PYRIDINE DERIVATIVES

Abstract: Compounds of the formula (I), wherein X and R1 to R5 are as defined in the description, are useful for treating disorders mediated full or in part by mGluR5.

Description: Pyridine derivatives The invention relates to the use of 2-arylalkenyl-, 2-heteroarylalkenyl-, 2-arylalkynyl-, 2- heteroarylalkyπyl-, 2-arylazo- and 2-heteroaryiazo-pyridines for modulating the activity of mGluRs and for treating mGluRδ mediated diseases, to pharmaceutical compositions for use in such therapy, as well as to novel 2-arylaikenyl-, 2-heteroaryialkenyl-, 2-arylalkynyl-, 2-heteroarylalkynyl-, 2-arylazo- and 2-heteroarylazo-pyridines. It has been found that 2-aryialkenyl-, 2-heteroarylalkenyl-, 2-arylalkynyl-, 2- heteroarylalkynyl-, 2-arylazo- and 2-heteroarylazo-pyridines including the pharmaceutically acceptable salts (hereinafter agents of the invention) are useful as modulators of mGluRs. Modulation of mGluRs can be demonstrated in a variety of ways, inter alia, in binding assays and functional assays such as second messenger assays or measurement of changes in intracelluiar calcium concentrations. For example, measurement of the inositol phosphate turnover in recombinant cell lines expressing hmGIuRδa showed, for selected agents of the invention, IC 50 values of about 1 nM to about 50μM. In particular, the agents of the invention have valuable pharmacological properties. For example, they exhibit a marked and selective modulating, especially antagonistic, action at human metabotropic glutamate receptors (mGluRs). This can be determined in vitro for example at recombinant human metabotropic glutamate receptors, especially PLC-coupled subtypes thereof such as mGluRδ, using different procedures like, for example, measurement of the inhibition of the agonist induced elevation of intracelluiar Ca 2+ concentration in accordance with L. P. Daggett et al. Neuropharm. Vol. 34, pages 871 -886 (1995), P. J. Flor et al., J. Neurochem. Vol. 67, pages 58-63 (1996) or by determination to what extent the agonist induced elevation of the inositol phosphate turnover is inhibited as described by T. Knoepfel et al. Eur. J. Pharmacol. Vol. 288, pages 389-392 (1994), L. P. Daggett et al., Neuropharm. Vol. 67, pages 58-63 (1996) references cited therein, isolation and expression of human mGluR subtypes are described in US-Patent No. 5,521 ,297. Selected agents of the invention showed IC 50 values for the inhibition of the quisqualate- induced inositol phosphate turnover, measured in recombinant cells expressing hmGluR5a of about 1 nM to about 50μM. Accordingly the invention relates to agents of the invention for use in the treatment of disorders associated with irregularities of the glutamatergic signal transmission, and of nervous system disorders mediated full or in part by mGluR5. Disorders associated with irregularities of the glutamatergic signal transmission are for example epilepsy, cerebral ischemias, especially acute ischemias, ischemic diseases of the eye, muscle spasms such as local or general spasticity and, in particular, convulsions or pain. Nervous system disorders mediated full or in part by mGluRδ are for example acute, traumatic and chronic degenerative processes of the nervous system, such as Parkinson's disease, senile dementia, Alzheimer's disease, Huntington's chorea, amyotrophic lateral sclerosis and multiple sclerosis, psychiatric diseases such as schizophrenia and anxiety, depression and pain. The invention also relates to the use of agents of the invention, in the treatment of disorders associated with irregularities of the glutamatergic signal transmission, and of nervous system disorders mediated full or in part by Group I mGluRs. Furthermore the invention relates to the use of agents of the invention for the manufacture of a pharmaceutical composition designed for the treatment of disorders associated with irregularities of the glutamatergic signal transmission, and of nervous system disorders mediated full or in part by Group I mGluRs. In a further aspect the invention relates to a method of treating disorders mediated full or in part by group I mGluRs (preferentially mGluP.5) which method comprises administering to a warm-blooded organism in need of such treatment a therapeutically effective amount of an agent of the invention. In still a further aspect, the invention relates to novel 2-arylalkenyl-, 2-heteroarylalkenyl-, 2- arylalkynyl-, 2-heteroarylalkyπyl-, 2-arylazo- and 2-heteroarylazo-pyridines and their salts, and to a process for preparing them. Moreover the invention relates to a pharmaceutical composition comprising as pharmaceutical active ingredient, together with customary pharmaceutical excipients, a novel 2-arylalkenyl-, 2-heteroarylalkenyl-, 2-arylalkynyl-, 2-heteroaryla!kynyl-, 2-arylazo- or 2-heteroarylazo-pyridine or a pharmaceutically acceptable salt thereof. Agents of the invention are for example compounds of formula wherein Ri denotes hydrogen, lower alkyl, hydroxy-lower alkyl lower alkyl-amino, piperidino, carboxy, esterified carboxy, amidated carboxy, unsubstituted or lower alkyl-, lower alkoxy-, halo- and/or trifluoromethyl-substituted N-lower-alkyl-N-phenylcarbamoyl, lower alkoxy, halo-lower alkyl or halo-lower alkoxy, R 2 denotes hydrogen, lower alkyl, carboxy, esterified carboxy, amidated carboxy, hydroxy- lower alkyl, hydroxy, lower alkoxy or lower alkanoyloxy, 4-(4-fluoro-benzoyl)-piperidin-1-yl- carboxy, 4-t.-butyloxycarbonyl-piperazin-1 -yl-carboxy, 4-(4-azido-2-hydroxybenzoyl)- piperazin-1 -yl-carboxy or 4-(4-azido-2-hydroxy-3-iodo-benzoyl)-piperazin-1 -yl-carboxy, R 3 represents hydrogen, lower alkyl, carboxy, lower alkoxy-carbonyl, lower alkyl-carbamoyl, hydroxy- lower alkyl, di- lower alkyl- aminomethyl, morpholinocarbonyl or 4-(4-fluoro- benzoyl)-piperidin-1 -yl-carboxy, R represents hydrogen, lower alkyl, hydroxy, hydroxy-lower alkyl, amino-lower alkyl, lower alkylamino-lower alkyl, di-lower alkylamino-lower alkyl, unsubstituted or hydroxy-substituted lower alkyleneamino-lower alkyl, lower alkoxy, lower alkanoyloxy, amino-lower alkoxy, lower alkylamino-lower alkoxy, di-lower alkylamino-lower alkoxy, phthalimido-lower alkoxy, unsubstituted or hydroxy- or 2-oxo-imidazoiidin-1 -yl-substituted lower alkyleneamino-lower alkoxy, carboxy, esterified or amidated carboxy, carboxy-lower-alkoxy or esterified carboxy- lower-alkoxy, X represents an optionally halo-substituted lower alkenylene or aikynylene group bonded via vicinal unsaturated carbon atoms or an azo (-N=N-) group, and R 3 denotes an aromatic or heteroaromatic group which is unsubstituted or substituted by one or more substituents selected from lower alkyl, halo, halo-lower alkyl, halo-lower alkoxy, lower alkenyl, lower alkynyl, unsubstituted or lower alkyl-, lower alkoxy-, halo- and/or trifluoromethyl-substituted phenyl, unsubstituted or lower alkyl-, lower alkoxy-, halo- and/or trifluoromethyl-substituted phenyl-lower alkynyl, hydroxy, hydroxy-lower alkyl, lower alkanoyloxy-lower alkyl, lower alkoxy, lower alkenyloxy, lower alkylenedioxy, lower alkanoyloxy, amino-, lower alkylamino-, lower alkanoylamino- or N-lower alkyl-N-lower alkanoylamino-lower alkoxy, unsubstituted or lower alkyl- lower alkoxy-, halo- and/or trifluoromethyl-substituted phenoxy, unsubstituted or lower alkyl- lower alkoxy-, halo- and/or trifluoromethyl-substituted phenyl-lower alkoxy, acyl, carboxy, esterified carboxy, amidated carboxy, cyano, carboxy-iower alkylamino, esterified carboxy-lower alkylamino, amidated carboxy-lower alkylamino, phosphono-lower alkylamino, esterified phosphono-lower alkylamino, nitro, amino, lower alkylamino, di-lower alkylamino, acylamino, N-acyl-N-lower alkylamino, phenylamino, phenyl-lower alkylamino, cycloalkyl-lower alkylamino or heteroaryl-lower alkylamino each of which may be unsubstituted or lower alkyl- lower alkoxy-, halo- and/or trifluoromethyl-substituted, customary photoaffinity ligands and customary radioactive markers, inclusive of their N- oxides and their pharmaceutically acceptable salts. Compounds of formula I having basic groups may form acid addition salts, and compounds of the formula I having acidic groups may form salts with bases. Compounds of formula I having basic groups and in addition having at least one acidic group, may also form internal salts. Also included are both total and partial salts, that is to say salts with 1 , 2 or 3, preferably 2, equivalents of base per mole of acid of formula I, or salts with 1 , 2 or 3 equivalents, preferably 1 equivalent, of acid per mole of base of formula I. For the purposes of isolation or purification it is also possible to use pharmaceutically unacceptable salts. Only the pharmaceutically acceptable, non-toxic salts are used therapeutically and they are therefore preferred. Halo in the present description denotes fluorine, chlorine, bromine or iodine. When X represents an alkenylene group, configuration trans is preferred. Preferred compounds of formula I are those wherein X represents an optionally halo-substituted (C 2 . )alkenylene or alkynyiene group bonded via vicinai unsaturated carbon atoms, Ri is hydrogen, (C 1- ) alkyl, (C 1-4 )alkoxy, hydroxy^ L ^alkyl, cyano, ethynyl, carboxy, (Cv^alkoxycarbonyl, d d-^alkylamino, (C 1 . 6 )alkylaminocarbonyl, trifluorcmethylphenylaminocarbonyl, R 2 is hydrogen, hydroxy, (Cι_ 4 ) alkyl, hydroxy (C 1-4 ) alkyl, (d. 4 ) alkoxy, carboxy, (C- 2 . 5 )alkanoyloxy, (Cι -4 ) alkoxycarbonyl, di(C 1 . 4 )alkylamino(C 1-4 )alkanoyl, - o di(Cι. 4 )alkylaminomethyi, 4-(4-fluoro-benzoyi)-piperidin-1 -yl-carboxy, 4-t.- butyloxycarbonyi-piperazin-1 -yl-carboxy, 4-(4-azido-2-hydroxybenzoyl)-piperazin-1 -yl- carboxy or 4-(4-azido-2-hydroxy-3-iodo-benzoyl)-piperazin-1 -yl-carboxy, is hydrogen, (Cι. 4 ) alkyl, carboxy, (d- )alkoxycarbonyl, (d- )alkylcarbamoyl, hydroxy(d- )alkyl, di(Cι -4 )alkylaminomethyl, morpholinocarbonyi or 4-(4-fluoro- benzoyl)-piperidin-1 -yl-carboxy, is hydrogen, hydroxy, (C 1-4 )aikoxy, carboxy, (C 2 . 5 )alkanoy!oxy, (d-^aikoxycarbonyl, amino(d. )alkoxy, d^d-^alkylamino^-^alkoxy, di(C 1 . 4 )alkylamino(C 1 - )alkyl, carboxy (Cι. 4 )alkylcarbonyl, (d^alkoxycarbony d^alkoxy, hydroxy(d. 4 ) alkyl, di^ L ^alkylamino^ ^alkoxy, m-hydroxy-p-azidophenylcarbonylamino d-^alkoxy, and is a group of formula wherein R a and R b independently are hydrogen, hydroxy, halogen, nitro, cyano, carboxy, (Cι. )alkyl, (d. 4 )alkoxy, hydroxy(C 1 . 4 )aikyl, (Cι. )alkoxycarbonyl, (C 2 - 7 )alkanoyl, (C 2 . 5 )alkanoyloxy, (C 2 . 5 )alkanoyloxy(C 1 . )alkyl, trifluoromethyl, trifluoromethoxy, trimethylsiiy lethy ny I , (C 2 . 5 )alkynyl, amino, azido, amino (d. 4 )alkoxy, (C 2 . 5 )alkanoylamino(d. 4 )alkoxy, (d- 4 )alkylamino(Cι. )alkoxy, di(C 1 . 4 )alkylamino (d. 4 )alkoxy, (Cι. 4 )alkylamino, di(Cι. 4 )alkylamino, monohalobenzylamino, thienylmethylamino, thienylcarbonylamino, trifluoromethylphenylaminocarboπyl, tetrazolyl, (C 2 . £ )alkanoylamino, benzylcarbonyiamino, (d-^alkylaminocarbonylamino, (d-^alkoxycarbonyl-aminocarbonyiamino or (d-^alkylsulfonyl, R c is hydrogen, fluorine, chlorine, bromine, hydroxy, (d. 4 )alkyl, (C 2 . 5 )alkanoyloxy, (d^)alkoxy or cyano, and R d is hydrogen, halogen or (d. 4 )alkyl. More preferred compounds of formula I are those wherein X is as defined above and Rj is hydrogen, (d. 4 ) alkyl, (d. 4 )alkoxy, cyano, ethynyl or di(Cι. 4 )alkylamino, R 2 is hydrogen, hydroxy, carboxy, (d- 4 ) aikoxycarbonyl, di(d- 4 )alkylaminomethyl, 4-(4-fluoro-benzoyl)-piperidin-1 -yl-carboxy, 4-t.-butyloxycarbonyl-piperazin-1 -yl- carboxy, 4-(4-azido-2-hydroxybenzoyl)-piperazin-1 -yl-carboxy or 4-(4-azido-2-hydroxy- 3-iodo-benzoyl)-piperazin-1 -yl-carboxy, R 3 is as defined above, R 4 is hydrogen, hydroxy, carboxy, (C 2 . 5 )aikanoyloxy, (C 1-4 )alkoxycarbonyl, amino (d. 4 )alkoxy, di(C 1 .4)alkylamino(Cι. 4 )alkoxy, di(d. 4 )alkylamino(Cι. 4 )alkyl or R 5 is a group of formula wherein R a and R b independently are hydrogen, halogen, nitro, cyano, (d- )alkyl, (d. 4 )alkoxy, trifluoromethyl, trifluoromethoxy or (C 2 . 5 )alkynyl, and R c and R d are as defined above. The agents of the invention include, for example, the compounds described in the examples hereinafter. The usefulness of the agents of the invention in the treatment of the above-mentioned disorders could be confirmed in a range of standard tests including those indicated below: At doses of about 10 to 100 mg/kg i.p. or p.o. with pretreatment times of 5 min. to 8 hours, the agents of the invention show anticonvuisive activity in the electroshock induced convulsion model [cf. E.A. Swinyard, J. Pharm. Assoc. Scient. Ed. 38, 201 (1949) and J. Pharmacol. Exptl. Therap. 106, 319 (1952)]. At doses of about 4 to about 40 mg/kg p.o., the agents of the invention show reversal of Freund complete adjuvant (FCA) induced hyperalgesia [cf. J. Donnerer et al., Neuroscience 49, 693-698 (1992) and C.J. Woolf, Neuroscience 62, 327-331 (1994)]. For all the above mentioned indications, the appropriate dosage will of course vary depending upon, for example, the compound employed, the host, the mode cf administration and the nature and severity of the condition being treated. However, in general, satisfactory results in animals are indicated to be obtained at a daily dosage of from about 0.5 to about 100 mg/kg animal body weight. In larger mammals, for example humans, an indicated daily dosage is in the range from about 5 to 1600 mg, preferably about 10 to about 1000 mg of the compound conveniently administered in divided doses up to 4 times a day or in sustained release form. Preferred compounds for the above mentioned indications include (3-{2-[2-trans-(3,5- dichlorophenyl)-vinyl]-6-methyl-pyridin-3-yloxy}-propyl)-dimethyiamine (A), 2-methyl-6-styryl- pyridine (B), 2-(3-fluoro-phenylethynyl)-6-methyl-pyridine (C) and 2-(4-ethoxy-3- trifluoromethyl-phenylethynyl)-6-methyl-pyridine (D). It has for example been determined that in the above-mentioned electroshock induced convulsion model, compounds A and B show anticonvulsive activity with ED 5 oS of 30 and 35 mg/kg i.p. respectively (pretreatment times: 4 hours and 15 min. respectively) and that in the above-mentioned FCA induced hyperalgesia model, compounds C and D show reversal of the hyperalgesia v/ith ED 50 s of 4.2 and 19 mg/kg p.o. respectively (post-treatment time: 3 hours). As indicated above, the agents of the invention include novel 2-arylalkenyl-, 2- heteroarylalkenyl-, 2-arylalkynyl-, 2-heteroarylalkynyl-, 2-arylazo- and 2-heteroarylazo- pyridines and their salts, hereinafter referred to as "compounds of the invention". Compounds of the invention include compounds of formula I as defined above, and their salts, wherein X and Ri to R 5 are as defined above, provided that when R 3 is hydrogen, a) in compounds of the formula I in which R-i, R 2 and R 4 are hydrogen, R 5 is different from phenyl, monohalophenyl, 2,4- and 3,4-dichlorophenyl, 3- and 4-trifluoromethylphenyl, methylphenyl, 3,4- and 2,5-dimethylphenyl, 4-isopropylphenyl, 3,5-di-tert.-butylphenyl, methoxyphenyl, 3,4-dimethoxyphenyl, 2,4,5- and 3,4,5-trimethoxyphenyl, hydroxyphenyl, 3,5-dihydroxyphenyl, 4-hydroxy-3,5-dimethyl-phenyl, 3-hydroxy-4-methoxy- and 4-hydroxy- 3-methoxy-phenyl, 4-hydroxy-(3-methyl-5-tert.-butyl-, 2- and 4-acetylaminophenyl, 3,5- diisopropyl- and 3,5-di-tert.-butyl)phenyl, 4-carboxy- and 4-ethoxycarbonylphenyl, 4- cyanophenyl, 3-methoxycarbonyiphenyl, 3-carboxy-5-methoxy-phenyl, 2-pyridinyl, 5-chloro- 2-pyridinyl and 6-methyl-2-pyridinyl when X denotes ethenylene, or R 5 is different from phenyl, 4-methylphenyl, 4-methoxyphenyl, 4-bromophenyl and 2- and 4-chlorophenyl when X denotes 1 ,2-propylene attached to R 5 in 2-position, or R 5 is different from phenyl, 2- and 4-chlorophenyl and 3-methoxyphenyl when X denotes 1 ,2-propylene attached to R 5 in 1 - position, or R 5 is different from 4-methoxyphenyl when X denotes 2,3-but-2-enylene or 1 ,2- but-1 -enylene attached to R 5 in 2-position, or R 5 is different from 4-methoxyphenyl and 4- isopropyphenyl when X denotes 2,3-pent-2-enylene attached to R 5 in 3-position, or R 5 is different from phenyl, 4-methylphenyl, methoxyphenyl and 4-hydroxyphenyl when X denotes 3,4-hex-3-enylene; b) in compounds of the formula I in which R- \ is methyl and R 2 and R 4 are hydrogen, R 5 is different from phenyl, 3-methylphenyl, 2-methoxyphenyl, 2-chlorophenyl, 4-cyanophenyl, , 2-pyridinyi and 6-methyl-2-pyridinyl when X denotes ethenylene; c) in compounds of the formula I in which R-i and R 2 are hydrogen and R 4 is carboxy, R 5 is different from phenyl, 3-methylphenyl, 4-methoxyphenyl and 4-bromophenyl when X denotes ethenylene; d) in compounds of the formula I in which R-j and R 2 are hydrogen and R 4 is methyl, R 5 is different from phenyl, 3-methoxy-, 4-methoxy- and 3,4-dimethoxyphenyl, 2-chloro- and 2,4- dichlorophenyl and 6-methyl-pyrid-2yl when X denotes ethenylene or R s is different from phenyl when X is 1 ,2-prop-1-enylene attached to R 5 in 2-position; e) in compounds of the formula I wherein Ri and R 2 are hydrogen and R 4 is 2-dimethyl- aminoethoxycarbonyi or 3-dimethylaminopropyloxycarbonyl, R 5 is different from 4-methoxy- phenyl when X denotes ethenylene; f) in compounds of the formula I in which R-i and R 2 are hydrogen and R 4 is 2-dimethoxy- ethoxy, R 5 is different from phenyl, 4-methylphenyl and 4-methoxycarbonylphenyl when X denotes ethenylene; g) R 5 is different from phenyl when R-i and R 2 are hydrogen and R 4 is hydroxy or ethoxy- carbonyl, or when R-, and R 2 are hydrogen and R 4 is hydroxy, or when R^ is methyl, R 2 is hydrogen and R is methoxy, or R^ is but-1 -enyl, R 2 is hydrogen and R 4 is hydrogen, or R^ is hydrogen and R 4 is 2-dimethoxyethoxy, and X is, in each case, ethenylene, and provided that, when R 3 is hydrogen and X is ethynylene, a') R 5 is different from phenyl, 2- and 4-nitrophenyl, 4-aminophenyl, 4-chlorophenyl, 4- methylphenyl, 4-methoxyphenyl, 4-ethoxycarbonylphenyl, 5-formyl-2-methoxy-phenyl, 5- carboxy-2-methyo-phenyl and pyridyl when R^ R 2 and R 4 are hydrogen; b') in compounds of the formula I in which R 2 and R 4 are hydrogen, R 5 is different from phenyl, 3-methylphenyl. 6-methyipyridin-2-yl and 2-methoxyphenyi when R, is methyl, R 5 is different form 6-bromopyridin-2-yl when is bromo, and R 5 is different form 6- hexyloxypyridin-2-yl when R T denotes hexyloxy; c') in compounds of the formula I wherein Ri and R are hydrogen, R 5 is different from phenyl, 4-aminophenyl and 4-propylphenyl when R 2 is methyl, R 5 is different from phenyl, 4- cyanophenyl and 4-pentylphenyl when R 2 is ethyl, R 5 is different form 3-cyano-4-ethoxy- phenyland 3-bromo-4-methoxy-phenyi when R 2 is butyl, R 5 is different from 4-methoxy- phenyl and 4 butyloxyphenyl when R 2 is pentyl, R 5 is different form 4-ter.-butylphenyl, 3- tert.-butyl-4-hydroxy-phenyl, 4-tert.-butyl-3-hydroxy-phenyl,and 4-hexyioxyphenyl when R 2 is carboxy, R 5 is different from phenyl when R 2 is methoxycarbonyi or methylcarbamoyl, R 4 is different form 3-tert.-butyiphenyl, 3-tert.-butyl-4-hydroxy-phenyl and 4-(4- methylpentyl)phenyl when R 2 is ethoxycarbonyl, and R 5 is different from 4-pentyloxyphenyl when R 2 is 2-methylbutyloxycarbonyl; d') in compounds of the formula I wherein R T and R 2 are hydrogen, R 5 is different from phenyl when R 4 is hydroxy, methyl, ethyl, carboxy, methoxycarbonyi or carbamoyl. Preferred compounds of the invention are as indicated above for the agents of the invention. The compounds of the invention can be prepared in analogy to the synthesis of known compounds of formula I. Thus the compounds of the invention which are of formula I can be prepared for example by a process which comprises a) reacting a comDOund of the formula II with a compound of the formula Y 2 — Rs (III), in which either one of Y-i and Y 2 denotes lower alkanoyl and the other one represents lower alkyl or triaryiphosphoranylidenemethyl, or one of Yi and Y 2 denotes a reactive esterified hydroxy group and the other one represents a group Y 3 — X- in which Y 3 is hydrogen or a metallic group, and R^ R 2 , R 3 , R 4 and R 5 have the meanings indicated hereinbefore and functional groups R R 2 , R 3 and R 4 as well as functional substituents of R 5 may be temporarily protected, or b) eliminating H — Y from a compound of the formula IV in which Y 4 denotes an electrofugal group and R-i, R 2 , R 3 , R 4 , X and R 5 have the meanings indicated hereinbefore and functional groups R-i, R 2 , R 3 and R 4 as well as functional substituents of R s may temporarily be protected, removing any temporary protecting groups and, if desired, converting a compound of formula I obtainable by the above-defined processes into a different compound of formula I, resolving a mixture of isomers that may be obtained into the individual isomers and/or converting a compound of formula I having at least one salt-forming group obtainable by the above-defined processes into a salt, or converting a salt obtainable by the above-defined processes into the corresponding free compound or into a different salt. A lower alkanoyl Y 2 or, more preferably, Y^ group is, for example, a C C 3 alkanoyl group, such as formyl, acetyl or propionyl, especially formyl. A lower alkyl group Y^ or, more preferably, Y 2 is, for example, a C C 3 alkyl group, such as methyl, ethyl or propyl, especially methyl. Triarylphosphoranylidenemethyl Y 2 or, more preferably, Y^ is, for example, triphenylphosphoranylidenemethyl. When one of Y-, and Y 2 denotes a reactive esterified hydroxy group and the other one represents a group of the formula Y 3 -X- in which Y 3 denotes hydrogen, the condensation is preferably performed according to the Heck coupling method, for example, in the presence of copper or of a copper catalyst or of a noble metal/phosphine catalyst, such as Palladium or a Pdll salt in the presence of triaryl phosphine, for example, Palladium acetate, and of triphenylphosphine, or in the presence of bis-triphenylphosphine-palladium dichloride, preferably in the presence of a tri-lower alkyl amine, for example, trimethylamine, advantageously in the presence of Cu'-I, in a polar organic solvent such as N,N-di-lower alkyl-alkanoic acid amide, for example, dimethylformamide, a di-lower alkyl sulfoxide, for example, dimethylsulfoxide, or dioxan, at temperatures from appropriately 15° C to appropriately 120° C, preferably at the boil. When one of Yi and Y 2 denotes a reactive esterified hydroxy group and the other one represents a group of the formula Y3-X- in which Y 3 denotes a metallic group such as a halo-magnesium group, the reaction is preferably performed according to Grignard method, wherein the metallic intermediate is preferably formed in situ. When one of Yι. and Y 2 denotes lower alkanoyi and the other one represents lower alkyl, the intermolecular condensation of compounds of the formulae li and III is preferably performed according to the Shaw and Wagstaff method or one of its many modifications. When one of Y- and Y 2 denotes lower alkanoyi and the other one represents triarylphosphoranylidenemethyl , the condensation is preferably performed according to the well known Wittig olefin-building method, preferably by forming the phosphoranylidene component from a corresponding triarylphosphonium halide in situ, for example, by reacting the latter with a metal base, such as an alkalimetal hydride, such as sodium hydride, or with a metal-organic base, such as a lower alkyl metal compound, such as butyllithium, or with an alkali metal alkanoiate, for example, potassium tertiary butoxide, preferably in an inert organic solvent, such as an aromatic or arylaliphatic hydrocarbon, for example, benzene or toluene, at appropriately -10° C to appropriately 39° C, preferably first at 0° to 10° C and then at ambient temperature. Electrofugal groups Y 4 are, for example, esterified hydroxy groups, such as hydroxy groups esterified with an organic acid, for example, lower alkanoyloxy or hydroxy groups esterified with an anorganic acid, for example, halo groups, or tertiary amino groups, such as th-lower alkylamino groups, for example, trimethylamiπo, or lower-alkyleneamino, lower azaalkyleneamino, lower-oxyalkyieneamino or lower thiaalkyleneamino groups, such as pyrrolidino, piperidino, morpholino or thiomorpholino, or corresponding quaternary ammonium groups. The protection of functional groups by such protecting groups, the protecting groups themselves and the reactions for their removal are described, for example, in standard works. The elimination of H — Y 4 from compounds of formula IV can be performed in a customary manner. Thus, water or lower alkanoic acids may be eliminated by means of azeotropic distillation, for example, in toluene, advantageously under mild-acidic conditions. Hydrogen haiides may be removed under basic conditions such as reaction with an alkalimetal alkanoiate, preferably in the corresponding lower alkanol as a solvent or co-solvent, or by heating in the presence of a tertiary amine, such as a tri-lower alkylamine. The starting materials for the above described reactions are generally known. Novel starting materials can be obtained in manner analogous to the methods for the preparation of known starting materials. Compounds of formula I obtainable in accordance with the process can be converted into different compounds of formula I in customary manner, for example a free carboxy group may be esterified or amidated, an esterified or amidated carboxy group may be converted into a free carboxy group, an esterified carboxy group can be converted into an unsubstituted or substituted carbamoyl group, a free amino group can be acylated or alkylated, and a free hydroxy can be acylated. Also, compounds of the formula I can be oxidized by customary methods such as reaction with an organic peroxy acid, yielding the corresponding pyridine-N-oxide derivatives. Salts of compounds of formula I can also be converted in a manner known per se into the free compounds, for example by treatment with a base or with an acid. Resulting salts can be converted into different salts in a manner known per se. The compounds of formula I, including their salts, may also be obtained in the form of hydrates or may include the solvent used for crystallization. As a result of the close relationship between the novel compounds in free form and in the form of their salts, hereinbefore and hereinafter any reference to the free compounds and their salts is to be understood as including the free compounds, as well as the corresponding salts. In a compound of formula I the configuration at individual chirality centers can be selectively reversed. For example, the configuration of asymmetric carbon atoms that carry nucleophilic substituents, such as amino or hydroxy, can be reversed by second order nucleophilic substitution, optionally after conversion of the bonded nucleophilic substituent into a suitable nucleofugal leaving group and reaction with a reagent introducing the original substituent, or the configuration at carbon atoms having hydroxy groups can be reversed by oxidation and reduction, analogously to European Patent Application EP-A-0 236 734. Th e invention relates also to pharmaceutical compositions comprising compounds of formula I. The pharmacologically acceptable compounds of the present invention may be used, for example, in the preparation of pharmaceutical compositions that comprise an effective amount of the active ingredient together or in a mixture with a significant amount of inorganic or organic, solid or liquid, pharmaceutically acceptable carriers. The pharmaceutical compositions according to the invention are compositions for enteral, such as nasal, rectal or oral, or parenteral, such as intramuscular or intravenous, administration to warm-blooded animals (human beings and animals) that comprise an effective dose of the pharmacological active ingredient alone or together with a significant amount of a pharmaceutically acceptable carrier. The dose of the active ingredient depends on the species of warm-blooded animal, body weight, age and individual condition, individual pharmacokinetic data, the disease to be treated and ihe mode of administration. The pharmaceutical compositions comprise from approximately 1 % to approximately 95%, preferably from approximately 20% to approximately 90%, active ingredient. Pharmaceutical compositions according to the invention may be, for example, in unit dose form, such as in the form of ampoules, vials, suppositories, dragees, tablets or capsules. The pharmaceutical compositions of the present invention are prepared in a manner known per se, for example by means of conventional dissolving, lyophilizing, mixing, granulating or confectioning processes. The doses to be administered to warm-blooded animals, for example human beings, of, for example, approximately 70 kg body weight, especially the doses effective in disorders caused by or associated with irregularities of the glutamatergic signal transmission, are from approximately 3 mg to approximately 3 g, preferably from approximately 10 mg to approximately 1 g, for example approximately from 20 mg to 500 mg, per person per day, divided preferably into 1 to 4 single doses which may, for example, be of the same size. Usually, children receive about half of the adult dose. The dose necessary for each individual can be monitored, for example by measuring the serum concentration of the active ingredient, and adjusted to an optimum level. The following non-limiting Examples serve to illustrate the invention; temperatures are given in degrees Celsius, pressures in mbar. EXAMPLE 1 3-[2-(6-Methylpyridin-2-yl)-vinyl]-benzonitrile A solution of 2,6-dimethyl pyridine (4.2ml, 36.28 mMol), 3-cyanobenzaldehyde (4.95g, 37.74 mMol) in acetic anhydride (6.85 ml) is heated under reflux for 16 hours. The acetic anhydride is then evaporated in vacuo and the residue purified on column chromatography (silica gel 400g). The column is first eluted with toluene (400 ml) and then with toluene/ethyl acetate 95:5. The fractions containing the desired compound are combined, evaporated in vacuo. The solid residue is recrystallized from methylene chloride/hexane and 3.18 g of white crystals are isolated, (melting point: 91 -92°). EXAMPLE 2: 2-[2-(6-Methyl-pyridin-2-yl)-vinyl]-benzonitrile A solution of 2,6-dimethyl pyridine (5.8 ml, 50 mMol), 2-cyanobenzaldehyde (6.81 g, 52 mMol) in acetic anhydride (9.5 ml) is heated under reflux for 16 hours. The acetic anhydride is then evaporated in vacuo and the residue purified on column chromatography (silica gel 400g). The column is first eluted with toluene (400 ml) and then with toluene/ethyl acetate 95:5. The fractions containing the desired compound are combined, evaporated in vacuo. The solid residue is recrystallized from methylene chloride/diisopropyl ether and white crystals are isolated, (melting point: 113-114°). EXAMPLE 3 2-Methyl-6-[2-(pyridin-4-yl)-vinyl]-pyridine A solution of 2,6-dimethyl pyridine (5.8 ml, 50 mMol), pyridine-4-carba!dehyde (4.9 ml, 52 mMol) in acetic anhydride (9.5 ml) is heated under reflux for 16 hours. The acetic anhydride is then evaporated in vacuo and the residue purified on column chromatography (silica gel 900g). The column is first eluted with toluene/acetone 4:1 (5 L), then with toluene/acetone 3:1 (5 L) and finally with toluene/acetone 2:1 (15 L). The fractions containing the desired compound are combined, evaporated in vacuo. The solid residue is recrystallized from methylene chloride/diisopropyl ether and 0.956 g of white crystals are isolated, (melting point: 72-73°C). EXAMPLE 4 2-Methyl-6-[2-(pyridin-3-yl)-vinyl]-pyridine A solution of 2,6-dimethyl pyridine (5.8 ml, 50 mMol), pyridine-3-carbaldehyde (4.9 ml, 52 mMol) in acetic anhydride (9.5 ml) is heated under reflux for 10 hours. The acetic anhydride is then evaporated in vacuo and the residue purified on column chromatography anhydride is then evaporated in vacuo and the residue purified on column chromatography (silica gel 900g). The column is first eluted with toluene/acetone 9:1 (7 L), then with toluene/acetone 4:1 (5 L) and finally with toluene/acetone 2:1 (5 L). The fractions containing the desired compound are combined, evaporated in vacuo. The solid residue is recrystallized from methylene chloride/diisopropyl ether and 4.28 g of a colorless oil which solidify upon standing at 6-8°C. EXAMPLE 5 2-[2-(3-3romophenyl)ethynyl]-6-methyl-pyridine 1.2 g (2.8 mMol) of 2-[1 ,2-dibromo-2-(3-bromophenyl)-ethyl]-6-methyl-pyridine are dissolved in 10 ml of ethanol. 0.9 g (16.1 mMol) of potassium hydroxide (powder) are added, and the resulting suspension is heated under reflux for 4 hours. The suspension is then cooled to room temperature, poured into 100 ml of brine and extracted thrice with 30 ml each of t- butyl methyl ether. The combined organic phases are washed with 30 ml of brine, dried over Sodium sulfate, filtrated and evaporated in vacuo. 0.720 g of the title compound are obtained as a colorless oii crystallizing on standing; melting point 60-61 °. The starting material can be obtained as follows: a) 2-r2-(3-Bromophenyl)-vinvn-6-methyl-pyridine A solution of 24 ml (200 mMol) of 2,6-dimethyl pyridine and 25.6 ml (207 mMol) of 3- bromobenzaldehyde in 38 ml of acetic anhydride is heated under reflux for 7.5 hours. The acetic anhydride is then evaporated in vacuo, and the residue is dissolved in 500 ml of 4N hydrochloric acid and twice extracted with 200 ml each of hexane. The water phase is then extracted four times with 300 ml each of tert.-butyl methyl ether. The combined organic phases are washed twice with 300 ml each of a saturated solution of NaHCO 3 in water, then once with 300 ml of brine (300 ml), dried over sodium sulfate, filtrated and evaporated in vacuo yielding 4.2 g of the title compound as colorless crystals of melting point 58-59°. b) 2-H ,2-dibromo-2-(3-bromoohenyl)-ethvπ-6-methyl-pyridine 1 g (3.6 mMol) of 2-(3-Bromo-phenylethynyl)-6-methyl-pyridine are dissolved in 5 ml of carbon tetrachloride, and the solution is heated to 55-60°. A solution of 0.23 ml (4.4 mMol) of bromine Br2 in 1 ml of carbon tetrachloride is added dropwise. The reaction mixture is maintained at 55-60° for 30 minutes and then cooled to room temperature. The resulting precipitate is collected by filtration and dried in vacuo. 1.3 g of the title compound in form of yellow crystals of melting point 164-166are isolated. EXAMPLE 6 3-[2-(6-Methylpyridin-2-yl)ethynyl]-benzonithle A mixture of 1 g (8.54 mMol) 2-ethynyI-6-methyl-pyridine (prepared in analogy to D. E. Ames et al., Synthesis, 1981 , p. 364-δ), 2.3 g (12.8 mMol) 3-bromo-benzonitrile, 0.47 g (0.7 mMol ) bis-(triphenylphosphine)-palladium-ll-chloride, 80 mg (0.41 mMol) cuprous iodide and 1.63 ml (1 δ mMol) triethylamine in 10 ml dimethylformamide is stirred for 3 hours at 90° C. The reaction mixture is cooled to ambient temperature, poured into water and extracted with dichloromethane. The organic layer is dried over sodium sulfate, filtered, evaporated to dryness and the residue is purified by chromatography on silica gel with hexane/ethyl acetate (4:1) as eluant. Crystallization from hexane of the obtained product affords 0.53 g (28.4 %) of the title compound as brown crystals, melting point 120-3° C. EXAMPLE 7 In analogous manner to Example 1 (when X is alkenylene) or Example 5 (when X is alkynyiene), the following compounds of formula I can be prepared: (dec = decomposition)

Claims: Claims: 1. A 2-arylalkenyl- , 2-heteroarylalkenyl-, 2-arylalkynyl-, 2-heteroarylalkynyi-, 2-arylazo- and 2-heteroarylazo- pyridine or a pharmaceutically acceptable salt thereof, for use in the treatment of disorders associated with irregularities of the glutamatergic signal transmission, and of nervous system disorders mediated full or in part by mGluRδ. 2. A 2-arylalkenyl- , 2-heteroarylalkenyl-, 2-arylalkynyl-, 2-heteroarylalkynyl-, 2-arylazo- and 2-heteroarylazo- pyridine or a pharmaceutically acceptable salt thereof, for use in the treatment of epilepsy, cerebral ischemia, ischemic diseases of the eye, muscle spasms, convulsions, pain, acute, traumatic and chronic degenerative processes of the nervous system and psychiatric diseases. 3. A compound of formula I wherein R- denotes hydrogen, lower alkyl, hydroxy-lower alkyl, lower alkyl-amino, piperidino, carboxy, esterified carboxy, amidated carboxy, unsubstituted or lower alkyl-, lower alkoxy-, halo- and/or trifluoromethyl-substituted N-lower-a!kyl-N-phenylcarbamoyl, lower alkoxy, halo-lower alkyl or halo-lower alkoxy, R 2 denotes hydrogen, lower alkyl, carboxy, esterified carboxy, amidated carboxy, hydroxy-lower alkyl, hydroxy, lower alkoxy or lower alkanoyloxy, 4-(4-fluoro-benzoyl)- piperidin-1 -yl-carboxy, 4-t.-butyloxycarbonyi-piperazin-1 -yl-carboxy, 4-(4-azido-2- hydroxybenzoyl)-piperazin-1 -yl-carboxy or 4-(4-azido-2-hydroxy-3-iodo-benzoyl)- piperazin-1 -yl-carboxy, R 3 represents hydrogen, lower alkyl, carboxy, lower alkoxy-carbonyl, lower alkyl- carbamoyl, hydroxy- lower alkyl, di- lower alkyl- aminomethyl, morpholinocarbonyl or 4-(4-fluoro-beπzoyl)-piperidin-1 -yl-carboxy, R 4 represents hydrogen, lower alkyl, hydroxy, hydroxy-lower alkyl, amino-lower alkyl, lower alkylamino-lower alkyl, di-lower alkylamino-lower alkyl, unsubstituted or hydroxy- substituted lower alkyleneamino-lower alkyl, lower alkoxy, lower alkanoyloxy, amino- lower alkoxy, lower alkylamino-lower alkoxy, di-lower alkylamino-lower alkoxy, phthalimido-lower alkoxy, unsubstituted or hydroxy- or 2-oxo-imidazolidin-1 -yl- substituted lower alkyleneamino-lower alkoxy, carboxy, esterified or amidated carboxy, carboxy-lower-alkoxy or esterified carboxy-lower-aikoxy, X represents an optionally halo-substituted lower alkenylene or alkynyiene group bonded via vicinal unsaturated carbon atoms or an azo (-N=N-) group, and R 5 denotes an aromatic or heteroaromatic group which is unsubstituted or substituted by one or more substituents selected from lower alkyl, halo, halo-lower alkyl, halo- lower alkoxy, lower alkenyl, lower alkynyl, unsubstituted or lower alkyl-, lower alkoxy-, halo- and/or trifluoromethyl-substituted phenyl, unsubstituted or lower alkyl-, lower alkoxy-, halo- and/or trifluoromethyl-substituted phenyl-lower alkynyl, hydroxy, hydroxy-lower alkyl, lower alkanoyloxy-lower alkyl, lower alkoxy, lower alkenyloxy, lower aikylenedioxy, lower alkanoyloxy, amino-, lower alkylamino-, lower alkanoylamino- or N-lower alkyl-N-lower alkanoylamino-lower alkoxy, unsubstituted or lower alkyl- lower alkoxy-, halo- and/or trifluoromethyl-substituted phenoxy, unsubstituted or lower alkyl- lower alkoxy-, halo- and/or trifluoromethyl-substituted phenyl-lower alkoxy, acyl, carboxy, esterified carboxy, amidated carboxy, cyano, carboxy-lower alkylamino, esterified carboxy-lower alkylamino, amidated carboxy- lower alkylamino, phosphono-lower alkylamino, esterified phosphono-lower alkylamino, nitro, amino, lower alkylamino, di-lower alkylamino, acylamino, N-acyl-N- lower alkylamino, phenylamino, phenyl-lower alkylamino, cycloaikyl-lower alkylamino or heteroaryl-lower alkylamino each of which may be unsubstituted or lower alkyl- lower alkoxy-, halo- and/or trifluoromethyl-substituted, in free form or in form of a photoaffinity ligand, a radioactive marker, an N-oxide or a pharmaceutically acceptable salt, for use in the treatment of disorders associated with irregularities of the glutaminergic signal transmission, and of nervous system disorders mediated full or in part by mGluRδ. 4. The use of a compound according to claim 3, in the treatment of disorders associated with irregularities of the glutamatergic signal transmission, and of nervous system disorders mediated full or in part by mGluRS. δ. The use of a compound according to claim 3, for the manufacture of a pharmaceutical composition designed for the treatment of disorders associated with irregularities of the glutamatergic signal transmission, and of nervous system disorders mediated full or in part by mGluRδ. 6. A compound of formula I wherein Ri denotes hydrogen, lower alkyl, hydroxy-lower alkyl, lower alkyl-amino, piperidino, carboxy, esterified carboxy, amidated carboxy, unsubstituted or lower alkyl-, lower alkoxy-, halo- and/or trifluoromethyl-substituted N-lower-alkyl-N-phenylcarbamoyl, lower alkoxy, halo-lower alkyl or halo-lower alkoxy, R 2 denotes hydrogen, lower alkyl, carboxy, esterified carboxy, amidated carboxy, hydroxy-lower alkyl, hydroxy, lower alkoxy or lower alkanoyloxy, 4-(4-fluoro-benzoyl)- piperidin-1 -yl-carboxy, 4-t.-butyloxycarbonyl-piperazin-1 -yl-carboxy, 4-(4-azido-2- hydroxybenzoyl)-piperazin-1 -yl-carboxy or 4-(4-azido-2-hydroxy-3-iodo-benzoyl)- piperazin-1 -yl-carboxy, R 3 represents hydrogen, lower alkyl, carboxy, lower alkoxy-carbonyl, lower alkyl- carbamoyl, hydroxy- lower alkyl, di- lower alkyl- aminomethyi, morpholinocarbonyl or 4-(4-fluoro-benzoyl)-piperidin-1 -yl-carboxy, R 4 represents hydrogen, lower alkyl, hydroxy, hydroxy-lower alkyl, amino-lower alkyl, lower alkylamino-lower alkyl, di-lower alkylamino-lower alkyl, unsubstituted or hydroxy- substituted lower alkyleneamino-lower alkyl, lower alkoxy. lower alkanoyloxy, amino- lower alkoxy, lower alkylamino-lower alkoxy, di-lower alkylamino-lower alkoxy, phthalimido-lower alkoxy, unsubstituted or hydroxy- or 2-oxo-imidazolidin-1 -yl- substituted lower alkyleneamino-lower alkoxy, carboxy, esterified or amidated carboxy, carboxy-lower-alkoxy or esterified carboxy-iower-alkoxy, X represents an optionally halo-substituted lower alkenyiene or alkynyiene group bonded via vicinal unsaturated carbon atoms or an azo (-N=N-) group, and R 5 denotes an aromatic or heteroaromatic group which is unsubstituted or substituted by one or more substituents selected from lower alkyl, halo, halo-lower alkyl, halo- lower alkoxy, lower alkenyl, lower alkynyl, unsubstituted or lower alkyl-, lower alkoxy-, halo- and/or trifluoromethyl-substituted phenyl, unsubstituted or lower alkyl-, lower alkoxy-, halo- and/or trifluoromethyl-substituted phenyl-lower alkynyl, hydroxy, hydroxy-lower alkyl, lower alkanoyloxy-lower alkyl, lower alkoxy, lower alkenyloxy, lower alkylenedioxy, lower alkanoyloxy, amino-, lower alkylamino-, lower alkanoylamino- or N-lower alkyl-N-lower alkanoylamino-lower alkoxy, unsubstituted or lower alkyl- lower alkoxy-, halo- and/or trifluoromethyl-substituted phenoxy, unsubstituted or lower alkyl- lower alkoxy-, halo- and/or trifiuoromethyi-substituted phenyl-lower alkoxy, acyi, carboxy, esterified carboxy, amidated carboxy, cyano, carboxy-lower alkylamino, esterified carboxy-lower alkylamino, amidated carboxy- lower alkylamino, phosphono-lower alkylamino, esterified phosphono-lower alkylamino, nitro, amino, lower alkylamino, di-lower alkylamino, acylamino, N-acyl-N- lower alkylamino, phenylamino, phenyl-lower alkylamino, cycloalkyl-lower alkylamino or heteroaryl-lower alkylamino each of which may be unsubstituted or lower alkyl- lower alkoxy-, halo- and/or trifluoromethyl-substituted, in free form or in form of a photoaffinity ligand, a radioactive marker, an N-oxide or a pharmaceutically acceptable salt, provided that, when R 3 is hydrogen, a) in compounds of the formula I in which R^ R 2 and R 4 are hydrogen, R 5 is different from phenyl, monohalophenyl, 2,4- and 3,4-dichlorophenyl, 3- and 4- trifluoromethylphenyl, methylphenyl, 3,4- and 2,δ-dimethylphenyl, 4-isopropylphenyl, 3,δ-di-tert.-butylphenyl, methoxyphenyl, 3,4-dimethoxyphenyl, 2,4,6- and 3,4,5- trimethoxyphenyl, hydroxyphenyl, 3,6-dihydroxyphenyl, 4-hydroxy-3,δ-dimethyl- phenyl, 3-hydroxy-4-methoxy- and 4-hydroxy-3-methoxy-phenyl, 4-hydroxy-(3-methyl- 5-tert.-butyl-, 2- and 4-acetylaminophenyl, 3,5-diisopropyi- and 3,5-di-tert.- butyl)phenyl, 4-carboxy- and 4-ethoxycarbonyiphenyl, 4-cyanophenyl, 3- methoxycarbonylphenyl, 3-carboxy-5-methoxy-phenyl, 2-pyridinyl, 5-chloro-2-pyridinyl and 6-methyl-2-pyridinyl when X denotes ethenylene, or R 5 is different from phenyl, 4- methylphenyl, 4-methoxyphenyl, 4-bromophenyl and 2- and 4-chlorophenyl when X denotes 1 ,2-propylene attached to R 5 in 2-position, or R 5 is different from phenyl, 2- and 4-chlorophenyl and 3-methoxyphenyl when X denotes 1 ,2-propyiene attached to R 5 in 1 -position, or R 5 is different from 4-methoxyphenyl when X denotes 2,3-but-2- enylene or 1 ,2-but-1 -enylene attached to R 5 in 2-position, or R 5 is different from 4- methoxyphenyl and 4-isopropyphenyi when X denotes 2,3-pent-2-enyiene attached to R 5 in 3-position, or R 5 is different from phenyl, 4-methylphenyl, methoxyphenyl and 4- hydroxyphenyl when X denotes 3,4-hex-3-enyiene; b) in compounds of the formula I in which R-i is methyl and R 2 and R 4 are hydrogen, R 5 is different from phenyl, 3-methylphenyl, 2-methoxyphenyl, 2-chiorophenyl, 4- cyanophenyl, , 2-pyridinyl and 6-methyl-2-pyridinyl when X denotes ethenylene; c) in compounds of the formula I in which R-i and R 2 are hydrogen and R is carboxy, R 5 is different from phenyl, 3-methylphenyl, 4-methoxyphenyl and 4-bromophenyl when X denotes ethenylene; d) in compounds of the formula I in which Ri and R 2 are hydrogen and R is methyl, R is different from phenyl, 3-methoxy-, 4-methoxy- and 3,4-dimethoxyphenyl, 2- chloro- and 2,4-dichlorophenyl and 6-methyl-pyrid-2yl when X denotes ethenylene or R 5 is different from phenyl when X is 1 ,2-prop-1-enylene attached to R 5 in 2-position; e) in compounds of the formula I wherein R- \ and R 2 are hydrogen and R 4 is 2- cimethylaminoethoxycarbonyl or 3-dimethylaminopropyloxycarbonyl, R 5 is different from 4-methoxyphenyl when X denotes ethenylene; f) in compounds of the formula I in which R-i and R 2 are hydrogen and R 4 is 2- dimethoxyethoxy, R 5 is different from phenyl, 4-methylphenyl and 4- methoxycarbonylphenyl when X denotes ethenylene; g) R 5 is different from phenyl when R-i and R 2 are hydrogen and R 4 is hydroxy or ethoxycarbonyl, or when Ri and R 2 are hydrogen and R 4 is hydroxy, or when R-i is methyl, R 2 is hydrogen and R 4 is methoxy, or -i is but-1 -enyl, R 2 is hydrogen and R is hydrogen, or Ri is hydrogen and R is 2-dimethoxyethoxy, and X is, in each case, ethenylene, and provided that, when R 3 is hydrogen and X is ethynylene, a') R 5 is different from phenyl, 2- and 4-nitrophenyl, 4-aminophenyl, 4-chlorophenyl, 4- methylphenyl, 4-methoxyphenyl, 4-ethoxycarbonylphenyl, 5-formyl-2-methoxy-phenyl, 5-carboxy-2-methyo-phenyi and pyridyl when R^ R 2 and R 4 are hydrogen; b') in compounds of the formula I in which R 2 and R 4 are hydrogen, R 5 is different from phenyl, 3-methyiphenyl. 6-methylpyridin-2-y! and 2-methoxyphenyl when R, is methyl, R 5 is different form 6-bromopyridin-2-yl when R^ is bromo, and R 5 is different form 6- hexyioxypyridin-2-yl when R-i denotes hexyloxy; c') in compounds of the formula I wherein Ri and R 4 are hydrogen, R 5 is different from phenyl, 4-aminophenyl and 4-propylphenyl when R 2 is methyl, R 5 is different from phenyl, 4-cyanophenyi and 4-pentylphenyl when R 2 is ethyi, R 5 is different form 3- cyano-4-ethoxy-phenyland 3-bromo-4-methoxy-phenyl when R 2 is butyl, R s is different from 4-methoxyphenyl and 4 butyloxyphenyl when R 2 is pentyl, R 5 is different form 4- ter.-butylphenyl, 3-tert.-butyl-4-hydroxy-phenyl, 4-tert.-butyl-3-hydroxy-phenyl,and 4- hexyloxyphenyl when R 2 is carboxy, R 5 is different from phenyl when R 2 is methoxycarbonyi or methylcarbamoyl, R 4 is different form 3-tert.-butylphenyl, 3-tert.- butyl-4-hydroxy-phenyl and 4-(4-methylpentyl)phenyl when R 2 is ethoxycarbonyl, and R 5 is different from 4-pentyloxyphenyl when R 2 is 2-methylbutyioxycarbonyl; d') in compounds of the formula I wherein Ri and R 2 are hydrogen, R 5 is different from phenyl v/hen R is hydroxy, methyl, ethyl, carboxy, methoxycarbonyi or carbamoyl. A compound according to claim 6, wherein X represents an optionally halo-substituted (C 2 . 4 )alkenyiene or alkynyiene group bonded via vicinal unsaturated carbon atoms, Ri is hydrogen, (Cι. 4 ) alkyl, (Cι. 4 )alkoxy, hydroxy(d. 4 )alkyl, cyano, ethynyl, carboxy, (d. )alkoxycarbonyl, di(C 1 . 4 )alkylamino, (d. 6 )alkylaminocarbonyl, trifluoromethylphenylaminocarbonyl, R 2 is hydrogen, hydroxy, (C 1-4 ) alkyl, hydroxy (Cι. 4 ) alkyl, (Cι. 4 ) alkoxy, carboxy, (C 2 . 5 )alkanoyloxy, (Cι_ 4 ) alkoxycarbonyl, di(Cι. 4 )alkylamino(Cι. )alkanoyl, di(Cι. 4 )alkyiaminomethyl, 4-(4-fluoro-benzoyl)-piperidin-1 -yl-carboxy, 4-t.- butyloxycarbonyl-piperazin-1 -yl-carboxy, 4-(4-azido-2-hydroxybenzoyl)- piperazin-1 -yl-carboxy or 4-(4-azido-2-hydroxy-3-iodo-benzoyl)-piperazin-1 -yl- carboxy, R 3 is hydrogen, (Cι. ) alkyl, carboxy, (Cι. 4 )alkoxycarbonyl, (d. 4 )alkylcarbamoyl, hydroxy(Cι. 4 )alkyl, di(Cι- )alkylaminomethyl, morpholinocarbonyl or 4-(4-fiuoro- benzoy!)-piperidin-1 -yl-carboxy, R 4 is hydrogen, hydroxy, (Cι. 4 )alkoxy, carboxy, (C 2 . 5 )alkanoyloxy, (Cι. )alkoxycarbonyl, amino(Cι. )alkoxy, di(Cι- )alkylamino(d- 4 )alkoxy, di(Cι. )alkylamino(Cι. 4 )alkyl, carboxy (d. 4 )alkylcarbonyl, (d-*)alkoxycarbonyl- (Cι. 4 )aikoxy, hydroxy(Cι- 4 )alkyl, di(d. 4 )alkylamino(d- 4 )alkoxy, m-hydroxy-p- azidophenylcarbonylamino(Cι- 4 )alkoxy, and R 5 is a roup of formula wherein R a and R b independently are hydrogen, hydroxy, halogen, nitro, cyano, carboxy, (d- 4 )alkyl, (Cι. 4 )alkoxy, hydroxy(Cι. 4 )alkyl, (d. 4 )alkoxycarbonyl, (C 2 . 7 )alkanoyl, (C 2 . 5 )alkanoyloxy, (C 2 - 5 )aikanoyloxy(Cι. 4 )alkyl, trifiuoromethyl, trifluoromethoxy, trimethylsilylethynyl, (C 2 . 5 )alkynyl, amino, azido, amino (Cι. 4 )alkoxy, (C 2 . 5 )alkanoylamino(Cι. 4 )alkoxy, (Cι. 4 )alkylamino(Cι. 4 )alkoxy, di(C 1-4 )alkyl- amino(Cι. 4 )alkoxy, (d. 4 )alkylamino, di(Cι. )alkylamino, monohalobenzylamino, thienylmethylamino, thienylcarbonylamino, trifluoromethylphenylaminocarbonyl, tetrazolyl, (C 2 . 5 )alkanoylamino, benzyicarbonylamino, (Cι- 4 )alkylamino- carbonylamino, (Cι- 4 )alkoxycarbonyl-aminocarbonyiamino or (Cι. 4 )alkylsuifonyl, R c is hydrogen, fluorine, chlorine, bromine, hydroxy, (Cι -4 )alkyl, (C 2 . 5 )alkanoyloxy, (d. 4 )aikoxy or cyano, and R d is hydrogen, halogen or (C 1-4 )alkyl. A compound according to claim 6, wherein Ri is hydrogen, (Cι- ) alkyl, (d- 4 )alkoxy, cyano, ethynyl or di(Cι. 4 )alkylamino, R 2 is hydrogen, hydroxy, carboxy, (C ) alkoxycarbonyl, di(Cι. 4 )alkylaminomethyl, 4-(4-fluoro-benzoyl)-piperidin-1 -yl-carboxy, 4-t.-butyloxycarbonyl-piperazin-1 -yl- carboxy, 4-(4-azido-2-hydroxybenzoyl)-piperazin-1 -yl-carboxy or 4-(4-azido-2- hydroxy-3-iodo-benzoyl)-piperazin-1 -yl-carboxy, R 3 is as defined in claim 7, R 4 is hydrogen, hydroxy, carboxy, (C 2 . 5 )alkanoyloxy, (Cι. 4 )alkoxycarbonyl, amino (Cι_ )alkoxy, di(Cι. 4 )alkylamino(Cι- 4 )alkoxy, di(Cι. 4 )alkylamino(Cι. 4 )alkyl or hydroxy(Cι. 4 )alkyl, and R s is a group of formula wherein R a and R b independently are hydrogen, halogen, nitro, cyano, (d. )alkyi, (Cι 4 )alkoxy, trifiuoromethyl, trifluoromethoxy or (C 2 . 5 )aikynyl, and R c and R are as defined in claim 7. A compound according to claim 6, selected from -[2-(6-Methylpyridin-2-yl)-vinyl]-benzonitrile -[2-(6-Methyl-pyridin-2-yl)-vinyl]-benzonitrile 2-Methyl-6-[2-(pyridin-4-yl)-vinyl]-pyridine 2-Methyl-6-[2-(pyridin-3-yl)-vinyl]-pyridine 2-[2-(3-Bromophenyi)ethynyl]-6-methyl-pyridine 3-[2-(6-Methylpyridin-2-yl)ethynyl]-benzonitrile 2-Styryl-pyridin-3-ol 2-Methyl-6-[2-(3-nitro-phenyl)-vinyl]-pyridine Acetic acid 6-[2-(2-chloro-phenyl)-vinyl]-pyridin-3-yl ester 6-[2-(2-Chloro-phenyl)-vinyl]-pyridin-3-ol Acetic acid 2-[2-(2-chloro-phenyl)-vinyl]-pyridin-3-yl ester 2-[2-(2-Chloro-phenyl)-vinyl]-pyridin-3-ol 6-Methyl-2-styryl-pyridin-3-ol Acetic acid 2-[2-(2-chloro-phenyl)-vinyl]-6-methyl-pyridin-3-yl ester 2-[2-(2-Chloro-phenyl)-vinyl]-6-methyl-pyridin-3-ol (Z)-6-Methyl-2-styryl-pyridin-3-ol 2-[2-(2-Nitro-phenyl)-vinyl]-pyridine Acetic acid 2-[2-(4-chloro-phenyl)-vinyl]-6-methyl-pyridin-3-yl ester Acetic acid 6-[2-(4-chloro-phenyl)-vinyl]-2-methyl-pyridin-3-yl ester 2-[2-(4-Chloro-phenyl)-vinyl]-6-methyl-pyridin-3-ol 6-[2-(4-Chloro-phenyl)-vinyl]-2-methyl-pyridin-3-ol Acetic acid 6-methyl-2-[2-(2-nitro-phenyl)-vinyl]-pyridin-3-yl ester 6-Methyl-2-[2-(2-nitro-phenyl)-vinyl]-pyridin-3-ol Acetic acid 2-methyl-6-[2-(2-nitro-phenyl)-vinyl]-pyridin-3-yl ester 2-Methyl-6-[2-(2-nitro-phenyl)-vinyl]-pyridin-3-ol Acetic acid 2-[2-(3-chloro-phenyl)-vinyl]-6-methyl-pyridin-3-yl ester Acetic acid 6-[2-(3-chloro-phenyl)-vinyl]-2-methyl-pyridin-3-yl ester 2-[2-(3-Chloro-phenyl)-vinyl]-6-methyl-pyridin-3-ol 6-[2-(3-Chloro-phenyl)-vinyl]-2-methyl-pyridin-3-ol (Z)-(6-Styryl-pyridin-2-yl)-methanol (Ξ)-(6-Styryl-pyridin-2-yl)-methanol Dimethyl-[3-(6-methyl-2-styryl-pyridin-3-yloxy)-propyl]-amine; 2-Methyl-6-styryl-pyridine 1 -oxide 2-Styryl-pyridine 1 -oxide (E)-6-Metnyl-2-(2-pyhdin-2-yl-vinyl)-pyridin-3-ol (Z)-6-Methyl-2-(2-pyridin-2-yl-vinyl)-pyridin-3-ol; 6-Styryl-pyridine-2-carbonitrile 2-[2-(2,6-Dichloro-phenyl)-vinyl]-6-methyl-pyridine 3-Methoxy-6-methyl-2-styryl-pyridine 6-Styryl-pyridine-2-carboxyiic acid amide 2-[2-(6-Methyl-pyridin-2-yl)-vinyl]-benzonitri!e 6-Styryl-pyridine-2-carboxylic acid; 6-Styryl-pyridine-2-carboxylic acid methyl ester Acetic acid 2-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl ester 2-[2-(6-Methyl-pyridin-2-yl)-vinyl]-pheπol Acetic acid 2-methoxy-4-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl ester 2-[2-(3-Chloro-phenyl)-vinyl]-6-methyl-pyridine 2-[2-(4-Chloro-phenyl)-vinyl]-6-methyl-pyridine 2-[2-(2-Chloro-phenyl)-vinyl]-5-ethyl-pyridine 1 -(6-Styryl-pyridin-2-yl)-ethanone 6-[2-(2-Chloro-phenyl)-vinyl]-2-methyl-nicotinic acid ethyl ester 2-[2-(2-Chloro-phenyl)-vinyl]-6-methyl-nicotinic acid ethyl ester 2-[2-(6-Methyl-pyridin-2-yl)-vinyl]-benzoic acid; 3-[2-(6-Methyl-pyridin-2-yl)-vinyl]-benzoic acid 4-[2-(6- ethyl-pyridin-2-yl)-vinyl]-benzoic acid 3-[2-(6-Methyl-pyridin-2-yl)-vinyl]-benzoic acid methyl ester 4-[2-(6-Methyl-pyridin-2-yl)-vinyl]-benzoic acid methyl ester 2-Methoxy-4-[2-(6-methyl-pyridin-2-yi)-vinyl]-phenol {3-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phenyl}-methanol; 6-Styryl-pyridine-2-carboxylic acid .tert.-butylamide 2-(2-Bromo-2-phenyl-vinyl)-6-methyl-pyridine; 6-Styryl-pyridine-2-carboxylic acid hexylamide; 6-[2-(2-Chloro-phenyl)-vinyl]-2-methyl-nicotinic acid 2-[2-(2-Chloro-phenyl)-vinyl]-6-methyl-nicotinic acid 2-[2-(3,5-Dichloro-phenyl)-vinyl]-6-methyl-pyridine 2-Methyl-6-[2-(3-trifluoromethyl-phenyl)-vinyl]-pyridine (E)-6-[2-(4-Pyridyl)vinyi]-2-picoline N,N-Diethyl-3-[2-(6-methyl-pyridin-2-yl)-vinyl]-benzamide; N,N-Diethyl-4-[2-(6-methyl-pyridin-2-yl)-vinyi]-benzamide; (E)-6-[2-(3-pyridyl)vinyl]-2-Picoline {2-[2-(2-Chloro-phenyl)-vinyl]-6-methyl-pyridin-3-yloxy}-acetic acid ethyl ester 3-[2-(6-Methyl-pyridin-2-yl)-vinyl]-.N.-(3-trifluoromethyl-phenyl)-benzamide; 4-[2-(6-Methyl-pyridin-2-yl)-vinyl]-.N.-(3-trifluoromethyl-phenyl)-benzamide 2-[2-(3-Nitro-phenyl)-vinyl]-pyridine 6-Styryl-pyridine-2-carboxyiic acid (3-trifluoromethyi-phenyl)-amide 2-(6-Styryl-pyridin-2-yl)-propan-2-ol 2-Methyl-6-(2-thiophen-2-yl-vinyl)-pyridine 2-[2-(3-Cyano-phenyl)-vinyi]-pyridine 2-[2-(3-Bromo-phenyl)-vinyl]-6-methyl-pyridine 2-[2-(3-Bromo-phenyl)-2-fluoro-vinyl]-6-methyl-pyridine 2-[2-(3,5-Dimethylphenyl)-2-fluoro-vinyl]-6-methyl-pyridine 2-[2-(2,3-Dimethoxy-phenyl)-vinyl]-6-methyl-pyridine 2-[2-(2,3-Dichloro-phenyl)-vinyl]-6-methyl-pyridine 2-[2-(3-Chloro-phenyl)-1 -methyl-vinyl]-pyridine {2-[2-(2-Chloro-phenyl)-vinyl]-6-methyl-pyridin-3-yl}-methanol 2-Methyl-6-[2-(3-trimethylsilanylethynyl-phenyl)-vinyl]-pyridine 2-[2-(3,4-Difluoro-phenyl)-vinyi]-6-methyl-pyridine 2-[2-(3-Ethynyl-phenyl)-vinyl]-6-methyl-pyridine 2-[2-(3,5-Difiuoro-phenyl)-vinyl]-6-methy!-pyridine 2-[2-(3-Fluoro-phenyl)-vinyl]-6-methyl-pyridine 2-[2-(3-Methoxy-phenyI)-vinyl]-6-methyl-pyridine 2- ethyl-6-[2-(3-phenoxy-phenyl)-vinyl]-pyridine 2-[2-(3-Benzyloxy-phenyl)-vinyl]-6-mathyl-pyridine 2-[2-(2,5-Difluoro-phenyl)-vinyl]-6-methyl-pyridine {2-[2-(2-Chloro-phenyl)-vinyl]-6-methyl-pyridin-3-yloxy}-acetic acid (3-{2-[2-(3-Chloro-phenyl)-vinyl]-6-methyl-pyridin-3-yloxy}-propyl)-dimethyl-amine {6-[2-(2-Chloro-phenyl)-vinyl]-2-methyl-pyridin-3-yl}-methanol 2-(3-Bromo-phenylethynyl)-6-methyl-pyridine 2-Methyl-6-{2-[3-(3-trifluoromethyl-phenoxy)-phenyl]-vinyl}-pyridine 2-[2-(3,5-Dimethoxy-phenyl)-vinyl]-6-methyl-pyridine 2-[2-(3-Chloro-phenyl)-vinyl]-3-methoxy-6-methyl-pyridine Acetic acid 4-bromo-2-[2-(6-methyi-pyridin-2-yl)-vinyl]-phenyl ester Acetic acid 3-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl ester 2-[2-(3,4-Dichloro-phenyl)-vinyl]-6-methyl-pyridine 4-Bromo-2-[2-(6-methyl-pyridiπ-2-yl)-viny!l-pheno! Acetic acid 2-[2-(3,5-dichloro-phenyl)-vinyl]-6-methyl-pyridin-3-yl ester Acetic acid 6-[2-(3,5-dichloro-phenyl)-vinyl]-2-methyi-pyridin-3-yl ester Acetic acid 2-[2-(3,5-dichloro-phenyl)-vinyi]-pyridin-3-yl ester 2- ethyl-6-(2-naphthalen-1-yl-vinyl)-pyridine 2-[2-(2,3-Dihydro-benzo[1 ,4]dioxin-6-yl)-vinyl]-6-methyl-pyridine 2-Methyl-6-(2-naphthalen-2-yl-vinyl)-pyridine 2-{2-[3-(3,5-Dichloro-phenoxy)-phenyl]-vinyi}-6-methyl-pyridine 2-[2-(3-Chloro-phenyl)-propenyl]-6-methyl-pyridine 2-[2-(2,3-Dihydro-benzofuran-5-yl)-vinyl]-6-methyl-pyridine 2-[2-(4-Fluoro-phenyl)-vinyl]-6-methyl-pyridine 2- ethyl-6-(2-o-tolyl-vinyl)-pyridine 2-Methyl-6-(2-p-tolyl-vinyl)-pyridine 2-Methyl-6-(2-p-tolyl-propenyl)-pyridine 3-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phenylamine (2,3-Dimethoxy-7-nitro-quinoxalin-5-yimethyl)-{3-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl}- amine N-{3-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phenyl}-acetamide N-{3-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phenyi}-2-phenyl-acetamide 2,2-Dimethyl-N-{3-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl}-propionamide Thiophene-2-carboxylic acid {3-[2-(6-methyI-pyridin-2-yl)-vinyl]-phenyl}-amide Cyclohexanecarboxylic acid {3-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl}-amide 1-(4-Bromo-phenyl)-3-{3-[2-(6-methyl-pyridin-2-yi)-vinyl]-phenyl}-urea 2-Methyl-6-[2-(4-nitro-phenyl)-vinyl]-pyridine 4-[2-(6- ethyl-pyridin-2-yl)-vinyl]-phenyiamine 2-[2-(3,5-Dichloro-phenyl)-vinyl]-6-methyl-pyridin-3-ol 6-[2-(3,5-Dichloro-phenyl)-vinyl]-2-methyl-pyridin-3-ol 2-[2-(3,5-Dichloro-phenyl)-vinyl]-pyridin-3-ol 2-[2-(6-Chloro-benzo[1 ,3]dioxol-5-yl)-vinyl]-6-methyl-pyridine 2-[2-(2,3-Difluoro-phenyl)-vinyl]-6-methyl-pyridine 2-[2-(3,4-Dichloro-phenyl)-propenyl]-6-methyl-pyridine 2-[2-(3,5-Bis-trifluoromethyl-phenyl)-vinyl]-6-meτhyl-pyridine Acetic acid 2-methoxy-6-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl ester 2-Methoxy-6-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenol 2-Methyl-6-[2-(2,3 1 6-trifluoro-phenyl)-vinyl]-pyridine 2-[2-(4-Fluoro-3-trifluoromethyl-phenyl)-vinyl]-6-methyl-pyridine 2- ethyl-6-(2,3,6-trifluoro-phenylethynyl)-pyridine Acetic acid 4-chloro-2-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl ester Acetic acid 2,6-di-.tert.-butyl-4-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl ester 3-(6-Methyl-pyridin-2-ylethynyl)-benzamide Acetic acid 4-bromo-2-methoxy-6-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl ester 2-(6-Chloro-benzo[1 ,3]dioxol-5-ylethynyl)-6-mεthyl-pyridine 2-[2-(3,5-Dichioro-phenyl)-vinyl]-3-methoxy-6-methyl-pyridine 2-[2-(3,5-Dichloro-phenyl)-vinyl]-3-methoxy-pyridine 5-Azido-2-[2-(6-methyi-pyridin-2-yl)-vinyl]-phenol 2-[2-(Pyridin-3-yl)ethynyl]-6-methyl-pyridine N-{3-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phenyl}-succinamic acid 1-tert.-Butyl-3-{3-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl}-urea 5-({3-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phenylamino}-methyl)-7-nitro-1 ,4-dihydro-quinoxaline- 2,3-dione Tetrahydro-furan-2-carboxylic acid {3-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl}-amide (1 - 3-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phenylcarbamoyl}-2-ph8nyl-ethyl)-carbamic acid tert.- butyl ester ({3-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phenylcarbamoyl}-methyl)-carbamic acid tert.-butyl ester Diethyl-{3-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl}-amine Ethyl-{3-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl}-amine Ethyl-{3-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl}-amine 2-(2-Ethoxy-3,6-difluoro-phenylethynyl)-6-methyl-pyridine 2-(3,5-Difiuoro-phenylethynyl)-6-methyl-pyridine 2-(3-Fluoro-phenyiethynyl)-6-methyl-pyridine 2-[2-(3,5-Dimethyl-phenyl)-vinyl]-6-methyl-pyridine 2-[2-(3,4-Dimethoxy-phenyl)-vinyl]-6-methyl-pyridine 2-(3,4-Dichloro-phenylethynyl)-6-methyl-pyridine 2-(4-Ethoxy-3-trifluoromethyl-phenylethynyl)-6-methyl-pyridine 2-(4-Fluoro-phenylethynyl)-6-methyl-pyridine 2-Methyl-6-o-tolyiethynyl-pyridine 2-(3,4-Difluoro-phenylethynyl)-6-methyl-pyridine 2-Methyl-6-[2-(2,3,5-trich!oro-phεnyl)-vinyl]-pyridine 1-[3-(6-Methyl-pyridin-2-ylethynyl)-phenyl]-ethanone 2- ethyl-6-(3-trifluoromethyl-phenylethynyl)-pyridine 2- ethyl-6-(3-nitro-phenylεthynyl)-pyridinε 6-[2-(3,5-Dichloro-phenyl)-vinyl]-3-methoxy-2-methyl-pyridine {2-[2-(2-Chloro-phenyl)-vinyl]-6-methyl-pyridin-3-yl}-morphoiin-4-yi-methanone (3-{2-[2-(3,5-Dichloro-phenyl)-vinyl]-6-methyl-pyridin-3-yloxy}-propyl)-dimethyl-amine N-{4-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phenyl}-succiπamic acid N- 4-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phεnyl}-2-ph8nyl-acetamide ({4-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phenylcarbamoyl}-mεthyl)-carbamic acid .tεrt.-butyl ester 1-(tert.-Butyl-3-{4-[2-(6-mεthyl-pyridin-2-yi)-vinyl]-phεnyl}-urea {3-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phenyl}-thiophen-2-yimethyl-aminε hydrochloride salt Cyclohexylmethyl-{3-[2-(6-methyl-pyridin-2-yl)-vinyl]-phεnyl}-amine hydrochloride salt {4-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phenyl}-thiophen-2-ylmethyl-aminε Cyclohexylmεthyl-{4-[2-(6-mεthyl-pyridin-2-yl)-vinyl]-phenyl}-amine 2-Amino-N-{3-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl}-3-phenyl-propionamidε 2-Amino-N-{3-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl}-acetamide 2-Amino-N-{4-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl}-ac8tamid8 1-[1-({2-[2-(2-Chioro-phenyl)-vinyl]-6-methyl-pyridin-3-yloxy}-acetyl)-piperidin-4-yl]- imidazolidin-2-one (1-{4-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phenylamino}-ethyl)-phosphonic acid dimethyl ester 2-(3-Ethoxy-4-fluoro-phenylεthynyl)-6-methyl-pyridine 2-(3-Chloro-phenylethynyl)-6-methyl-pyridinε 1-(3-Pyridin-2-ylethynyl-phenyl)-ethanone 4-Chloro-2-[2-(6-mεthyl-pyridin-2-yl)-vinyi]-phenol 4-Bromo-2-methoxy-6-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenol 2-(2,5-Difluoro-phenylethynyl)-6-methyl-pyridine 2-(3,5-Dimethyl-phenylethynyl)-6-m8thyl-pyridinε 2-[2-(3,5-Dibromo-phenyl)-vinyl]-6-mεthyl-pyridine 3-(6- ethyl-pyridin-2-yiεthynyl)-benzonitrile 2-Methyl-6-[2-(pyrimidin-5-yl)-ethynyl]-pyridiπε (2-{2-[2-(3-Chloro-phenyl)-vinyl]-6-methyl-pyridin-3-yloxy}-ethyl)-dim8thyl-amine Acεtic acid 1-{4-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenyl}-ethyl ester 3-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phenol 3-(6-Methyl-pyridin-2-ylethynyl)-phenylamine .N.-[3-(6-Methyl-pyridin-2-ylethynyl)-phenyl]-2-phenyl-acetamide Thiophene-2-carboxylic acid [3-(6-methyl-pyridin-2-ylethynyl)-phenyl]-amide 2- ethyl-6-thiophen-2-ylethynyl-pyridine 3-(6- ethyl-pyridin-2-ylethynyl)-benzoic acid ethyl ester 2-(3,5-Dibromo-phenylethynyl)-6-methyl-pyridine {2-[2-(2-Chloro-phenyl)-vinyl]-6-methyl-pyridin-3-ylmεthyl}-dimεthyi-amine (3-{6-[2-(3-Chloro-phenyl)-vinyl]-2-methyl-pyridin-3-yloxy}-propyl)-dimethyl- 5-Azido-4-iodo-2-[2-(6-methyl-pyridin-2-yl)-vinyl]-phεnol 2,6-Di-tert.-butyl-4-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenol 1-{4-[2-(6-Mεthyl-pyridin-2-yl)-vinyl]-phεnyl}-εthanol 2-Methyl-6-[2-(pyrimidin-2-yl)-ethynyl]-pyridine [3-(6-Methyl-pyridin-2-ylethynyl)-phenyl]-phεnyl-methanone 6-(6-Methyl-pyridin-2-ylethynyl)-3,4-dihydro-1H-quinolin-2-one 2-(3-{2-[2-(3-Chloro-phenyl)-vinyl]-6-methyl-pyridin-3-yloxy}-propyl)-isoindole-1 ,3-dione 3-Methoxy-6-methyl-2-.m.-tolylethynyl-pyridine Acetic acid 2-[2-(6-methyl-pyridin-2-yl)-vinyl]-4-nitro-phenyl ester 6-(6-Methyl-pyridin-2-ylethynyl)-indan-1-one 2-Methyl-6-[2-(pyrazin-2-yl)-ethynyl]-pyridine N-Methyl-.N.-(3-{4-[2-(6-methyi-pyridin-2-yl)-vinyi]-phenoxy}-propyl)-acetamide 2-[2-(3,5-Bis-trifluoromεthyl-phenyl)-1-εthoxy-vinyl]-6-methyl-pyridine Acetic acid 2-phenyiethynyl-pyridin-3-yl ester Acetic acid 6-methyl-2-m-tolylethynyl-pyridin-3-yl ester Acetic acid 4-[2-(6-methyl-pyridin-2-yl)-vinyl]-2-nitro-phenyl εster 2-[2-(6-Methyl-pyridin-2-yl)-vinyl]-4-nitro-phenol Dimethyl-[3-(2-phenylethynyl-pyridin-3-yloxy)-propyi]-amine Dimethyl-(3-{4-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenoxy}-propyl)-amine 1-{4-[2-(6-Methyl-pyridin-2-yl)-vinyl]-phenyl}-ethanonε 2-(3-Fluoro-phenylethynyl)-quinoline Acetic acid 2-methyl-6-styryl-pyridin-3-yl ester 4-[2-(6-Mεthyl-pyridin-2-yl)-vinyl]-2-nitro-phenol 3-Ethoxy-4-[2-(6-methyl-pyridin-2-yl)-vinyl]-2-nitro-phenol 4-(6-Methyl-pyridin-2-ylethynyl)-2-nitro-phenol Acetic acid 2-[2-(6-methyl-pyridin-2-yl)-vinyl]-6-nitro-phenyl estεr Dimethyl-[3-(6-methyl-2-pheny!ethynyl-pyridin-3-yloxy)-propyl]-amine 2-Azido-4-[2-(6-mεthyl-pyridin-2-yl)-vinyl]-phenol Dimεthyl-[3-(6-mεthyl-2-.m.-tolylεthynyl-pyridin-3-yloxy)-propyl]-amine 2-(3- ethanesulfonyl-phenylethynyl)-6-methyl-pyridine 3-{2-[2-(3-Chloro-phenyl)-vinyl]-6-methyl-pyridin-3-yloxy}-propylamine 4-Azido-N-(3-{2-[2-(3-chloro-phenyl)-vinyl]-6-methyl-pyridin-3-yloxy}-propyl)-2-hydroxy- benzamide 3-[3-(3-Dimethylamino-propoxy)-6-methyl-pyridin-2-ylethynyl]-benzonitrile 5-(6-Methyl-pyridin-2-ylethynyl)-indan-1 -onε 2-Methyl-6-(2,3,5-trichloro-phεnylethynyl)-pyridinε 2-[2-(6-methyl-pyridin-3-yl)ethynyl]-6-methyl-pyridine Dim8thyl-{3-[6-methyl-2-(3-trifluoromethyl-phenylethynyl)-pyridin-3-yloxy]-propyl}-amine 2-[2-(6-methyι-pyridin-3-yl)εthynyl]-3-mεthoxy 6-methyl-pyridine hydrochloride salt 2-Methyl-6-(5,6,7,8-tetrahydro-naphthalen-2-ylethynyl)-pyridine 3-[2-(3-Chloro-phenylethynyl)-6-mεthyl-pyridin-3-yloxy]-propylamine (3-{4-Bromo-2-methoxy-6-[2-(6-methyl-pyridin-2-yl)-vinyl]-phenoxy}-propyl)-dimethyl-amine; [6-(3-Fluoro-phenylethynyl)-pyridin-2-yl]-dimethyl-amine e'-β-Fluoro-phenylethyny -SAS.e-tetrahydro^H-fl ^bipyridinyl {3-[2-(3-Chloro-phenylethynyl)-6-methyl-pyridin-3-yloxy]-propyl}-dimethyl-amine 4-Azido-N-{3-[2-(3-chloro-phenylethynyl)-6-methyl-pyridin-3-yloxy]-propyl}-2-hydroxy- benzamide 1-[3-(6-Methyl-pyridin-2-ylethynyl)-phenyl]-1H-[1 ,2,4]triazole-3-carboxylic acid ethyl ester 1 -[3-(6-Methyl-2-phenylethynyl-pyridin-3-yloxy)-propyl]-piperidin-3-ol 2-Ethynyl-6-(3-fluoro-phenylethynyl)-pyridine 3-Methyl-6-(6-methyl-pyridin-2-ylethynyl)-3H-bεnzooxazol-2-one 1 -[3-(6-Methyl-pyridin-2-ylεthynyl)-phenyl]-1 H-[1 ,2,4]triazole-3-carboxylic acid 1 -[3-(6-Methyl-pyridin-2-ylethynyl)-phenyl]-1 H-[1 ,2,4]triazoiε-3-carboxylic acid dimethylamidε 1-[3-(6-Mεthyl-2-phenylεthynyl-pyridin-3-yloxy)-propyl]-piperidin-4-ol 5-(6-Mεthyl-pyridin-2-ylεthynyl)-2-nitro-phenol 5-[2-Bromo-2-(6-methyl-pyridin-2-yl)-vinyl]-2-nitro-phenol 5-[2-(6-Methyl-pyridin-2-yl)-E-vinyl]-2-nitro-phenol 5-[2-(6-Methyl-pyridin-2-yl)-Z-vinyl]-2-nitro-phenol 4-Azido-2-hydroxy-N-[3-(6-methyl-pyridin-2-ylethynyl)-phenyl]-b8nzamide 5-(3-Dimethylamino-propoxy)-6-phenylethynyl-pyridine-2-carboxyiic acid ethyl ester 6-Methyl-2-styryl-pyrimidin-4-ol 2-Ethyl-6-(3-fluoro-phenylethynyl)-pyridine 2-(3,5-Dichloro-phenylethynyl)-6-methyl-pyridine 2-Methyl-6-(3-trifluoromethoxy-phenylεthynyl)-pyridinε 2-Methyl-6-(3-[1 ,2,4]triazol-1 -yl-phenylεthynyl)-pyridine 4-(6-Mεthyl-pyridin-2-yiεthynyl)-phthalonitrile 2-Methyl-6-{2-[3-(1H-t8trazol-5-yl)-phεnyl]-vinyl}-pyridine; compound with formic acid 3-[2-(3,5-Dichloro-phenylethynyl)-6-methyl-pyridin-3-yloxy]-propyiaminε {3-[2-(3,5-Dichloro-phenylεthynyl)-6-methyl-pyridin-3-yloxy]-propyl}-dimethyl-amine 2-(3,5-Dimethyl-phεnylethynyl)-3-methoxy-6-methyl-pyridine 2-[2-(3-Fluoro-phenyl)-vinyi]-6-methyl-pyridin-3-ol 6-(3-Fluoro-phenylethynyl)-2-methyl-nicotinic acid ethyl ester 2-Azido-5-(6-methyl-pyridin-2-ylethynyl)-phenol 6-(3,4-Dimethoxy-phenylethynyl)-5-(3-dimethyiamino-propoxy)-pyridiπe-2-carboxylic acid ethyl ester 2-(4-Methoxy-3-trifluoromethyl-phenyiethynyl)-6-methyl-pyridine 2-(3-Fluoro-phenylεthynyl)-6-mεthoxy-pyridine 2-(3-Fluoro-phenylεthynyl)-5-mεthyl-pyridine 6-(3,5-Dichloro-phenylethynyl)-5-(3-dimethylamino-propoxy)-pyridine-2-carboxylic acid εthyl ester 5-(3-Dimethylamino-propoxy)-6-(3,5-dimethyl-phenylethynyl)-pyridine-2-carboxylic acid εthyl ester 6-(3-Fluoro-phenylethynyl)-2-mεthyl-nicctinic acid [6-(3-Fluoro-phenylethynyl)-2-methyl-pyridin-3-yl]-mεthanol [4-(4-Fluoro-benzoyl)-piperidin-1-yl]-[6-(3-fluoro-phεnyiethynyl)-2-methyl-pyridin-3-yl]- methanone 2-(3-Fluoro-phenylεthynyl)-6-mεthyl-nicotinic acid εthyl ester 2-(3-Fluoro-phenylεthynyl)-4,6-dimεthyl-pyridine 6-(3-Fluoro-phenylεthynyl)-.N.-(5-methoxy-indan-2-ylmethyl)-2-methyl-nicotinamide {[6-(3-Fluoro-phεnylethynyl)-2-mεthyl-pyridine-3-carbonyl]-amino}-phenyl-acetic acid mεthyl ester 2- ethyl-6-(5-methyl-thiophen-2-ylethynyl)-pyridine 2-Methyl-6-(2,3,5-trimethyl-phenylethynyl)-pyridine 3-{2-[2-(3-Fluoro-phenyl)-vinyl]-6-methyl-pyridin-3-yloxy}-propan-1-ol [6-(3-Fluoro-phenylethynyl)-2-methyl-pyridiπ-3-ylmethyl]-dimethyl-aminε 2,2-Dimethyl-propionic acid 3-[2-(3-fluoro-phenylethynyl)-6-methyl-pyridin-3-yloxy]-propyl ester 2-Azido-4-iodo-5-(6-methyl-pyridin-2-ylethynyl)-phenol 6-Azido-2,4-diiodo-3-(6-methyl-pyridin-2-yl8thynyl)-phenol 4-Azido-2-hydroxy-5-iodo-.N.-[3-(6-mεthyl-pyridin-2-ylethynyl)-phεnyl]-benzamid8 Acetic acid 3-acetoxymεthyl-5-(6-methyl-pyridin-2-ylεthy.nyl)-benzyl εster (Benzyl-{[2-(3-fluoro-phenylεthynyl)-6-methyl-pyridin-3-yloxy]-ac8tyl}-amino)-acεtic acid ethyl ester 2-[2-(3-Fluoro-phenyl)-vinyl]-6-mεthyl-isonicotinic acid εthyl ester 3-[2-(3-Fluoro-phenylethynyl)-6-mεthyl-pyridin-3-yloxy]-propan-1-ol [3-Hydroxymethyl-5-(6-methyl-pyridin-2-ylethynyl)-phenyl]-mεthanol (3-{2-[2-(3,5-Dimethyl-phεnyl)-viπyl]-6-methyl-pyridin-3-yloxy}-propyl)-dimethyl-amine [4-(4-Fluoro-benzoyl)-pipεridin-1 -yl]-{6-[2-(3-fluoro-phenyl)-vinyl]-2-methyl-pyridin-3-yl}- mεthanone 2-[2-(3-Fluoro-phenyl)-vinyl]-6-methyl-isonicotinic acid {6-[2-(2-Chloro-phεnyl)-vinyl]-2-methyi-pyridin-3-yl}-[4-(4-fluoro-benzoyl)-pipεridin-1-yl]- mεthanonε 2-(3-Ethynyl-phεnylethynyl)-6-m8thyl-pyridine (3-{2-[2-(2,6-Dichloro-phεnyl)-vinyl]-6-methyl-pyridin-3-yloxy}-propyl)-dimethyl-amine (3-{2-[2-(2,3-Dichloro-phεnyl)-vinyl]-6-methyl-pyridin-3-yloxy}-propyl)-dimethyl-amine 4-[6-(3-Fluoro-phεnyl8thynyl)-2-methyl-pyridine-3-carbonyl]-pipεrazine-1 -carboxylic acid tert.-butyl ester [6-(3-Fluoro-phenylethynyl)-2-methyl-pyridin-3-yl]-piperazin-1-yl-methanone [4-(4-Azido-2-hydroxy-b8nzoyl)-piperazin-1-yl]-[6-(3-fluoro-phεnylethynyl)-2-methyi-pyridin-3- yl]-methanone (3-{2-[2-(2,4-Dichloro-phenyl)-vinyl]-6-methyi-pyridin-3-yloxy}-propyl)-dimethyi-amine 2-(3-Fluoro-phenylethynyl)-6-methyl-isonicotinic acid ethyl ester 2-(3-Fluoro-phenylethynyl)-6-methyl-isonicotinic acid .tεrt.-butyl ester 2-(3-Fluoro-phenylethynyl)-6-methyl-isonicotinic acid [2-(3-Fluoro-phenylethynyl)-6-methyl-pyridin-4-yl]-methanol [4-(4-Fluoro-benzoyl)-piperidin-1-y!]-[2-(3-fluoro-phεnyl8thynyl)-6-mεthyl-pyridin-4-yl]- methanone 3-Allyloxy-2-[2-(3,5-dichloro-phenyl)-vinyl]-6-methyl-pyridine [2-(3-Fluoro-phenylethynyl)-6-methyi-pyridin-4-yl]-morpholin-4-yl-mεthanonε Acεtic acid 3-(6-methyl-pyridin-2-ylethynyl)-benzyl ester [2-(3-Fluoro-phenylethynyl)-6-methyl-pyridin-4-ylmεthyl]-dimethyl-amine (3-{2-[2-(3,5-Dichloro-phenyl)-propenyl]-6-m8thyl-pyridin-3-yloxy}-propyl)-dimethyl-aminε 2-(3-Fluoro-phεnyl8thynyl)-3-methoxy-6-mεthyl-pyridinε (3-{2-[2-(3,5-Dichloro-phenyl)-vinyl]-pyridin-3-yloxy}-propyl)-dimethyl-amine (4-Azido-2-hydroxy-5-iodo-phenyl)-{4-[6-(3-fluoro-phεnylεthynyl)-2-mεthyl-pyridine-3- carbonyl]-piperazin-1 -yl}-mεthanone 4-Azido-N-{3-[2-(3-chloro-phεnylethynyl)-6-methyl-pyridin-3-yloxy]-propyi}-2-hydroxy-5-iodo- benzamide 4-(2-Pyridin-2-yl-vinyl)-benzoic acid ethyl ester (3-{2-[2-(4-Chloro-phenyl)-vinyl]-6-mεthyl-pyridin-3-yloxy}-propyl)-dimethyl-amine [3-(6-Methyl-pyridin-2-ylethynyl)-phεnyl]-mεthanol 6-(3-Fluoro-phenylethynyl)-nicotinic acid tεrt.-butyl εster (3-{2-[2-(3,4-Dich!oro-phenyl)-vinyl]-6-methyl-pyridin-3-yloxy}-propyl)-dimεthyl-amine 2-(1-Bromo-2-pheπyl-vinyl)-4-mεthyl-pyrimidinε 6-(3-Fluoro-phεnylethynyl)-nicotinic acid [4-(4-Fluoro-benzoyl)-pipεridin-1-yl]-[6-(3-fluoro-phenylethynyl)-pyridin-3-yl]-methanon8 2-(2-.tert.-Butoxy-3,6-difluoro-phenylεthynyl)-6-methyl-pyridine 2-Methyl-6-[2-(2,4,5-trifiuoro-phenyl)-vinyl]-pyridine 2-Methyl-6-[2-(2,3,4-thfluoro-phenyl)-vinyi]-pyridine 3-(6-Methyl-pyridin-2-ylethynyl)-phenol 2-Methyl-6-[2-(3,4 1 5-trifluoro-ph8nyl)-vinyl]-pyridinε 2-(3- εthoxy-phenylethynyl)-6-m8thyi-pyridinε 2-Methyl-6-(2,3,4-trifluoro-phεnylethynyl)-pyridine and pharmaceutically acceptable saits thereof. 10. (3-{2-[2-trans-(3,5-dichlorophenyl)-vinyl]-6-methyl-pyridin-3-yloxy}-propyl)- dimethylamine in free form or in form of a pharmaceutically acceptable salt. 11. A pharmaceutical composition comprising as pharmaceutical active ingredient, together with customary pharmaceutical excipients, a compound according to any of claims 6 to 10, in free form or in form of a pharmaceutically acceptable salt. 12. A method of treating disorders mediated full or in part by mGluRI or mGluRδ, which method comprises administering to a warm-blooded organism in need of such treatment a therapeutically effective amount of an 2-arylalkenyl- , 2-heteroarylalkenyl-, 2-arylalkynyl-, 2-heteroarylalkynyl-, 2-arylazo- and 2-heteroaryiazo- pyridine or a pharmaceutically acceptable salt thereof.

Inventors: ALLGEIER HANS, AUBERSON YVES, BIOLLAZ MICHEL, COSFORD NICHOLAS DAVID, GASPARINI FABRIZIO, HECKENDORN ROLAND, JOHNSON EDWIN CARL, KUHN RAINER, VARNEY MARK ANDREW, VELICELEBI GOENUEL, ALLGEIER, HANS, AUBERSON, YVES, BIOLLAZ, MICHEL, COSFORD, NICHOLAS, DAVID, GASPARINI, FABRIZIO, HECKENDORN, ROLAND, JOHNSON, EDWIN, CARL, KUHN, RAINER, VARNEY, MARK, ANDREW, VELICELEBI, GOENUEL
Applicants: ALLGEIER HANS, AUBERSON YVES, BIOLLAZ MICHEL, COSFORD NICHOLAS DAVID, GASPARINI FABRIZIO, HECKENDORN ROLAND, JOHNSON EDWIN CARL, KUHN RAINER, NOVARTIS AG, NOVARTIS ERFIND VERWALT GMBH, SIBIA NEUROSCIENCES INC, VARNEY MARK ANDREW, VELICELEBI GOENUEL, ALLGEIER, HANS, AUBERSON, YVES, BIOLLAZ, MICHEL, COSFORD, NICHOLAS, DAVID, GASPARINI, FABRIZIO, HECKENDORN, ROLAND, JOHNSON, EDWIN, CARL, KUHN, RAINER, NOVARTIS-ERFINDUNGEN VERWALTUNGSGESELLSCHAFT MBH, SIBIA NEUROSCIENCES INC., VARNEY, MARK, ANDREW, VELICELEBI, GOENUEL
Application year: 1998
Main classification: C07D213
IPC codes: A61K31, A61P9, A61P21, A61P25, A61P43, C07D213, C07D215, C07D401, C07D405, C07D409, C07D413, C07F7