This invention relates to unsolvated and host-guest solvated crystalline forms of (2E,4S)-4-[(N-{[(2R)-1-isopropylpiperidin-2-yl]-carbonyl}-3-methyl-L-valyl)(methyl)amino]-2,5-dimethylhex-2-enoic acid, E7974. E7974 possesses therapeutic efficacy for the treatment of various cancers, inflammatory disorders, autoimmune disorders, and proliferative disorders as well as for the treatment and prevention of restenosis in blood vessels.
Hemiasterlin (1) was first isolated from the sponge Hemiasterella minor (class, Demospongiae; order, Hadromedidia; family, Hemiasterellidae) collected in Sodwana Bay, South Africa (see, Kashman et al. U.S. Pat. No. 5,661,175). Hemiasterlin exhibits antitumor activity against several cell lines, including human lung carcinoma, human colon carcinoma and human melanoma.
After the initial isolation and reporting of this compound, additional hemiasterlins were isolated, and several hemiasterlin derivatives were synthesized and their biological activity was also investigated. It was subsequently reported that Hemiasterlin and certain analogs thereof exhibit antimitotic activity and thus are useful for the treatment of certain cancers (see, U.S. Pat. No. 6,153,590 and PCT application WO 99/32509).
U.S. published patent application, U.S. 20040229819 A1, (which is incorporated herein by reference) discloses a number of hemiasterlin analogs and their uses. One such analog, (2E,4S)-4-[(N-{[(2R)-1-isopropylpiperidin-2-yl]-carbonyl}-3-methyl-L-valyl)(methyl)amino]-2,5-dimethylhex-2-enoic acid, E7974, possesses therapeutic activity in the treatment of various cancers, lymphoma, leukemia and multiple myeloma as well as in the treatment and prevention of restenosis of blood vessels. The synthesis of E7974 is described in Example 14 of U.S. 20040229819-A1, which identifies the compound as E807974. Example 14 reports the preparation of ER-807974 as thick oil free-base compound, not as crystalline E7974.
Although therapeutic efficacy is the primary concern for a therapeutic agent, like E7974, the salt and crystal form of a drug candidate can be critical to its development. Each salt or each crystalline form (polymorph) of a drug candidate can have different solid state (physical and chemical) properties, for example, solubility, stability, or the ability to be reproduced. These properties can impact the selection of a compound as an active pharmaceutical ingredient (API), the ultimate pharmaceutical dosage form, the optimization of manufacturing processes, and absorption in the body. Moreover, finding the most adequate form for further drug development can reduce the time and the cost of that development.
Obtaining pure crystalline forms is extremely useful in drug development. It permits better characterization of the drug candidate's chemical and physical properties. Crystalline forms often have better chemical and physical properties than the amorphous state. The crystalline form may possess more favorable pharmacology than the amorphous form or be easier to process. It may also have better storage stability.
One such physical property, which can affect processability, is the flowability of the solid, before and after milling. Flowability affects the ease with which the material is handled during processing into a pharmaceutical composition. When particles of the powdered compound do not flow past each other easily, a formulation specialist must take that fact into account in developing a tablet or capsule formulation, which may necessitate the use of glidants such as colloidal silicon dioxide, talc, starch or tribasic calcium phosphate. Another important solid state property of a pharmaceutical compound is its dissolution rate in aqueous fluid. The rate of dissolution of an active ingredient in a patient's stomach fluid may have therapeutic consequences since it impacts the rate at which an orally-administered active ingredient may reach the patient's bloodstream.
These practical physical properties are influenced by the solid state form of a compound, e.g., the conformation and orientation of molecules in the unit cell of the crystalline compound, or whether or not a molecule associates with solvent molecules to form a solvate. The ability of a molecule to adopt a different conformation and/or arrangement of molecules in the crystal lattice is called polymorphism. The crystalline (or polymorphic) form or solvate often has thermal behavior different from the amorphous material, another polymorphic form, or a solvate. Thermal behavior is measured in the laboratory by such techniques as capillary melting point, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) and may be used to distinguish some polymorphic forms from others. A crystalline form or a particular polymorphic form generally possesses distinct crystallographic and spectroscopic properties detectable by powder X-ray diffraction (PXRD), single crystal X-ray crystallography, solid state NMR spectroscopy, e.g. 13C CP/MAS NMR, infrared spectrometry among other techniques.
The invention relates to crystalline forms of (2E,4S)-4-[(N-{[(2R)-1-isopropylpiperidin-2-yl]-carbonyl}-3-methyl-L-valyl)(methyl)amino]-2,5-dimethylhex-2-enoic acid, E7974. E7974 has two unsolvated crystalline forms, M1 and O1. These crystalline forms, along with another form, M2, can also form crystalline host-guest solvates where the solvent is present in cavities channels, or other void spaces within the crystal lattice. As used here, the terms cavity and/or void space also refers to channels.
The invention also relates to the therapeutic uses of the crystalline forms of E7974. Accordingly, a pharmaceutical composition containing a crystalline form of E7974 and a pharmaceutically acceptable carrier represents one embodiment of the invention. The invention further relates to methods for treating a cancer, an inflammatory disorder, an autoimmune disorder, or a proliferative disorder comprising the step of administering to a patient in need thereof a therapeutically effective amount of a crystalline form of E7974. The crystalline forms of E7974 may be administered by itself or as a pharmaceutical composition of the invention.
(2E,4S)-4-[(N-{[(2R)-1-isopropylpiperidin-2-yl]carbonyl}-3-methyl-L-valyl)(methyl)amino]-2,5-dimethylhex-2-enoic acid (IUPAC nomenclature), E7974, has the following chemical formula (2).
The CAS chemical name for E7974 is 2-Hexenoic acid, 4-[[(2S)-3,3-dimethyl-2-[[[(2R)-1-(1-methylethyl)-2-piperidinyl]carbonyl]amino]-1-oxobutyl]methylamino]-2,5-dimethyl 2E,4S). Its CAS Registry Number is 610787-07-0. E7974 is the zwitterionic form of the compound.
E7974 is useful as a therapeutic agent for the treatment of various cancers, inflammatory disorders, autoimmune disorders, and proliferative disorders. More specifically, E7974 can be used for the treatment of diseases and disorders including, but not limited to prostate, breast, colon, bladder, cervical, skin, testicular, kidney, ovarian, stomach, brain, liver, pancreatic and esophageal cancer, lymphoma, leukemia and multiple myeloma. The chemical synthesis and anti-tumor activity of E7974 were the subject of three posters presented at the 96th Annual Meeting of the American Association for Cancer Research (AACR), Apr. 16-20, 2005, Anaheim, Calif.: 1) Tubulin-based Antimitotic Mechanism of Novel Hemiasterlin Analog E7974, G. Kuznetsov et al., Abstract No. 3436; 2) Synthetic Analogs of the Natural Marine Product Hemiasterlin: Optimization and Discovery of E7974, a Novel and Potent Anti-tumor Agent, J. Kowalczyk et al., Abstract No. 1212; and 3) In vitro and in vivo antitumor activities of novel hemiasterlin analog E7974, G. Kuznetsov et al., Abstract No. 3432. E7974 can also be used to treat and prevent restenosis of blood vessels subject to traumas such as angioplasty and stenting.
This invention relates to crystalline forms of E7974, unsolvated crystalline forms and host-guest solvates of those crystalline forms. Unless a specific form designation is given, the term “crystalline E7974” refers to all crystalline forms of E7974 described here. There are two monoclinic crystalline forms, M1 and M2 and one orthorhombic crystalline form, O1. The M1 and O1 crystalline forms exist as unsolvated crystalline forms. Each of these is described below. The space group designations, monoclinic and orthorhombic, generally refer to the host crystal space group. Upon solution, the specific group of the host-guest soluate may change somewhat and be substantially the same as that of the host.
The M1, M2 and O1 crystalline forms have the ability to incorporate solvent molecules into their crystal lattices without losing crystallinity. These solvates are “host-guest” in that the solvent is incorporated into a cavity, (also called a void space or channel) in the crystalline E7974 lattice.
Crystalline E7974-form M1 is prepared by crystallizing crude E7974 in acetonitrile with heating up to reflux and then slowly cooling to allow crystal formation. In a preferred method, crude E7974 may be first crystallized from acetonitrile at room temperature, preferably 25° C., and then recrystallizing in acetonitrile with heating to reflux and slow cooling. Drying solvated forms of crystalline form M1 also yields the unsolvated crystalline form M1.
Crystalline E7974-form M1 possesses superior processability, purification controls (by recrystallization), and solid-state stability. As described below in the Examples and shown in the Figures, crystalline E7974-form M1 was characterized by X-ray powder diffraction (XRD), single crystal X-ray diffraction, infrared spectroscopy, solid state 13C NMR, thermal analyses and hygroscopicity measurements.
Crystalline E 7974-form O1 is a second unsolvated crystal form of E7974. As discussed below, form O1 is prepared by dissolving E7974 in various solvents and then drying the resulting crystalline solid to remove the solvent and yield the unsolvated form O1. The Examples and Figures below characterize form O1 using X-ray powder diffraction (XRD), single crystal X-ray diffraction, infrared spectroscopy, solid state 13C NMR spectroscopy, thermal analyses and hygroscopicity measurements. The approximate size of the cavity was calculated using a virtual solvent-free structure (crystalline E7974-O1-nitrobenzene by excluding the nitrobenzene molecules from the crystal structure and keeping the unit cell parameters unmodified). The Volume of the Total Potential Solvent Area is 936.2 Å3 versus a unit cell volume of 3260.3 Å3, which means that 28.7% of the unit cell volume of O1 form simulated solvent-free structure should be accessible for solvent molecules.
Crystalline forms of E7974 of the invention contain cavities, channels or void spaces (all of which are referred to here as cavities), in the crystal structure and form solvated crystalline forms as “host-guest solvates” in which solvent molecules are present within the cavities. These crystalline forms of E7974 form host-guest solvates with organic solvents. The solvent may be present in a stoichiometric amount or a non-stoichiometric amount. A “non-stoichiometric solvate” is one where different preparation methods or processing of the material result in a non-discrete (or continuous) change in the solvent stoichiometry relative to the E7974 molecules in the crystal. Some crystalline forms of the invention have cavities which may contain organic solvent molecules. Both forms M1 and O1 form host-guest solvates. In addition, another monoclinic crystalline form, M2, exists as a host-guest solvated form.
There is no particular limitation on the organic solvent which may be solvated within the cavity of the crystalline E7974, other than that the host-guest solvate be a crystalline solid. The organic solvent may be a single solvent, a mixture of organic solvents, or an aqueous mixture containing the organic solvent(s). The solvent is typically the solvent used to manufacture crystalline E7974 or a pharmaceutical composition containing E7974. Accordingly the organic solvent forming the host-guest solvate is often one used in the synthesis or purification of E7974, which may be advantageous for the process. Drying the host-guest solvate yields the unsolvated form or, in the case of solvated form M2, the unsolvated form M1. The crystalline host-guest solvates of the invention may exist as mixtures of forms, including mixtures of solvated and unsolvated forms.
Suitable solvents used to form host-guest solvates include, but are not limited to, 1,4-dioxane; 1-bromopropane; 1-bitropropane; 2-butoxyethyl acetate; acetone, acetonitrile; amyl ether; chlorobenzene; chloroform, cyclohexanone; dichloromethane (DCM); diisobutyl ketone; diisopropylether; N1N-dimethylacetamid (DMA); dimethylformamide (DMF); ethylacetate/n-heptane (50:50); ethylacetate; isophorone; methyl isobutyl ketone (MIBK); n-butylacetate; nitrobenzene; nitromethane; t-butyl methylether (TBME); 2,2,2-trifluroethenol
A pharmaceutical composition of the invention may be any pharmaceutical form which contains one of the crystalline forms of E7974. The pharmaceutical composition may be a solid form, a liquid suspension, an injectable composition, a topical form, or a transdermal form. These pharmaceutical forms are disclosed in U.S. 20040229819 A1, which is incorporated here by reference.
Depending on the type of pharmaceutical composition, the pharmaceutically acceptable carrier may be chosen from any one or a combination of carriers known in the art. The choice of the pharmaceutically acceptable carrier depends upon the pharmaceutical form and the desired method of administration to be used. For a solid pharmaceutical composition of the invention, that is one having a crystalline form of E7974, a carrier should be chosen that maintains the particular crystalline form of E7974 used. In other words, for solid pharmaceutical compositions the carrier should not substantially alter the crystalline form of E7974. Nor should the carrier be incompatible with E7974, such as by producing any undesirable biological effect or otherwise interacting in a deleterious manner with any other component(s) of the pharmaceutical composition.
The pharmaceutical compositions of the invention are preferably formulated in unit dosage form for ease of administration and uniformity of dosage. A “unit dosage form” refers to a physically discrete unit of therapeutic agent appropriate for the patient to be treated. It will be understood, however, that the total daily dosage of E7974 and its pharmaceutical compositions according to the invention will be decided by the attending physician within the scope of sound medical judgment.
Because the crystalline forms of E7974 are more easily maintained during their preparation, solid dosage forms are a preferred form for the pharmaceutical composition of the invention. Solid dosage forms for oral administration, such as capsules, tablets, pills, powders, and granules, are particularly preferred. In such solid dosage forms, the active compound is mixed with at least one inert, pharmaceutically acceptable carrier such as sodium citrate or dicalcium phosphate. The solid dosage form may also include one or more of: a) fillers or extenders such as starches, lactose, sucrose, glucose, mannitol, and silicic acid; b) binders such as, for example, carboxymethylcellulose, alginates, gelatin, polyvinylpyrrolidinone, sucrose, and acacia; c) humectants such as glycerol; d) disintegrating agents such as agar-agar, calcium carbonate, potato or tapioca starch, alginic acid, certain silicates, and sodium carbonate; e) dissolution retarding agents such as paraffin; f) absorption accelerators such as quaternary ammonium compounds; g) wetting agents such as, for (TFE); tetrahydrofuron (THF); toluene; trichloroethylene; trifluomethane toluene; water/2-propanol (10:90); water/2-propanol (20:80); water/acetone (10:90); water/acetone (20:80); water/acetonitrile (10:90); water/ethanol (10:90); and water/ethanol (20:80). It is generally preferred that the organic solvent is a pharmaceutically acceptable solvent. Preferred organic solvents for host-guest solvates of crystalline E7974-form M1 are the acetone and acetonitrile solvates. For host-guest solvate of crystalline E7974-form M2, the following solvents are preferred: 1,4-dioxane, ethylacetate/n-heptane (50:50), acetone, and nitromethane. The preferred solvents for the host-guest solvates of crystalline E7974-form O1 are toluene, water/ethanol (10:90), TBME, and nitrobenzene.
The invention relates to pharmaceutical compositions comprising a therapeutically effective amount of a crystalline form of E7974 and a pharmaceutically acceptable carrier. As discussed above, E7974 possesses biological properties making it useful for the treatment of cancer, inflammatory, autoimmune, and/or proliferative diseases and disorders as well as the treatment and prevention of restenosis in blood vessels. Pharmaceutical compositions for the treatment of those diseases and disorders contain a therapeutically effective amount of a crystalline form of E7974 as appropriate for treatment of a patient with the particular disease or disorder.
A “therapeutically effective amount” of E7974 in a crystalline form of the invention (discussed here concerning the pharmaceutical compositions and below concerning the methods of treatment according to the invention) refers to an amount sufficient to reduce the effects of an inflammatory or autoimmune response or disorder; an amount sufficient to prevent, kill, or inhibit the growth or speed of tumor cells; or an amount sufficient to treat or prevent restenosis of blood vessels. The actual amount required for treatment of any particular patient will depend upon a variety of factors including the disorder being treated and its severity; the specific pharmaceutical composition employed; the age, body weight, general health, sex and diet of the patient; the mode of administration; the time of administration; the route of administration; and the rate of excretion of E7974; the duration of the treatment; any drugs used in combination or coincidental with the specific compound employed; and other such factors well known in the medical arts. These factors are discussed in Goodman and Gilman's “The Pharmacological Basis of Therapeutics”, Tenth Edition, A. Gilman, J. Hardman and L. Limbird, eds., McGraw-Hill Press, 155-173, 2001, which is incorporated herein by reference.
example, cetyl alcohol and glycerol monostearate; h) absorbents such as kaolin and bentonite clay; and i) lubricants such as talc, calcium stearate, magnesium stearate, solid polyethylene glycols, sodium lauryl sulfate. The solid dosage forms may also comprise buffering agents. They may optionally contain opacifying agents and can also be of a composition that they release the active ingredient(s) only, or preferentially, in a certain part of the intestinal tract, optionally, in a delayed manner Remington's Pharmaceutical Sciences, Sixteenth Edition, E. W. Martin (Mack Publishing Co., Easton, Pa., 1980) discloses various carriers used in formulating pharmaceutical compositions and known techniques for the preparation thereof. Solid dosage forms of pharmaceutical compositions of the invention can also be prepared with coatings and shells such as enteric coatings and other coatings well known in the pharmaceutical formulating art.
Crystalline E7974 can be in a solid micro-encapsulated form with one or more carriers as discussed above. Microencapsulated forms of crystalline forms of E7974 may also be used in soft and hard-filled gelatin capsules with excipients such as lactose or milk sugar as well as high molecular weight polyethylene glycols and the like.
Liquid dosage forms for oral administration include, but are not limited to, pharmaceutically acceptable emulsions, microemulsions, solutions, suspensions, syrups and elixirs. In addition to the active compounds, the liquid dosage forms may contain inert diluents commonly used in the art such as, for example, water or other solvents, solubilizing agents and emulsifiers such as ethyl alcohol, isopropyl alcohol, ethyl carbonate, ethyl acetate, benzyl alcohol, benzyl benzoate, propylene glycol, 1,3-butylene glycol, dimethylformamide, oils (in particular, cottonseed, groundnut, corn, germ, olive, castor, and sesame oils), glycerol, tetrahydrofurfuryl alcohol, polyethylene glycols and fatty acid esters of sorbitan, and mixtures thereof. Besides inert diluents, the oral compositions can also include adjuvants such as wetting agents, emulsifying and suspending agents, sweetening, flavoring, and perfuming agents.
Injectable preparations, for example, sterile injectable aqueous or oleaginous suspensions may be formulated according to the known art using suitable dispersing or wetting agents and suspending agents. The sterile injectable preparation may also be a sterile injectable solution, suspension or emulsion in a nontoxic parenterally acceptable diluent or solvent, for example, as a solution in 1,3-butanediol. Among the acceptable vehicles and solvents that may be employed are water, Ringer's solution, U.S.P. and isotonic sodium chloride solution. In addition, sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose any bland fixed oil can be employed including synthetic mono- or diglycerides. In addition, fatty acids such as oleic acid are used in the preparation of injectables.
The injectable formulations can be sterilized, for example, by filtration through a bacterial-retaining filter, or by incorporating sterilizing agents in the form of sterile solid compositions which can be dissolved or dispersed in sterile water or other sterile injectable medium prior to use.
In order to prolong the effect of a drug, it is often desirable to slow the absorption of the drug from subcutaneous or intramuscular injection. This may be accomplished by the use of a liquid suspension, by the use of a crystalline form, or by the use of an amorphous material with poor water solubility. The rate of absorption of the drug then depends upon its rate of dissolution that, in turn, may depend upon crystal size and crystalline form. Alternatively, delayed absorption of a parenterally administered drug form is accomplished by dissolving or suspending the drug in an oil vehicle. Injectable depot forms are made by forming microencapsule matrices of the drug in biodegradable polymers such as polylactide-polyglycolide. Depending upon the ratio of drug to polymer and the nature of the particular polymer employed, the rate of drug release can be controlled. Examples of other biodegradable polymers include (poly(orthoesters) and poly(anhydrides)). Depot injectable formulations are also prepared by entrapping the drug in liposomes or microemulsions which are compatible with body tissues.
Compositions for rectal or vaginal administration are preferably suppositories which can be prepared by mixing the compounds of this invention with suitable non-irritating excipients or carriers such as cocoa butter, polyethylene glycol or a suppository wax which are solid at ambient temperature but liquid at body temperature and therefore melt in the rectum or vaginal cavity and release E7974.
Crystalline forms of E7974 according to the invention may also be used to formulate or be formulated in an autoclavable liquid formulation. Exemplary aqueous development formulations (1 mg/ml E7974) include 1) isotonic 5% dextrose, 20 mM citrate buffer, pH 4.5; 2) non-isotonic, 20 mM citrate buffer, pH 4.5; and 3) 0.9% NaCl, 20 mM phosphate buffer, pH 7. All three autoclaved formulations show good storage stability.
The invention also provides methods for and the use of crystalline E7974 in the treatment of proliferative disorders, inflammatory or autoimmune disorders, as well as to treat or prevent restenosis of blood vessels. Proliferative disorders include cancers, such as colorectal cancer, glioblastoma multiforme (GBM), breast, prostate, non-small cell lung cancer, esophageal/gastic cancer and hepatocellular cancers or tumors. Some tumors may be resistant to certain drugs, such as multi-drug resistant, or taxane-resistant tumors. Crystalline E7974 and pharmaceutical compositions containing it may, according to the invention, be administered using any amount, any form of pharmaceutical composition and any route of administration effective for the treatment. After formulation with an appropriate pharmaceutically acceptable carrier in a desired dosage, the pharmaceutical compositions of this invention can be administered to humans and other animals orally, rectally, parenterally, intraveneously, intracistemally, intravaginally, intraperitoneally, topically (as by powders, ointments, or drops), bucally, as an oral or nasal spray, or the like, depending on the location and severity of the condition being treated. In certain embodiments, crystalline forms of E7974 according to the invention may be administered at dosage levels of about 0.001 mg/kg to about 50 mg/kg, from about 0.01 mg/kg to about 25 mg/kg, or from about 0.1 mg/kg to about 10 mg/kg of subject body weight per day, one or more times a day, to obtain the desired therapeutic effect. It will also be appreciated that dosages smaller than 0.001 mg/kg or greater than 50 mg/kg (for example 50-100 mg/kg) can be administered to a subject. Crystalline forms of the invention may be administered alone or in combination with other active agents such as anti-cancer agents including anthracyclines, gemcitabine, cisplatin, carboplatin, doctaxel, or a combination of active agents. The combination may be in the form of a composition of the invention comprising one, two or more additional active agents. Alternatively, the additional active agents may be administered separately, before, during or after administration of a composition of the invention. Thus, the various crystalline forms of the invention may be used in the manufacture of a medicament for the treatment of proliferative disorder including cancer, an inflammatory or autoimmune disorder, or restenosis.
To prepare crystalline E7974-form M1
Crystalline E7974-from M1
Crystalline E7974-form M1 was characterized by powder X-ray diffraction (PXRD). Crystalline E7974-form M1 powder was placed on the sample platform of an X-ray powder diffractometer (RINT-2000, Rigaku, Japan) and analyzed under the conditions shown in Table 1.
Table 3 identifies the peaks in the PXRD pattern in
Solid-state characterization of crystalline E7974-form M1
13C CP/MAS NMR spectra were acquired at 100.6 MHz for 13C using a Varian NMR spectrometer equipped with a Varian 7 mm CPMAS probe. All equipment was thoroughly cleaned before packing and unpacking each sample. A sample of crystalline E7974-form M1
In general, these preferred peaks can be observed in the solid-state 13C NMR spectrum of an intact tablet without significant overlap from other peaks. The reason is that many common excipients, which are the ingredients added to the active pharmaceutical ingredient (API) to make the pharmaceutical tablet composition, will also show up in the solid-state 13C NMR spectrum. Given their chemical nature, the resonances for these excipients generally appear between 50 and 110 ppm in the 13C-NMR spectrum. The excipient peaks can be significantly more intense than the peaks from the API if the tablet composition is dominated by excipients. For this reason the preferred range in the solid-state 13C NMR spectra to identify and compare peaks from a crystalline E7974-form M1
The solid-state stability of crystalline E7974-form M1
1Three preparations were prepared at each condition and the averages of the results are listed here.
2Light shielded sample stored at −20° C. was used as control for weight/weight analyses.
3Sum of all impurities >0.05% as determined by HPLC area-%.
4Sample solutions received 6.8 million lux-hours visible light irradiation. ICH guidelines, recommend samples receive no less than 1.2 million lux-hours visible light irradiation for regulated drug product stability filings.
The following procedure may be used to prepare solvated crystalline forms of E7974 M1, M2, and O1. Forms M2
10) The filtered solid is partially dried under nitrogen flow for 30 to 60 min.
1Dissolution should be observed from 63° C. to 70° C.
2Sample was not dissolved after 1 h at 75° C.
Observations: Recovery yield for toluene crystallization (entry 3) was 92%. Mediocre to poor recovery was observed from 1,4-dioxane or nitromethane. Solution turned yellow when it was heated >100° C. for 15 min., possible indication of decomposition.
*Qualitative crystallinity was established by visual inspection of the PXRD patterns
Unsolvated crystalline E7974 forms M1 and O1 may be prepared by drying the host-guest crystalline solvates. The solvated product is fully dried under high vacuum at 25° C. to constant weight. A sample of the dried product is analyzed by PXRD to confirm the crystal form (M1
High throughput crystallization studies were performed using crystalline E7974-form M1 as the starting material. The 96-well plates were divided into two parts in which each part contained a different concentration of starting material in solvent: 50 mg/ml (columns A to F) and 100 mg/ml (columns G to L) (see Table 9). A stock solution of E7974 in methanol (100 mg/ml) was used for dosing the starting material in the well plates (20 μL for the low concentration wells, 5% w/v, and 40 μL for the high concentration wells, 10% w/v). The plates containing the stock solution were placed in a vacuum chamber (1.3 kPa) at room temperature for 48 h. After the stock solvent was evaporated different solvents were added and each well was individually sealed. The 96-well plates containing E7974 and crystallization solvents were subjected to a series of temperature profiles as shown in
Table 11 lists the solvents which gave crystalline forms of E7974 in the high throughput crystalization studies. The crystalline forms could generally be observed by visual inspection but was determined by powder X-ray diffraction (PXRD). PXRD analysis also showed amorphous E7974 in some wells. The amorphous form is not reported here.
High Throughput PXRD Analysis of Crystalline Forms
After the crystallization experiments and the solvent evaporation the crystalline products were harvested. PXRD patterns were obtained using a high throughput PXRD set-up. The plates were mounted on a Bruker GADDS diffractometer that is equipped with a Hi-Star area detector. The PXRD platform is calibrated using Silver Behenate for the long d-spacings and Corundum for the short d-spacings. The data collection was carried out at room temperature using monochromatic CuKα radiation in the region of 2Θ between 1.5 and 41.5°. The diffraction pattern of each well was collected in two 2Θ ranges (1.5≦2Θ≦21.5° for the 1st frame, and 19.5≦2Θ≦41.5° for the second frame) with an exposure time of 90 s for each frame. The carrier material used during PXRD analysis of most samples was transparent to X-rays and contributed only slightly to the background. No background subtraction or curve smoothing was applied to the PXRD patterns.
Single Crystal Structure Determination
Suitable single crystals from the high throughput studies were selected and glued to a glass fibre, which is mounted on a X-ray diffraction goniometer. X-ray diffraction data are collected for the mounted crystals at a temperature of 233 K using a KappaCCD system and MoKα radiation generated by a FR590 X-ray generator (Bruker Nonius, Delft, The Netherlands). Unit-cell parameters and crystal structure are determined and refined using the software package maXus (Mackay et al., 1997). From the crystal structure the theoretical X-ray powder diffraction pattern can be calculated using PowderCell for Windows version 2.3 (Kraus et al., 1999).
Single Crystal structure of form M2
The crystal structure of crystalline form M2
w = 1/[¥s{circumflex over ( )}2{circumflex over ( )}(Fo{circumflex over ( )}2{circumflex over ( )}) + (0.1000P){circumflex over ( )}2{circumflex over ( )}] where P = (Fo{circumflex over ( )}2{circumflex over ( )} + 2Fc{circumflex over ( )}2{circumflex over ( )})/3
Crystal structure of crystalline E7974 form O1
The crystal structure of crystalline E7974 form O1_nitrobenzene was determined from the single-crystal data collected from the material obtained after the crystallization experiment with nitrobenzene (prepared according to plate 003, high concentration, crystallization temperature 5° C.). The PXRD analysis indicated that the material was a mixture forms M2
Single crystal analyses were also performed for O1 forms obtained from nitrobenzene at 25° C. crystallization temperature and host-guest solvated form O1 obtained from TBME.
Characterization of Crystalline, Host-guest Solvate E7974-form M2
1A larger degree of uncertainty is given due to the breadth of the peaks.
The infrared spectrum of crystalline E7974-form M2
The PXRD pattern, and IR spectrum data was acquired using the techniques and equipment described in Examples 9 and 3, respectively. The 13C CP/MAS NMR spectrum was obtained as described in Example 5. The DSC data was acquired using the procedure described in Example 4 using a 1.79 g sample.
Crystalline E7974 form O1
The infrared spectrum of crystalline E7974-form O1
The PXRD pattern and IR spectrum were acquired using the techniques and equipment described in Example 3. The DSC data was acquired using the procedure described in Example 4 using a 3.75 g sample.
The infrared spectrum of crystalline E7974-form O—
This application claims priority under 35 U.S.C. § 119 to provisional application Ser. No. 60/677,811, which is incorporated herein by reference.
Number | Date | Country | |
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60677811 | May 2005 | US |