxane/H2O (2:1, 50 mL) were added K2OsO4·2H2O (290 mg, 0.8 mmol) and NaIO4 (6.76 g, 31.6 mmol) at rt. The reaction mixture was stirred at rt for 5 h. The resulting mixture was diluted with water (50 mL) and extracted with EtOAc (100 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure. The residue was purified by flash chromatography (eluting with PE/EtOAc=100:0 to 50:50) to give ethyl 2-(3-formyl-5-(4-methoxybenzyl)-4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 3613 (1.7 g, 90% purity, 51% yield) as a yellow oil.
LCMS (ESI) calcd for C20H21N3O5 [M+H]+ m/z 384.15, found 384.19.
To a solution of ethyl 2-(3-formyl-5-(4-methoxybenzyl)-4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 3613 (1.7 g, 4.4 mmol) in DCM (50 mL) was added DAST (7.1 g, 44.0 mmol) at 0° C. The reaction mixture was stirred at rt for 16 h. The reaction solution was adjusted to pH 8-9 with saturated aq. NaHCO3 at 0° C. The aqueous layer was extracted with EtOAc (50 mL×3). The combined organic layers were concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=85:15 to 70:30) to afford ethyl 2-(3-(difluoromethyl)-5-(4-methoxybenzyl)-4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 3614 (1.36 g, 90% purity, 68% yield) as a white solid.
LCMS (ESI) calcd for C20H21F2N3O4[M+H]+ m/z 406.15, found 406.14.
To a solution of ethyl 2-(3-(difluoromethyl)-5-(4-methoxybenzyl)-4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 3614 (1.35 g, 3.3 mmol) in EtOH (30 mL) was added NaBH4 (0.5 g, 13.2 mmol) and LiCl (0.56 g, 13.2 mmol) successively at rt. The reaction was stirred at rt for 2 h. The reaction was quenched with H2O (30 mL) and extracted with EtOAc (30 mL×2). The organic layer was concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=70:30 to 20:80) to afford 3-(difluoromethyl)-1-(1-hydroxypropan-2-yl)-5-(4-methoxybenzyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 3615 (740 mg, 90% purity, 55% yield) as a white solid.
LCMS (ESI) calcd for C18H19F2N3O3[M+H]+ m/z 364.14, found 364.18.
To the solution of 3-(difluoromethyl)-1-(1-hydroxypropan-2-yl)-5-(4-methoxybenzyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 3615 (70 mg, 0.19 mmol) in DCM (5 mL) were added 1-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-2-yn-1-one (66 mg, 0.23 mmol) and P(n-Bu)3 (19 mg, 0.10 mmol) at rt. The reaction mixture was stirred at rt for 2 h. The reaction mixture was diluted with DCM and water. The aqueous layer was extracted with DCM (20 mL×3). The combined organic layers were dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=20:80 to 0:100) to afford (E)-3-(difluoromethyl)-5-(4-methoxybenzyl)-1-(1-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)propan-2-yl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 3616 (135 mg, 90% purity, 97% yield) as a white solid.
LCMS (ESI) calcd for C30H30F5N7O4[M+H]+ m/z 648.23, found 648.37.
A solution of (E)-3-(difluoromethyl)-5-(4-methoxybenzyl)-1-(1-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)propan-2-yl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 3616 (130 mg, 0.20 mmol) and Pd/C (15 mg) in MeOH (10 mL) was stirred at rt for 2 h under H2 atmosphere. The resulting solution was filtered through diatomaceous earth and the filter cake was washed with DCM (5 mL×4). The filtrate was concentrated under reduced pressure to give 3-(difluoromethyl)-5-(4-methoxybenzyl)-1-(1-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)propan-2-yl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 3617 (130 mg, 90% purity, 90% yield) as a white solid.
LCMS (ESI) calcd for C30H32F5N7O4[M+H]+ m/z 650.24, found 650.30.
To a solution of 3-(difluoromethyl)-5-(4-methoxybenzyl)-1-(1-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)propan-2-yl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 3617 (105 mg, 0.16 mmol) in TFA (3 mL) was added TfOH (0.3 mL) at 0° C. The reaction solution was stirred at rt for 1 h. The mixture was adjusted to pH 8-9 with saturated aqueous NaHCO3 at 0° C., then extracted with EtOAc (10 mL×3). The combined organic layers were concentrated under reduced pressure. The residue was purified by C18 column (mobile phase: ACN-H2O (0.1% FA), gradient: 10-95) to give 3-(difluoromethyl)-1-(1-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)propan-2-yl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one (mixture of 395 and 396) as a white solid.
Compounds 395 and 396 were separated by SFC (Column: DAICEL OD-H 4.6 mm I.D.×250 mmL 5 m; Mobile phase: CO2/IPA [0.1% NH3 (7 M Solution in MeOH)]=75/25) and concentrated under reduced pressure to afford the first fraction as 395 (24.3 mg, 100% purity, 99% ee, white solid) and the second fraction as 396 (20.3 mg, 100% purity, 98% ee, white solid).
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.48 (s, 1H), 8.73 (s, 2H), 8.46 (s, 1H), 7.95 (s, 1H), 7.27 (t, J=55.6 Hz, 1H), 4.97-4.84 (m, 1H), 3.82-3.73 (m, 4H), 3.73-3.63 (m, 3H), 3.62-3.54 (m, 1H), 3.53-3.41 (m, 4H), 2.49-2.45 (m, 2H), 1.46 (d, J=6.8 Hz, 3H).
LCMS (ESI) calcd for C22H24F5N7O3[M+H]+ m/z 530.19, found 530.30.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.49 (s, 1H), 8.73 (s, 2H), 8.46 (s, 1H), 7.95 (s, 1H), 7.27 (t, J=55.6 Hz, 1H), 4.98-4.84 (m, 1H), 3.82-3.63 (m, 7H), 3.64-3.54 (m, 1H), 3.53-3.40 (m, 4H), 2.50-2.45 (m, 2H), 1.46 (d, J=6.8 Hz, 3H).
LCMS (ESI) calcd for C22H24F5N7O3[M+H]+ m/z 530.19, found 530.30.
To a solution of 5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 1908 (1 g, 0.0031 mol), ethyl 2-bromopropanoate 3702 (1.68 g, 0.0093 mmol) in DMF (30 mL) was added t-BuOK (1.04 mg, 0.0093 mol) at 0° C. The reaction mixture was stirred at rt for 6 h. The reaction solution was quenched with water and extracted with EtOAc (100 mL×3). The combined organic phases were concentrated under reduced pressure. The residue was purified by silica gel column (eluting with EtOAc/PE, 0 to 50%) to obtain ethyl 2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propanoate 3703 (1.2 g, 90% purity, 80% yield) as a white solid.
LCMS (ESI) calcd for C19H19F3N4O4[M+H]+ m/z 425.14, found 425.05.
To a solution of ethyl 2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propanoate 3703 (1.2 g, 0.0028 mol) in EtOH (30 mL) were added LiCl (0.47 g, 0.0112 mmol) and NaBD4 (0.47 g, 0.0112 mol) at rt. The reaction mixture was stirred at rt for 2 h. The resulting mixture was quenched with water and extracted with EtOAc (50 mL×3). The combined organic layers were washed with brine and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluting with EtOAc/PE, 0 to 80%) to obtain 1-(1-hydroxypropan-2-yl-1,1-d2)-5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 3704 (0.8 g, 90% purity, 67% yield) as white solid.
LCMS (ESI) calcd for C17H15D2F3N4O3 [M+H]+ m/z 385.14, found 385.25.
To a solution of 1-(1-hydroxypropan-2-yl-1,1-d2)-5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 3704 (500 mg, 1.3 mmol), ethyl propiolate 3705 (383 mg, 3.9 mmol) in DCM (10 mL) was added P(n-Bu)3 (132 mg, 0.65 mmol) at rt. The reaction mixture was stirred at rt for 0.5 h. The resulting mixture was quenched with water and extracted with DCM (50 mL×3). The combined organic layer was washed with brine and concentrated under reduced pressure. The residue was purified by silica gel column (eluting with EtOAc/PE, 0 to 100%) to obtain ethyl (E)-3-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy-1,1-d2)acrylate 3706 (600 mg, 90% purity, 86% yield) as a yellow oil.
LCMS (ESI) calcd for C22H21D2F3N4O5 [M+Na]+ m/z 505.17, found 505.05.
To a solution of ethyl (E)-3-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy-1,1-d2)acrylate 3706 (600 mg, 1.24 mmol) in MeOH (20 mL) was added 10% Pd/C (60 mg). The mixture was evacuated and backfilled with hydrogen three times and then charged with hydrogen. The resulting mixture was stirred at room temperature for 2 hours. Then the mixture was filtered through celite and concentrated under vacuum to give crude ethyl 3-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy-1,1-d2)propanoate 3707 (600 mg, 90% purity, 89% yield) which was used directly in next step without further purification.
LCMS (ESI) calcd for C22H23D2F3N4O5 [M+H]+ m/z 485.19, found 485.15.
To a solution of ethyl 3-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy-1,1-d2)propanoate 3707 (600 mg, 1.24 mmol) in MeOH/H2O (3/1, 30 mL) was added LiOH (89 mg, 3.72 mmol). The mixture was stirred at rt for 2 h. The mixture was acidified with 1 M aqueous HCl to pH 4˜5. The water phase was purified by C18 column (Agela 80 g, mobile phase: ACN-H2O (0.1% FA), gradient: 20%-50%) to give 3-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy-1,1-d2)propanoic acid 3708 (400 mg, 90% purity, 63% yield) as a yellow oil.
LCMS (ESI) calcd for C20H19D2F3N4O5 [M+H]+ m/z 457.16, found 457.20.
To a solution of 3-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy-1,1-d2)propanoic acid 3708 (100 mg, 0.22 mmol), 2-(piperazin-1-yl)pyrimidine-5-carbonitrile hydrochloride 3709 (64 mg, 0.28 mmol) and DIPEA (141 mg, 1.1 mmol) in DCM (10 mL) was added T3P (50% in EtOAc, 279 mg, 0.44 mmol) at rt. The mixture was stirred at room temperature for 30 min. The resulting solution was diluted with water (30 mL) and extracted with DCM (30 mL×3). The combined organic layer was dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by C18 column (Agela 80 g, mobile phase: ACN-H2O (0.1% FA), gradient: 20%-80%) to give 2-(4-(3-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy-1,1-d2)propanoyl)piperazin-1-yl)pyrimidine-5-carbonitrile 3710 (100 mg, 90% purity, 81% yield) as a white solid.
LCMS (ESI) calcd for C29H28D2F3N9O4 [M+H]+ m/z 628.25, found 628.20.
To a solution of 2-(4-(3-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy-1,1-d2)propanoyl)piperazin-1-yl)pyrimidine-5-carbonitrile 3710 (100 mg, 0.16 mmol) in TFA (5 mL) was added TfOH (0.2 mL) at rt. The reaction mixture was stirred at rt for 0.5 h. The resulting mixture was diluted with DCM (50 mL) and then adjusted pH to 8 with saturated aqueous NaHCO3 at 0° C. The basified solution was extracted with DCM (20 mL×3). The combined organic layers were washed with brine, dried over Na2SO4, and concentrated under reduced pressure. The crude product was purified by C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 30%-60%) to give 2-(4-(3-(2-(4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy-1,1-d2)propanoyl)piperazin-1-yl)pyrimidine-5-carbonitrile (mixture of compounds 420 and 421) (40 mg, 95% purity, 47% yield) as a white solid.
Compounds 420 and 421 were separated by SFC (Column: DAICEL OJ-H 4.6 mm I.D.×250 mmL 5 m; Mobile phase: CO2/MeOH [0.1% NH3 (7 M Solution in MeOH)]=65/35) and concentrated under reduced pressure to afford the first fraction as 420 (16.8 mg, 98% purity, 100% ee, white solid) and the second fraction as 421 (14 mg, 99% purity, 100% ee, white solid).
1H NMR (400 MHz, DMSO-d6, ppm) δ:12.83 (s, 1H), 8.78 (s, 2H), 8.65 (s, 1H), 5.16 (q, J=6.8 Hz, 1H), 3.78-3.71 (m, 4H), 3.71-3.63 (m, 1H), 3.55-3.49 (m, 1H), 3.48-3.40 (m, 4H), 2.47-2.40 (m, 2H), 1.49 (d, J=6.8 Hz, 3H).
LCMS (ESI) calcd for C21H20D2F3N9O3 [M+H]+ m/z 508.19, found 508.05.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.83 (s, 1H), 8.78 (s, 2H), 8.65 (s, 1H), 5.16 (q, J=6.8 Hz, 1H), 3.78-3.72 (m, 4H), 3.70-3.63 (m, 1H), 3.55-3.49 (m, 1H), 3.48-3.39 (m, 4H), 2.46-2.39 (m, 2H), 1.49 (d, J=6.8 Hz, 3H).
LCMS (ESI) calcd for C21H20D2F3N9O3 [M+H]+ m/z 508.19, found 508.10.
To a solution of 1-(1-hydroxypropan-2-yl)-5-(4-methoxybenzyl)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrazolo[3,4-d]pyridazin-4-one 2304 (250 mg, 0.65 mmol) in hexane (30 mL) were added ethyl 2-bromoacetate 3802 (765 mg, 4.58 mmol), MgSO4 (314 mg, 2.62 mmol), Ag2O (607 mg, 2.62 mmol) at rt successively under an atmosphere of N2. The mixture was heated at 80° C. for 32 h. The mixture was filtered through celite. The filtrate was concentrated under vacuum, purified by flash chromatography (eluting with PE/EtOAc=100:0 to 60:40) to afford ethyl 2-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy) acetate 3803 (140 mg, 90% purity, 41% yield) as clear oil.
LCMS (ESI) calcd C21H23F3N4O5 [M+H]+m/z 469.16, found 469.15.
To a solution of ethyl 2-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl) propoxy) acetate 3803 (190 mg, 0.41 mmol) in THF/H2O=5:1 (5 mL) was added LiOH (30 mg, 1.22 mmol) at rt. The reaction mixture was stirred at rt for 2 h. The solvent was adjusted to pH 2-3 with saturated NH4Cl and extracted with DCM. The combined organic phases were washed with water and brine, dried over sodium sulfate, concentrated under vacuum, and purified by C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 70-80)) to afford 2-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy)acetic acid 3804 (150 mg, 85% purity, 71% yield) as a clear oil.
LCMS (ESI) calcd C19H19F3N4O5[M+H]+ m/z 441.13, found 441.17.
To a solution of 2-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy)acetic acid 3804 (80 mg, 0.18 mmol) in DCM (5 mL) were added N-methyl-1-(5-(trifluoromethyl)pyrimidin-2-yl)piperidin-4-amine hydrochloride 3805 (60 mg, 0.20 mmol), DIPEA (118 mg, 0.91 mmol), T3P (50% wt in EtOAc, 232 mg, 0.36 mmol) at rt successively. The reaction mixture was stirred at rt for 1 h. The reaction solution was quenched with water (10 mL) and extracted with DCM (10 mL×3). The combined organic phases were concentrated and purified by flash chromatography (eluting with PE/EtOAc=100:0 to 80:20) to afford 2-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy)-N-methyl-N-(1-(5-(trifluoromethyl)pyrimidin-2-yl)piperidin-4-yl)acetamide 3806 (70 mg, 90% purity, 50% yield) as a clear oil.
LCMS (ESI) calcd C30H32F6N8O4[M+H]+ m/z 683.25, found 683.25.
To a stirred solution of 2-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy)-N-methyl-N-(1-(5-(trifluoromethyl)pyrimidin-2-yl)piperidin-4-yl) acetamide 3806 (90 mg, 0.13 mmol) in TFA (3 mL) was added TfOH (0.06 mL) at rt. The mixture was stirred at rt for 10 min. The solvent was adjusted to pH 7-8 with saturated NaHCO3 at 0° C. and extracted with DCM. The combined organic phases were washed with water and brine, dried over sodium sulfate, concentrated under vacuum, and purified by C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 47-49) to afford N-methyl-2-(2-(4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy)-N-(1-(5-(trifluoromethyl) pyrimidin-2-yl) piperidin-4-yl) acetamide (mixture of compounds 460 and 461) (50 mg) as a white solid.
Compounds 460 and 461 were separated by SFC (Column: Daicel OJ-H 20 mm I.D.×250 mmL 5 m; Mobile phase: CO2/MeOH=80/20) and concentrated under reduced pressure to afford the first fraction as 460 (17.2 mg, white solid, 99% purity, 100% ee) and the second fraction as 461 (17.2 mg, white solid, 99% purity, 100% ee).
1H NMR (400 MHz, DMSO-d6, ppm) δ:12.99-12.75 (m, 1H), 8.80-8.58 (m, 3H), 5.39-5.15 (m, 1H), 4.88-4.68 (m, 2H), 4.54-4.41 (m, 0.6H), 4.26-4.17 (m, 1H), 4.11-4.06 (m, 1H), 3.87-3.61 (m, 2.4H), 3.04-2.94 (m, 1H), 2.94-2.78 (m, 1H), 2.58 (s, 1H), 1.69-1.41 (m, 7H).
LCMS (ESI) calcd. for C22H24F6N8O3[M+H]+ m/z 563.19, found 563.25.
1H NMR (400 MHz, DMSO-d6, ppm) δ:12.98-12.77 (m, 1H), 8.75-8.64 (m, 3H), 5.32-5.19 (m, 1H), 4.86-4.72 (m, 2H), 4.52-4.42 (m, 0.6H), 4.27-4.17 (m, 1H), 4.12-4.06 (m, 1H), 3.87-3.64 (m, 2.4H), 3.04-2.95 (m, 1H), 2.92-2.81 (m, 1H), 2.58 (s, 1H), 1.71-1.39 (m, 7H).
LCMS (ESI) calcd. for C22H24F6N8O3[M+H]+ m/z 563.19, found 563.25.
To a solution of 2-((benzyloxy)methyl)-4-chloro-5-((2-hydroxyethyl)amino)pyridazin-3(2H)-one 3005 (200 mg, 0.646 mmol) and ethyl (Z)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)but-2-enoate 3902 (186 mg, 0.775 mmol) in t-BuOH (10 mL) was added Pd2(dba)3 (59 mg, 0.0646 mmol), XPhos (154 mg, 0.323 mmol) and K3PO4H2O (445 mg, 1.937 mmol) successively. The mixture was heated at 110° C. in a microwave reactor for 10 minutes under an atmosphere of N2. The resulting solution was evaporated under reduced pressure to obtain a deep brown solid crude which was purified by flash silica chromatography (eluting with PE/EtOAc=50:50 to 0:100) to give 6-((benzyloxy)methyl)-1-(2-hydroxyethyl)-4-methylpyrido[2,3-d]pyridazine-2,5(1H,6H)-dione 3903 (50 mg, 90% purity, 23% yield) as a yellow solid.
LCMS (ESI) calcd for C18H19N3O4 [M+H]+ m/z 342.14, found 342.00.
To a solution of 6-((benzyloxy)methyl)-1-(2-hydroxyethyl)-4-methylpyrido[2,3-d]pyridazine-2,5(1H,6H)-dione 3903 (50 mg, 0.613 mmol) and 1-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-2-yn-1-one (40 mg, 0.1172 mmol) in dry DCM (5 mL) was added P(n-Bu)3 (12 mg, 0.0586 mmol) at rt. The reaction mixture was stirred at rt for 2 h. The reaction solution was concentrated under reduced pressure. The residue was purified by silica gel column (eluting with PE/EtOAc=90:10 to 0:100) to obtain (E)-6-((benzyloxy)methyl)-4-methyl-1-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)pyrido[2,3-d]pyridazine-2,5(1H,6H)-dione 3904 (60 mg, 90% purity, 49% yield) as white solid.
LCMS (ESI) calcd for C30H30F3N7O5[M+H]+ m/z 626.23, found 626.30.
To a solution of (E)-6-((benzyloxy)methyl)-4-methyl-1-(2-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)ethyl)pyrido[2,3-d]pyridazine-2,5(1H,6H)-dione 3904 (60 mg, 0.26 mmol) and 10% Pd/C (6 mg) in EtOAc (15 mL) was stirred at room temperature for 18 h under H2 atmosphere. The resulting solution was filtered through celite, and the filter cake was washed with DCM (5 mL×3). The filtrate was concentrated under reduced pressure to give 6-((benzyloxy)methyl)-4-methyl-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)pyrido[2,3-d]pyridazine-2,5(1H,6H)-dione 3905 (50 mg, 90% purity, 73% yield) as a yellow solid.
LCMS (ESI) calcd for C30H32F3N7O5[M+H]+ m/z 628.24, found 628.15.
A solution of 6-((benzyloxy)methyl)-4-methyl-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)pyrido[2,3-d]pyridazine-2,5(1H,6H)-dione 3905 (50 mg, 0.085 mmol) in TFA (10 mL) was heated at 70° C. for 1 h. The solution was concentrated under reduced pressure to remove most TFA. The residue was diluted with DCM (50 mL) and then adjusted pH to 8 with saturated aqueous NaHCO3 at 0° C. The basified solution was extracted with DCM (10 mL×3). The combined organic layer was washed with brine, dried over Na2SO4, and concentrated under reduced pressure. The crude product was purified by C18 column (mobile phase: ACN-H2O (0.1% FA), gradient: 25%-65%) to obtain 4-methyl-1-(2-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)ethyl)pyrido[2,3-d]pyridazine-2,5(1H,6H)-dione 470 (7.3 mg, 98% purity, 31% yield) as a white solid.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.89 (s, 1H), 8.73 (s, 2H), 8.35 (s, 1H), 6.56 (s, 1H), 4.41 (t, J=5.2 Hz, 2H), 3.86-3.73 (m, 4H), 3.71-3.58 (m, 4H), 3.57-3.42 (m, 4H), 2.56 (s, 3H), 2.53-2.51 (m, 2H).
LCMS (ESI) calcd for C22H24F3N7O4[M+H]+ m/z 508.18, found 508.24.
To a solution of ethyl 2-(3-bromo-4-oxo-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 2707 (1 g, 2.2 mmol) in NMP (20 mL) was added CuI (0.84 g, 4.4 mmol) and HMPA (1.97 g, 11.0 mmol) successively at rt. The reaction mixture was stirred at 130° C. under N2 atmosphere. Methyl 2,2-difluoro-2-(fluorosulfonyl)acetate 4002 (2.1 g, 11.0 mmol) was added dropwise slowly at 130° C. The reaction mixture was stirred at 130° C. for 3 h. The reaction mixture was poured into water and then extracted with EtOAc (100 mL×3). The combined organic layers were washed with brine (100 mL×3), dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=85:15 to 60:40) to afford ethyl 2-(4-oxo-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 4003 (500 mg, 90% purity, 45% yield) as a yellow oil.
LCMS (ESI) calcd for C18H26F3N3O4Si [M−27]+ m/z 406.16, found 406.20.
To a solution of ethyl 2-(4-oxo-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate 4003 (500 mg, 1.15 mmol) in THE (15 mL) was added NaHMDS (1.15 mL, 2.3 mmol, 2 M in THF) at −78° C. under N2 atmosphere. The reaction mixture was stirred at −78° C. for 2 h. The reaction mixture was quenched with D2O (5 mL) at −78° C., the resulting solution was extracted with EtOAc (15 mL×3). The combined organic layers were concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=85:15 to 50:50) to afford ethyl 2-(4-oxo-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate-2-d 4004 (335 mg, 90% purity, 60% yield) as a colorless oil.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 8.60 (s, 1H), 8.26 (s, 1H), 5.47 (s, 2H), 4.25-4.16 (m, 2H), 3.72-3.62 (m, 2H), 1.85 (s, 3H), 1.25-1.21 (m, 3H), 0.93-0.88 (m, 2H), −0.00 (s, 9H).
To a solution of ethyl 2-(4-oxo-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazin-1-yl)propanoate-2-d 4004 (120 mg, 0.28 mmol) in THE (10 mL) was added LiAlH4 (17 mg, 0.41 mmol) at 0° C. The reaction mixture was stirred at 0° C. for 0.5 h. The reaction mixture was quenched with water, the aqueous layer was extracted with EtOAc (20 mL×3). The combined organic layers were concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=85:15 to 20:80) to afford 1-(1-hydroxypropan-2-yl-2-d)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 4005 (85 mg, 90% purity, 60% yield) as a white solid.
LCMS (ESI) calcd for C16H23DF3N3O3Si [M+H]+ m/z 393.16, found 393.19.
To a solution of 1-(1-hydroxypropan-2-yl-2-d)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 4005 (85 mg, 0.22 mmol) in DCM (5 mL) were added 1-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-2-yn-1-one (74 mg, 0.26 mmol) and P(n-Bu)3 (22 mg, 0.11 mmol) at rt. The reaction mixture was stirred at room temperature for 2 h. The reaction mixture was diluted with DCM and water. The aqueous layer was extracted with DCM (10 mL×3). The combined organic layers were dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by flash column chromatography (eluting with PE/EtOAc=20:80 to 0:100) to afford (E)-1-(1-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)propan-2-yl-2-d)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 4006 (135 mg, 90% purity, 83% yield) as a white solid.
LCMS (ESI) calcd for C28H34DF6N7O4Si [M+H]+ m/z 677.25, found 677.15.
A solution of (E)-1-(1-((3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)prop-1-en-1-yl)oxy)propan-2-yl-2-d)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 4006 (130 mg, 0.19 mmol) and Pd/C (15 mg) in MeOH (5 mL) was stirred at rt for 2 h under H2 atmosphere. The resulting solution was filtered through diatomaceous earth and the filter cake was washed with DCM (5 mL×4). The filtrate was concentrated under reduced pressure to obtained 1-(1-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)propan-2-yl-2-d)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 4007 (120 mg, 90% purity, 83% yield) as a white solid.
LCMS (ESI) calcd for C28H36DF6N7O4Si [M+H]+ m/z 679.26, found 679.15.
A solution of 1-(1-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)propan-2-yl-2-d)-3-(trifluoromethyl)-5-((2-(trimethylsilyl)ethoxy)methyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one 4007 (120 mg, 0.18 mmol) in HCl-Dioxane (10 mL, 4 M) was stirred at rt for 6 h. The reaction solution was concentrated under reduced pressure. The residue was purified by C18 column (mobile phase: ACN-H2O (0.1% FA), gradient: 10-95) to give 1-(1-(3-oxo-3-(4-(5-(trifluoromethyl)pyrimidin-2-yl)piperazin-1-yl)propoxy)propan-2-yl-2-d)-3-(trifluoromethyl)-1,5-dihydro-4H-pyrrolo[2,3-d]pyridazin-4-one (mixture of 476 and 477) as a white solid.
Compounds 476 and 477 were separated by SFC (Column: DAICEL OD-H 20 mm I.D.×250 mmL 5 m; Mobile phase: CO2/IPA [0.1% NH3 (7 M Solution in MeOH)]=75/25) and concentrated under reduced pressure to afford the first fraction as 476 (8.1 mg, 99% purity, 100% ee, white solid) and the second fraction as 477 (6.1 mg, 99% purity, 98% ee, white solid).
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.55 (s, 1H), 8.73 (s, 2H), 8.49 (s, 1H), 8.13 (s, 1H), 3.82-3.70 (m, 6H), 3.69-3.55 (m, 2H), 3.53-3.40 (m, 4H), 2.49-2.46 (m, 2H), 1.46 (s, 3H).
LCMS (ESI) calcd for C22H22DF6N7O3 [M+H]+ m/z 549.18 found 549.25.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.55 (s, 1H), 8.72 (s, 2H), 8.49 (s, 1H), 8.13 (s, 1H), 3.83-3.70 (m, 6H), 3.70-3.54 (m, 2H), 3.52-3.41 (m, 4H), 2.49-2.45 (m, 2H), 1.46 (s, 3 H).
LCMS (ESI) calcd for C22H22DF6N7O3 [M+H]+ m/z 549.18 found 549.25.
To a solution of 2-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy)acetic acid 3804 (80 mg, 0.18 mmol) in DCM (4 mL) were added 1-(5-(trifluoromethyl)pyrimidin-2-yl)piperidin-4-amine hydrochloride (78 mg, 0.27 mmol), DIPEA (118 mg, 0.91 mmol), T3P (50% wt in EtOAc, 232 mg, 0.36 mmol) at rt successively. The reaction mixture was stirred at rt for 1 h. The reaction solution was quenched with water (10 mL) and extracted with DCM (15 mL×3). The combined organic phases were concentrated and purified by flash chromatography (eluting with DCM/MeOH=100:0 to 90:10) to afford 2-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl) propoxy)-N-(1-(5-(trifluoromethyl) pyrimidin-2-yl) piperidin-4-yl) acetamide 4101 (70 mg, 90% purity, 51% yield) as a yellow oil.
LCMS (ESI) calcd C29H30F6N8O4[M+H]+m/z 669.23, found 669.15.
To a stirred solution of 2-(2-(5-(4-methoxybenzyl)-4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl)propoxy)-N-(1-(5-(trifluoromethyl) pyrimidin-2-yl) piperidin-4-yl) acetamide 4101 (65 mg, 0.10 mmol) in TFA (3 mL) was added TfOH (0.06 mL) at rt. The mixture was stirred at rt for 10 min. The solvent was adjusted to pH 7-8 with saturated NaHCO3 at 0° C. and then extracted with DCM. The combined organic phases were washed with water and brine, dried over sodium sulfate, concentrated under vacuum, and purified by C18 column (Agela 40 g, mobile phase: ACN-H2O (0.1% FA), gradient: 45-47) to afford 2-(2-(4-oxo-3-(trifluoromethyl)-4,5-dihydro-1H-pyrazolo[3,4-d]pyridazin-1-yl) propoxy)-N-(1-(5-(trifluoromethyl) pyrimidin-2-yl) piperidin-4-yl) acetamide (mixture of 479 and 480) (20 mg, 98% purity, 36% yield) as a white solid.
Compounds 479 and 480 were separated by SFC (Column: Daicel OJ-H 30 mm I.D.×250 mmL 10 m; Mobile phase: CO2/MeOH=80/20) and concentrated under reduced pressure to afford the first fraction as 479 (13.1 mg, white solid, 97% purity, 99% ee) and the second fraction as 480 (9.8 mg, white solid, 98% purity, 100% ee).
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.87 (s, 1H), 8.73 (s, 3H), 8.70 (s, 2H), 7.42 (d, J=8.0 Hz, 1H), 5.34-5.09 (m, 1H), 4.59 (d, J=13.2 Hz, 2H), 4.02-3.73 (m, 5H), 3.13 (t, J=11.8 Hz, 2H), 1.82-1.65 (m, 2H), 1.51 (d, J=6.4 Hz, 3H), 1.40-1.27 (m, 2H).
LCMS (ESI) calcd. for C21H22F6N8O3[M+H]+ m/z 549.17, found 549.24.
1H NMR (400 MHz, DMSO-d6, ppm) δ: 12.87 (s, 1H), 8.73 (s, 1H), 8.70 (s, 2H), 7.42 (d, J=8.0 Hz, 1H), 5.33-5.16 (m, 1H), 4.59 (d, J=13.2 Hz, 2H), 3.95-3.67 (m, 5H), 3.13 (t, J=11.8 Hz, 2H), 1.78-1.63 (m, 2H), 1.51 (d, J=6.8 Hz, 3H), 1.39-1.27 (m, 2H).
LCMS (ESI) calcd. for C21H22F6N8O3[M+H]+ m/z 549.17, found 549.29.
Exemplary compounds of the invention were prepared and tested to determine their effect as PARP7 inhibitors. A typical assay is described below.
Optiplate HB 384-well plates were coated with anti-FLAG antibody, supplied as a 4 mg/ml solution, using a Na2CO3/HCO3 coating buffer at pH 9.6, overnight at 4° C., in order to achieve a final immobilisation per well of 0.3 μg. Wells were then washed 3× in coating wash buffer (PBS/0.05% Tween (v/v)), blocked with 2% BSA (w/v) in coating wash buffer and washed 3 further times prior to assay. For the assay 20 μl of 12.5-37.5 nM recombinant human Flag-tagged PARP7 (amino acids 456-657) was added to each well of the 384-well plate for 30 min at room temperature. 50 nl of test compound in DMSO was added using pintool technology and plates were incubated for a further 30 min at room temperature. 5 μl of 15 μM biotin-NAD+ assay solution in 20 mM HEPES (pH 7.5), 100 mM NaCl, 2 mM DTT, 0.1% BSA (w/v), 0.02% Tween (v/v) assay buffer was then added and MARylation proceeded for 2-3 h at room temperature prior to the addition of 5 μl of 12 mM NAD+ quenching solution. After 30 min at room temperature, assay solution was removed and following washing 5 times, 100 μl of a 1:1000 dilution of DELFIA Eu-N1 Streptavidin reagent was added. Plates were then incubated for 30 min at room temperature. Reaction mixture was removed and plates washed 5 times prior to the addition of 25 μl DELFIA enhancement solution. Following incubation for 30 min at room temperature, fluorescence was read on either an Envision or Pherastar FS (Ex337 nm, Em620 nm).
Typically compounds were tested from 10-20 μM at 0.5 log intervals in 10-12-point concentration-response curves to determine IC50 values. Data was analysed using ActivityBase software and replicate values for the low (without enzyme, 0.2% DMSO) and high (0.2% DMSO) % controls were averaged and the data obtained from the test compounds expressed as a % of 100% using the below formulae:
% activity=100*(value−low control)/(high control−low control)
The IC50 values for a variety of test compounds are shown in Table 1.
Selected compounds were also tested for their ability to induce type I interferon (interferon β, IFNβ) production in cancer cells as a cell-based measure of PARP7 inhibition and its effects on stimulating the STING pathway signalling.
A particularly suitable assay to measure IFNβ from mouse cancer cell supernatants is described below.
CT26 and MC38 cells were seeded in 96-well microplates each at a density of 30,000 cells per well. Following overnight incubation, cells were treated with either DMSO, 10 μM compound 177, or various chemotherapeutic agents (final DMSO concentration of 0.2% v/v). Cells were also treated with 10 μM compound 177 in combination with various chemotherapeutic agents. After 24 hours, IFNβ was measured from cell supernatants using a sandwich enzyme linked immunosorbent assay (ELISA) assay kit (PBL Assay Sciences, catalogue number 42410-2) according to manufacturer's instructions.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2104664.4 | Mar 2021 | GB | national |
| 2114315.1 | Oct 2021 | GB | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2022/058490 | 3/30/2022 | WO |
