The invention relates to compounds of the formula I
R-Q-X I
Similar cyclic peptide compounds are disclosed in DE 43 10 643 and DE 195 38 741.
The compound cyclo-(Art-Gly-Asp-Glu(ε-Ahx-Cys-NH2)-D-Val) is disclosed by D. Delforge et al. in Anal. Biochem. 242, 180-186 (1996).
The invention is based on the object of finding novel compounds having valuable properties, in particular those which can be used for the production of medicaments.
It has been found that the compounds of the formula I and their salts have very valuable pharmacological properties together with good tolerability. They act especially as integrin inhibitors, where they inhibit, in particular, the interactions of the αv-, or β3- or β5-integrin receptors with ligands, such as, for example, the binding of fibrinogen to the β3-integrin receptor. The compounds show particular activity in the case of the integrins αvβ3, αvβ5, αIIbβ3 and also αvβ1, αvβ6 and αvβ8.
This action can be demonstrated, for example, by the method which is described by J. W. Smith et al. in J. Biol. Chem. 265, 12267-12271 (1990).
The dependence of the origin of angiogenesis on the interaction between vascular integrins and extra-cellular matrix proteins is described by P. C. Brooks, R. A. Clark and D. A. Cheresh in Science 264, 569-71 (1994).
The possibility of the inhibition of this interaction and thus for the initiation of apoptosis (programmed cell death) of angiogenic vascular cells by a cyclic peptide is described by P. C. Brooks, A. M. Montgomery, M. Rosenfeld, R. A. Reisfeld, T.-Hu, G. Klier and D. A. Cheresh in Cell 79, 1157-64 (1994).
Compounds of the formula I which block the interaction of integrin receptors and ligands, such as, for example, of fibrinogen on the fibrinogen receptor (glycoprotein IIb/IIIa), prevent, as GPIIb/IIIa antagonists, the spread of tumour cells by metastasis. This is confirmed by the following observations:
The spread of tumour cells from a local tumour into the vascular system takes place by means of the formation of microaggregates (microthrombi) by interaction of the tumour cells with blood platelets. The tumour cells are screened by the protection in the microaggregates and are not recognized by the cells of the immune system. The microaggregates can collect on vascular walls, whereby further penetration of tumour cells into the tissue is facilitated. Since the formation of the microthrombi is mediated by fibrinogen binding to the fibrinogen receptors on activated blood platelets, the GPIIa/IIIb antagonists can be regarded as efficacious metastasis inhibitors.
The (meth)acrylate radical serves to bond the peptides covalently to biocompatible surfaces of, for example, implants which have free acrylate or methacrylate radicals, such as, for example, poly(methyl methacrylate) moulded articles (bone cements) or acrylate- and methacrylate-containing layers, for example on metal surfaces.
Correspondingly, the thiol radical serves for peptide bonding, for example, to gold surfaces.
The invention therefore relates in particular to the compounds of the formula I for covalent bonding via the functional group of the radical X to biocompatible surfaces.
If X═—NH—(CH2)p—SR10, the functional group which bonds to the surface is the SH radical, i.e. if R10═H.
The peptides according to the invention now make possible the biofunctionalization of biomaterials, in particular implants for all conceivable organs, by coating thereof, mainly the adhesion of those cell species being stimulated which in each case are intended to accomplish the tissue integration of the appropriate biomaterial. Using such coatings an accelerated and increased integration of various biomaterials/implants with improved long-term stability can be achieved after introduction thereof into the body.
In this connection, reference is made to the second application filed on the same date by the Applicant, in which suitable biomaterials and the coating thereof with the compounds according to the invention are described.
The peptides according to the invention bind selectively to integrins. After immobilization on biocompatible surfaces, e.g. implants, they stimulate the adhesion of cells which carry integrins. After coating of the compounds on the surfaces, those cell species can be selectively stimulated to bind which are also intended to accomplish the implant integration into the natural tissue after implantation. Thus, for example, osteoblasts, osteoclasts and endothelial cells are αv-carrying cell species.
The invention therefore relates to the compounds of the formula I as integrin inhibitors for selective cell enrichment on implants.
After anchorage to a biocompatible surface, the compounds of the formula I can be employed as medicaments in human and veterinary medicine, in particular they can be employed as integrin inhibitors for the treatment of disorders, defects and inflammations caused by implants, such as inadequate and delayed integration of biomaterials and implants, of thrombosis caused by implants, of bone and tooth defects, and also of osteolytic disorders such as osteoporosis, thrombosis, cardiac infarct, arteriosclerosis, in wound healing for assisting the healing process, and also for the acceleration and reinforcement of the integration process of the implant or of the biocompatible surface into the tissue.
The compounds of the formula I can be employed as antimicrobially active substances in operations where biomaterials, implants, catheters or heart pacemakers are used. They have an antiseptic action here. The efficacy of the antimicrobial activity can be demonstrated by the procedure described by P. Valentin-Weigund et al., in Infection and Immunity, 2851-285.5 (1988).
The invention thus relates to the compounds of the formula I as integrin inhibitors for the treatment of disorders caused by implants, defects, inflammations and of osteolytic disorders such as osteoporosis, thrombosis, cardiac infarct and arteriosclerosis, and also for the acceleration and reinforcement of the integration process of the implant or of the biocompatible surface into the tissue.
The invention further relates to the use of compounds of the formula I for the production of a medicament for the treatment of disorders caused by implants, defects, inflammations and of osteolytic disorders such as osteoporosis, thrombosis, cardiac infarct and arteriosclerosis, and also for the acceleration and reinforcement of the integration process of the implant or of the biocompatible surface into the tissue.
Appropriate thiol anchor-carrying peptides can be bonded covalently to gold-plated carriers, such as, for example, implants, affinity chromatography media, or microtitre plates.
The invention also relates to the use of the novel compounds of the formula I in affinity chromatography for eluting bound proteins.
In particular, they can be used as integrin ligands for eluting integrins.
The abbreviations of amino acid residues mentioned above and below stand for the residues of the following amino acids:
In addition, the following abbreviations have the meanings given below:
If the abovementioned amino acids can occur in several enantiomeric forms, then all these forms and also their mixtures (e.g. the DL forms) are included above and below, e.g. as a constituent of the compounds of the formula I. In addition, the amino acids can be provided, e.g. as a constituent of compounds of the formula I, with appropriate protective groups known per se. In particular, side chain modifications of the arginine, as have been carried out, for example, in the case of the non-peptide αvβ3-antagonists (e.g. by R. Keenan et al., Abstr. Pap. 211th ACS National Meeting (New Orleans, USA) 1996, MEDI 236), can also be employed in the case of the cyclopeptides, such as, for example, benzimidazole derivatives instead of the guanidine group.
So-called prodrug derivatives are also included in the compounds according to the invention, i.e. compounds of the formula I which are modified with, for example, alkyl or acyl groups, sugars or oligopeptides, and which are rapidly cleaved in the body to give the active compounds according to the invention.
These also include biodegradable polymer derivatives of the compounds according to the invention, such as is described, for example, in J. Pharm. 115, 61-67 (1995).
The invention furthermore relates to a process for the preparation of compounds of the formula I according to Claim 1 and their salts, characterized in that
Above and below, the radicals R, Q, X and L have the meanings indicated in the formulae I, II, III, IV, V, VI, VII, VIII and IX, if not expressly indicated otherwise.
In the above formulae, alkyl is preferably methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl or tert-butyl, additionally also pentyl, 1-, 2- or 3-methylbutyl, 1,1-, 1,2- or 2,2-dimethylpropyl, 1-ethylpropyl, hexyl, 1-, 2-, 3- or 4-methylpentyl, 1,1-, 1,2-, 1,3-, 2,2-, 2,3- or 3,3-dimethylbutyl, 1 or 2-ethylbutyl, 1-ethyl-1-methylpropyl, 1-ethyl-2-methylpropyl, 1,1,2- or 1,2,2-trimethylpropyl.
R1 is R2, R9, R2—R9—R2, phenylene which is unsubstituted or mono- or disubstituted by R5, where the chain length of R5 is in each case independent of one another, or R1 is absent; in particular R1 is alkylene having 1-10 C atoms.
Alkylene is preferably methylene, ethylene, butylene, pentylene or hexylene, additionally heptylene, octylene, nonylene or decylene.
Alylenephenyl is preferably benzyl or phenethyl. Alkylenephenylalkylene is preferably 4-methylenebenzyl or 4-ethylenebenzyl.
Q is preferably, for example, the 6-aminohexanoic acid (6-aminocaproic acid) radical, the succinyl radical, the —(CO—CH2—O—CH2CH2—O—CH2CH2—NH)—, the —(CO—CH2—O—CH2CH2—O—CH2CH2—NH—)—CO—(CH2)5—NH—, the —(CO—(CH2)5—NH)2— radical or the —(CO—CH2—O—CH2CH2—O—CH2CH2—NH—)2CO—(CH2)5—NH— radical.
M is preferably Dap, Ser, Cys, Asp, D-Asp, Dab, homoserine, homocysteine, Glu, D-Glu, Thr, Orn, Lys, D-Lys, 4-aminomethyl-Phe or 4-aminomethyl-D-Phe.
The amino acids and amino acid residues mentioned in the meanings for Z can also be derivatized, the N-methyl, N-ethyl, N-propyl, N-benzyl and Cα-methyl derivatives being preferred. Derivatives of Asp and Glu, in particular the methyl, ethyl, propyl, butyl, tert-butyl, neopentyl or benzyl esters of the side chain carboxyl groups are furthermore preferred, additionally also derivatives of Arg which can be substituted on the —NH—C(═NH)—NH2— group by an acetyl, benzoyl, methoxycarbonyl or ethoxycarbonyl radical.
Z is preferably M, furthermore preferably homo-Phe-M, phenylglycine, D-Phe-M, D-Trp-M, D-Tyr-M, D-Phe-Lys, D-Phe-D-Lys, D-Trp-Lys, D-Trp-D-Lys, D-Tyr-Lys, D-Tyr-D-Lys, D-Phe-Orn, D-Phe-Dab, D-Phe-Dap, D-Phe-D-Orn, D-Phe-D-Dab, D-Phe-D-Dap, D-Phe-4-aminomethyl-Phe, D-Phe-4-aminomethyl-D-Phe, D-Trp-4-aminomethyl-Phe, D-Trp-4-aminomethyl-D-Phe, D-Tyr-4-aminomethyl-Phe, D-Tyr-4-aminomethyl-D-Phe, D-Phe-Asp, D-Phe-D-Asp, D-Trp-Asp, D-Trp-D-Asp, D-Tyr-Asp, D-Tyr-D-Asp, D-Phe-Cys, D-Phe-D-Cys, D-Trp-Cys, D-Trp-D-Cys, D-Tyr-Cys, D-Tyr-D-Cys, Phe-D-Lys, Trp-D-Lys, Tyr-D-Lys, Phe-Orn, Phe-Dab, Phe-Dap, Trp-Orn, Trp-Dab, Trp-Dap, Tyr-Orn, Tyr-Dab, Tyr-Dap, Phe-4-aminomethyl-D-Phe, Trp-4-aminomethyl-D-Phe, Tyr-4-aminomethyl-D-Phe, Phe-D-Asp, Trp-D-Asp, Tyr-D-Asp, Phe-D-Cys, Trp-D-Cys, Tyr-D-Cys, Phg-M, D-Phe-Lys-Gly, D-Phe-M-Gly, D-Trp-Lys-Gly, D-Trp-M-Gly, D-Tyr-Lys-Gly, D-Tyr-M-Gly, D-Phe-Val-Lys, D-Phe-Gly-Lys, D-Phe-Ala-Lys, D-Phe-Ile-Lys, D-Phe-Leu-Lys, D-Trp-Val-Lys, D-Trp-Gly-Lys, D-Trp-Ala-Lys, D-Trp-Ile-Lys, D-Trp-Leu-Lys, D-Tyr-Val-Lys, D-Tyr-Gly-Lys, D-Tyr-Ala-Lys, D-Tyr-Ile-Lys, D-Tyr-Leu-Lys.
The radical —R6—R4 is preferably 2-, 3- or 4-hydroxybenzyl, 2-, 3- or 4-aminobenzyl, 2-, 3- or 4-mercaptobenzyl, 2-, 3- or 4-carboxybenzyl, additionally preferably 2-, 3- or 4-hydroxyphenethyl, 2-, 3- or 4-aminophenethyl, 2-, 3- or 4-mercaptophenethyl, 2-, 3- or 4-carboxyphenethyl.
Cycloalkylene is preferably cyclopropylene, 1,2- or 1,3-cyclobutylene, 1,2- or 1,3-cyclopentylene, 1,2-, 1,3- or 1,4-cyclohexylene, additionally 1,2-, 1,3- or 1,4-cycloheptylene.
R10 is H or an S protective group, such as, for example, trityl.
An amino protective group is preferably acetyl, propionyl, butyryl, phenylacetyl, benzoyl, toluyl, POA, methoxycarbonyl, ethoxycarboryl, 2,2,2-trichloro-ethoxycarbonyl, BOC, 2-iodoethoxycarbonyl, CBZ (“carbobenzoxy”), 4-methoxybenzyloxycarbonyl, FMOC, Mtr, benzyl, Pbf or Pmc.
Hal is preferably F, Cl or Br, but also I.
The compounds of the formula I can have one or more chiral centres and therefore occur in various stereo-isomeric forms. The formula I includes all these forms.
Accordingly, the invention relates in particular to those compounds of the formula I in which at least one of the radicals mentioned has one of the preferred meanings indicated above. Some preferred groups of compounds can be expressed by the following subformulae Ia to If, which correspond to the formula I and in which the radicals not designated in greater detail have the meaning indicated in the formula I, but in which
The compounds of the formula I and also the starting substances for their preparation are otherwise prepared by methods known per se, such as are described in the literature (e.g. in the standard works such as Houben-Weyl, Methoden der Organischen Chemie [Methods of Organic Chemistry], Georg-Thieme-Verlag, Stuttgart), namely under reaction conditions which are known and suitable for the reactions mentioned. In this case use can also be made of variants which are known per se, but not mentioned here in greater detail.
If desired, the starting substances can also be formed in situ in such a way that they are not isolated from the reaction mixture, but immediately reacted further to give the compounds of the formula I.
Compounds of the formula I can preferably be obtained by reacting compounds of the formula II with compounds of the formula III.
As a rule, the compounds of the formulae II and III are known. If they are not known, they can be prepared by methods known per se.
In the compounds of the formula III, the radical L is preferably a preactivated carboxylic acid, preferably a carboxylic acid halide, symmetrical or mixed anhydride or an active ester. Radicals of this type for the activation of the carboxyl group in typical acylation reactions are described in the literature (e.g. in the standard works such as Houben-Weyl, Methoden der Organischen Chemie [Methods of Organic Chemistry], Georg-Thieme-Verlag, Stuttgart).
Activated esters are expediently formed in situ, e.g. by addition of HOBt or N-hydroxysuccinimide. L is preferably H, F, Cl, Br or —ON-succinimide.
As a rule, the reaction is carried out in an inert solvent, in the presence of an acid-binding agent, preferably of an organic base such as DIPEA, triethylamine, dimethylaniline, pyridine or ouinoline or of an excess of the carboxyl component of the formula III.
The addition of an alkali metal or alkaline earth metal hydroxide, carbonate or bicarbonate or of another salt of a weak acid of the alkali metals or alkaline earth metals, preferably of potassium, sodium, calcium or caesium, may be favourable.
Depending on the conditions used, the reaction time is between a few minutes and 14 days, the reaction temperature between approximately −30° and 140°, normally between −10° and 90°, in particular between approximately 0° and approximately 70°.
Suitable inert solvents are, for example, hydrocarbons such as hexane, petroleum ether, benzene, toluene or xylene; chlorinated hydrocarbons such as trichloroethylene, 1,2-dichloroethane, carbon tetrachloride, chloroform or dichloromethane; alcohols such as methanol, ethanol, isopropanol, n-propanol, n-butanol or tert-butanol; ethers such as diethyl ether, diisopropyl ether, tetrahydrofuran (THF) or dioxane; glycol ethers such as ethylene glycol monomethyl or monoethyl ether (methyl glycol or ethyl glycol), ethylene glycol dimethyl ether (diglyme); ketones such as acetone or butanone; amides such as acetamide, N-methylpyrrolidone, dimethylacetamide or dimethyl-formamide (DMF); nitrites such as acetonitrile; sulfoxides such as dimethyl sulfoxide (DMSO); carbon disulfide; carboxylic acids such as formic acid or acetic acid; nitro compounds such as nitromethane or nitrobenzene; esters such as ethyl acetate, water or mixtures of the solvents mentioned.
Compounds of the formula I can furthermore be obtained by reacting compounds of the formula IV with compounds of the formula V.
As a rule, the starting compounds of the formulae IV and V are known. If they are not known, they can be prepared by methods known per se.
In the compounds of the formula V, the radical L is preferably a preactivated carboxylic acid, preferably a carboxylic acid halide, symmetrical or mixed anhydride or an active ester. Radicals of this type for the activation of the carboxyl group in typical acylation reactions are described in the literature (e.g. in the standard works such as Houben-Weyl, Methoden der Organischen Chemie [Methods of Organic Chemistry], Georg-Thieme-Verlag, Stuttgart).
L is preferably F, Cl, Br or —ON-succinimide.
The reaction of the compounds of the formula IV with compounds of the formula V is carried out under the same conditions, concerning the reaction time, temperature and solvent, as is described for the reaction of the compounds of the formula II with compounds of the formula III.
Compounds of the formula I can furthermore be obtained by reacting compounds of the formula VI with compounds of the formula VII.
As a rule, the starting compounds of the formulae VI and VII are known. If they are not known, they can be prepared by methods known per se.
In the compounds of the formula VI the radical L is preferably a preactivated carboxylic acid, preferably a carboxylic acid halide, symmetrical or mixed anhydride or an active ester. Radicals of this type for the activation of the carboxyl group in typical acylation reactions are described in the literature (e.g. in the standard works such as Houben-Weyl, Methoden der Organischen Chemie [Methods of Organic Chemistry], Georg-Thieme-Verlag, Stuttgart).
L is preferably F, Cl, Br or —ON-succinimide.
The reaction of the compounds of the formula VI with compounds of the formula VII is carried out under the same conditions, concerning the reaction time, temperature and solvent, as is described for the reaction of the compounds of the formula II with compounds of the formula III.
Compounds of the formula I can furthermore be obtained by reacting compounds of the formula VIII with compounds of the formula IX.
As a rule, the starting compounds of the formulae VIII and IX are known. If they are not known, they can be prepared by methods known per se.
In the compounds of the formula VIII, the radical L is preferably a preactivated carboxylic acid, preferably a carboxylic acid halide, symmetrical or mixed anhydride or an active ester. Radicals of this type for the activation of the carboxyl group in typical acylation reactions are described in the literature (e.g. in the standard works such as Houben-Weyl, Methoden der Organischen Chemie [Methods of Organic Chemistry], Georg-Thieme-Verlag, Stuttgart).
L is preferably F, Cl, Br or —ON-succinimide.
The reaction of the compounds of the formula VIII with compounds of the formula IX is carried out under the same conditions, concerning the reaction time, temperature and solvent, as is described for the reaction of the compounds of the formula II with compounds of the formula III.
Cyclic compounds of the formula II can be prepared by cyclization of the linear compounds, such as described, for example, in DE 43 10 643, in Houben-Weyl, l.c., Volume 15/II, pages 1 to 806 (1974) or by S. Zimmer, E. Hoffmann, G. Jung and H. Kessler, Liebig's Ann. Chem. 1993, 497-501.
The linear peptides can be synthesized, for example, according to R. B. Merrifield, Angew. Chemie 1985, 97, 801-812.
Open-chain linear compounds, such as, for example, compounds of the formula III can otherwise be prepared by customary methods of amino acid and peptide synthesis, e.g. also by the solid-phase synthesis according to Merrifield (see also, for example, B. F. Gysin and R. B. Merrifield, J. Pin. Chem. Soc. 94, 3012 ff. (1972)).
The compounds of the formula I can furthermore be obtained by liberating them from their functional derivatives by solvolysis, in particular hydrolysis, or by hydrogenolysis.
Preferred starting substances for the solvolysis or hydrogenolysis are those which, instead of one or more free amino and/or hydroxyl groups, contain corresponding protected amino and/or hydroxyl groups, preferably those, which instead of an H atom which is bonded to an N atom, carry an amino protective group, e.g. those which correspond to the formula I, but instead of an NH2 group contain an NHR′ group (in which R′ is an amino protective group, e.g. BOC or CBZ).
Starting substances are furthermore preferred which, instead of the H atom of a hydroxyl group, carry a hydroxyl protective group, e.g. those which correspond to the formula I, but instead of a hydroxyphenyl group contain an R″O-phenyl group (in which R″ is a hydroxy Protective group).
A number of—identical or different—protected amino and/or hydroxyl groups can also be present in the molecule of the starting substance. If the protective groups present are different from one another, in many cases they can be removed selectively.
The expression “amino protective group” is generally known and relates to groups which are suitable for protecting (for blocking) an amino group from chemical reactions, but which are easily removable after the desired chemical reaction has been carried out at other positions in the molecule. Typical groups of this type are, in particular, unsubstituted or substituted acyl, aryl, aralkoxymethyl or aralkyl groups. Since the protective groups are removed after the desired reaction (or reaction sequence), their nature and size is otherwise uncritical; preferably, however, those having 1-20, in particular 1-8, C atoms are preferred. The expression “acyl group” is to be interpreted in the widest sense in connection with the present process. It includes acyl groups derived from aliphatic, araliphatic, aromatic or heterocyclic carboxylic acids or sulfonic acids and also, in particular, alkoxycarbonyl, aryloxycarbonyl and especially aralkoxycarbonyl groups. Examples of acyl groups of this type are alkanoyl such as acetyl, propionyl, butyryl; aralkanoyl such as phenylacetyl; aroyl such as benzoyl or toluyl; aryloxy-alkanoyl such as POA; alkoxycarbonyl such as methoxycarbonyl, ethoxycarbonyl, 2,2,2-trichloro-ethoxycarbonyl, BOC, 2-iodoethoxycarbonyl; aralkyloxy-carbonyl such as CBZ (“carbobenzoxy”), 4-methoxy-benzyloxycarbonyl, FMOC; arylsullonyl such as Mtr, Pbf or Pmc. Preferred amino protective groups are BOC and Mtr, additionally CBZ, Fmoc, benzyl and acetyl.
The expression “hydroxyl protective group” is likewise generally known and relates to groups which are suitable or protecting a hydroxyl group from chemical reactions, but which are easily removable after the desired chemical reaction has been carried out at other positions in the molecule. Typical groups of this type are the abovementioned unsubstituted or substituted aryl, aralkyl or acyl groups and additionally also alkyl groups. The nature and size of the hydroxyl protective groups is not critical, since they are removed again after the desired chemical reaction or reaction sequence; groups containing 1-20, in particular 1-10, C atoms are preferred. Examples of hydroxyl protective groups are, inter alia, benzyl, p-nitrobenzyl, p-toluenesulfonyl, tert-butyl and acetyl, benzyl and tert-butyl being particularly preferred. The COOH groups in aspartic acid and glutamic acid are preferably protected in the form of their tert-butyl esters (e.g. Asp(OBut)).
The liberation of the compounds of the formula I from their functional derivatives is carried out—depending on the protective group used—, for example using strong acids, expediently using TFA or perchloric acid, but also using other strong inorganic acids such as hydrochloric acid or sulfuric acid, strong organic carboxylic acids such as trichloroacetic acid or sulfonic acids such as benzene- or p-toluenesulfonic acid. The presence of an additional inert solvent is possible, but not always necessary. Suitable inert solvents are preferably organic solvents, for example carboxylic acids such as acetic acid, ethers such as tetrahydrofuran or dioxane, amides such as DMF, halogenated hydrocarbons such as dichloromethane, additionally also alcohols such as methanol, ethanol or isopropanol, and also water. Mixtures of the above-mentioned solvents are additionally suitable. TFA is preferably used in an excess without addition of a further solvent, perchloric acid in the form of a mixture of acetic acid and 70% perchloric acid in the ratio 9:1. The reaction temperatures for the cleavage are expediently between approximately 0 and approximately 50°, the reaction is preferably carried out between 15 and 30° (room temperature).
The groups BOC, OBut, Pbf, Pmc and Mtr can be removed, or example, preferably using TFA in dichloromethane or using approximately 3 to 5 N HCl in dioxane at 15-30°, she FMOC group using an approximately 5 to 50% solution of di-methylamine, diethylamine or piperidine in DMF at 15-30°.
The trityl group is employed for the protection of the amino acids hisitidine, asparagine, glutamine and cysteine. Removal is carried out, depending on the desired final product, using TFA/10% thiophenol, the trityl group being removed from all the abovementioned amino acids, when using TFA/anisole or TFA/thioanisole the trityl group only being removed from His, Asn and Gln, compared to which that on the Cys side chain remains. The Pbf (pentamethylbenzofuranyl) group is employed for the protection of Arg. Removal is carried out, for example, using TFA in dichloromethane.
Hydrogenolytically removable protective groups (e.g. CBZ or benzyl) can be removed, for example, by treating with hydrogen in the presence of a catalyst (e.g. of a noble metal catalyst such as palladium, expediently on a support such as carbon). Suitable solvents in this case are those indicated above, in particular, for example, alcohols such as methanol or ethanol or amides such as DMF. As a rule, the hydrogenolysis is carried out at temperatures between approximately 0 and 100° and pressures between approximately 1 and 200 bar, preferably at 20-30° and 1-10 bar. Hydrogenolysis of the CBZ group is readily carried out, for example, on 5 to 10% Pd/C in methanol or using ammonium formate (instead of hydrogen) on Pd/C in methanol/DMF at 20-30°.
A base of the formula I can be converted into the associated acid addition salt using an acid, for example by reaction of equivalent amounts of the base and of the acid in an inert solvent such as ethanol and subsequent evaporation. Possible acids for this reaction are in particular those which give physiologically acceptable salts. Thus inorganic acids can be used, e.g. sulfuric acid, nitric acid, hydrohalic acids such as hydrochloric acid or hydrobromic acid, phosphoric acids such as orthophosphoric acid, sulfamic acid, additionally organic acids, in particular aliphatic, alicyclic, araliphatic, aromatic or heterocyclic mono-or polybasic carboxylic, sulfonic or sulfuric -acids, e.g. formic acid, acetic acid, propionic acid, pivalic acid, diethylacetic acid, malonic acid, succinic acid, pimelic acid, fumaric acid, maleic acid, lactic acid, tartaric acid, malic acid, citric acid, gluconic acid, ascorbic acid, nicotinic acid, isonicotinic acid, methane-or ethanesulfonic acid, ethanedisulfonic, acid, 2-hydroxy-acid, benzenesulfonic ethanesulfonic acid, p-toluenesulfonic acid, naphthalenemono- and -disulfonic acids, and laurylsulfuric acid. Salts with physiologically unacceptable acids, e.g. picrates, can be used for the isolation and/or purification of the compounds of the formula I.
On the other hand, an acid of the formula I can be converted into one of its physiologically acceptable metal or ammonium salts by reaction with a base. Suitable salts in this case are in particular the sodium, potassium, magnesium, calcium and ammonium salts, additionally substituted ammonium salts, e.g. the dimethyl-, diethyl- or diisopropylammonium salts, monoethanol-, diethanol- or diisopropylammonium salts, cyclohexyl- or dicyclohexylammonium salts, dibenzylethylenediammonium salts, furthermore, for example, salts with arginine or lysine.
Above and below, all temperatures are indicated in ° C. In the following examples “customary working up” means: if necessary, water is added, the mixture is adjusted, if necessary, depending on the constitution of the final product to a pH of between 2 and 10 and extracted with ethyl acetate or dichloromethane, the organic phase is separated off, dried over sodium sulfate and evaporated, and the residue is purified by chromatography on silica gel and/or by crystallization. Rf values on silica gel: eluent: ethyl acetate/methanol 9:1.
RT=Retention time (minutes) on HPLC in the following systems:
[A]
DMPP resin stands for 4-(2′,4′-dimethoxyphenyl-hydroxymethyl)phenoxy resin, which allows, for example, the synthesis of side chain-protected peptides; TCP resin denotes trityl chloride polystyrene resin.
a) 0.2 mmol of succinic anhydride is added to a solution of 0.1 mmol of cyclo-(Arg(Pbf)-Gly-Asp(OBut)-D-Phe-Lys) (“A”) [obtainable by cyclization of H-Asp(OBut)-D-Phe-Lys(Z)-Arg(Pbf)-Gly-OH to cyclo-(Arg(Pbf)-Gly-Asp(OBut)-D-Phe-Lys(Z)) and selective removal of the Z group by hydrogenolysis] in 5 ml of DMF.
The mixture is stirred at room temperature for 5 hours and cyclo-(Arg(Pbf)-Gly-Asp(OBut)-D-Phe-Lys(Nε-Su)) (“B”) is obtained after customary working up.
b) 1 equivalent of cysteamine hydrochloride and 1 equivalent of triphenylmethanol are dissolved in glacial acetic acid at 60° and treated with stirring with 1.1 equivalents of BF3 etherate. The mixture is stirred for one hour and worked up in the customary manner and Trt-cysteamine hydrochloride (“C”) is obtained.
By reaction of “B” with “C” in dichloromethane with the addition of EDCI hydrochloride, cyclo-(Arg(Pbf)-Gly-Asp(OBut)-D-Phe-Lys(Nε—CO—CH2CH2CO—NH—CH2CH2—S-Trt)) is obtained after customary working up.
After removal of the protective groups cyclo-(Arg-Gly-Asp-D-Phe-Lys(Nε—CO—CH2CH2CO—NH—CH2CH2—SH)) is obtained; RT [B] 18.3; FAB 763.
Analogously, by reaction of “C” with cyclo-(Arg(Pbf)-Gly-Asp(OBut)-D-Phe-Lys(Nε-Su)-Gly) and removal of the protective groups the compound cyclo-(Arg-Gly-Asp-D-Phe-Lys(Nε—CO—CH2CH2CO—NH—CH2CH2—SH)-Gly) is obtained.
a) 1.2 equivalents of acryolyl chloride are added at 0° to a suspension of 10 mmol of 6-aminohexanoic acid and 1.8 equivalents of calcium hydroxide in water. The mixture is filtered and 6-acrylamidohexanoic acid (“D”) is obtained after customary working up.
b) A solution of 10 mmol of “D” and 1 equivalent of N-hydroxysuccinimide in 50 ml of dichloromethane is treated at 0° with 1.2 equivalents of EDCI hydrochloride and stirred for 1 hour. 10 μl of glacial acetic acid are added, the mixture is worked up in the customary manner and HOBT 6-acrylamidohexanoate (“E”) is obtained.
c) By reaction of “A” with “E” in DMF, cyclo-(Arg(Pbf)-Gly-Asp(OBut)-D-Phe-Lys(Nε—CO—(CH2)5—NH—CO—CH═CH2)) is obtained after customary working up.
After removal of the protective groups cyclo-(Arg-Gly-Asp-D-Phe-Lys(Nε—CO—(CH2)5—NH—CO—CH═CH2)) is obtained; RT [A] 22.8; ESI 771.
The compound cyclo-(Arg-Gly-Asp-D-Phe-Lys Nε—CO—(CH2)5—NH—CO—CH═CH2)-Gly) is obtained analogously.
a) 2 mmol of “E”, dissolved in ethanol/chloroform, are added at 0° to a solution of 10 mmol of 6-amino-hexanoic acid in aqueous sodium phosphate buffer (pH 8). The mixture is filtered and 6-(6-acrylamido-hexanoylamido)hexanoic acid (“F”)
is obtained after customary working up.
b) By reaction of “A” with “F” in DMF with addition of EDCI hydrochloride, cyclo-(Arg(Pbf)-Gly-Asp(OBut)-D-Phe-Lys(Nε—CO—(CH2)5—NH—CO—(CH2)5—NH—CO—CH═CH2)) is obtained after customary working up.
After removal of the protective groups cyclo-(Arg-Gly-Asp-D-Phe-Lys(Nε—CO—(CH2)5—NH—CO—(CH2)5—NH—CO—CH═CH2)) is obtained; RT [C] 23.5; ESI 884.
The compound cyclo-(Arg-Gly-Asp-D-Phe-Lys(Nε—CO—(CH2)5—NH—CO—(CH2)5—NH—CO—CH═CH2)-Gly) is obtained analogously.
a) By coupling of 6-acrylamidohexanoic acid to [2-(2-aminoethoxy)ethoxy]acetic acid-TCP resin with addition of HOBt and TBTU in NMP {2-[2-(6-acrylamido-hexanoylamido)ethoxy]ethoxy}acetic acid-DMPP resin is obtained.
The resin is washed with dichloromethane/acetic acid/trifluoroethanol (6:3:1) and {2-[2-(6-acrylamido-hexanoylamido)ethoxy]ethoxy}acetic acid (“G”) is obtained.
b) By reaction of “G” with “A” in DMF with addition of EDCl×HCl, the compound cyclo-(Arg(Pbf)-Gly-Asp(OBut)-D-Phe-Lys(Nε—CO—CH2—O—CH2CH2—O—CH2CH2—NH—CO—(CH2)5—NH—CO—CH═CH2)) is obtained.
After removal of the protective groups cyclo-(Arg-Gly-Asp-D-Phe-Lys(Nε—CO—CH2—O—CH2CH2—O—CH2CH2—NH—CO—(CH2)5—NH—CO—CH═CH2)) is obtained; RT [C] 22.5; ESI 916.
The compound cyclo-(Arg-Gly-Asp-D-Phe-Lys(Nε—CO—CH2—O—CH2CH2—O—CH2CH2—NH—CO—(CH2)5—NH—CO—CH═CH2)-Gly) is obtained analogously.
Analogously, by reaction of {2-[2-(2-{2-[2-(6-acrylamidohexanoylamido)ethoxy]-ethoxy]acetylamido)ethoxy]ethoxy}acetic acid
with “A” the compound cyclo-(Arg (Pbf)-Gly-Asp(OBut)-D-Phe-Lys(Nε—(CO—CH2—O—CH2CH2—O—CH2CH2—NH)2—CO—(CH2)5—NH—CO—CH═CH2)) is obtained.
After removal of the protective groups cyclo-(Arg-Gly-Asp-D-Phe-Lys(Nε—(CO—CH2—O—CH2CH2—O—CH2CH2—NH)2—CO—(CH2)5—NH—CO—CH═CH2)) is obtained; RT [C] 22.75; ESI 1061.
Cyclo-(Arg-Gly-Asp-D-Phe-Lys(Nε—(CO—CH2—O—CH2CH2—O—CH2CH2—NH)2—CO—(CH2)5—NH—CO—CH═CH2)-Gly) is obtained analogously.
Analogously to Example 1, by reaction of the (“G”)-cyclopeptides below
The adhesion of mouse MC3T3 H1 osteoblast cultures in vitro to RGD peptide-coated material surfaces was investigated. In the course of this, 50,000 cells/cm2 were inoculated and, after incubation in serum-free medium at 37°/95% atmospheric humidity for one hour, the proportion of adherent cells was determined.
Cell adhesion rate [%]=adhered cells/inoculated cells×100
Peptide: cell adhesion rate [%]
Number | Date | Country | Kind |
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197 55 800 | Dec 1997 | DE | national |
This application is a divisional of application Ser. No. 09/581,575, filed Jun. 15, 2000, now U.S. Pat. No. 6,610,826, which is a §371 of PCT/EP98/08003, filed Dec. 9, 1998, which claims priority to German application 19755800.3, filed Dec. 16, 1997.
Number | Name | Date | Kind |
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5939383 | Remacle et al. | Aug 1999 | A |
6566491 | Jonczyk et al. | May 2003 | B2 |
Number | Date | Country |
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0 844 252 | May 1998 | EP |
Number | Date | Country | |
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20020198142 A1 | Dec 2002 | US |
Number | Date | Country | |
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Parent | 09581575 | US | |
Child | 10183410 | US |