UN PROCEDIMIENTO PARA PREPARAR DERIVADOS DE PIRIDINA

摘要

The present invention provides compounds of formula (1):- …… and their pharmaceutically acceptable salts which are useful as histamine H1-antagonists. In formula (1)… R<1> is halogen, nitro, amino (or a pharmaceutically acceptable derivative of the amino group which is convertible in vivo into amino) or C1-4 alkyl;… R<2> is halogen, nitro, amino (or a pharmaceutically acceptable derivative of the amino group which is convertible in vivo into amino), C1-4 alkyl or C3-4 alkoxy;… R<3> is a C1-3 alkylene group; and… R<4> is a group of formula (2):- …… where R<5> is NCN, NNO2, NH or CHNO2 and R<6> is hydroxy, amino, C1-6 alkyl, optionally substituted phenyl- or pyridyl(C1-6)alkyl (the optional substituents being one or more C1-6 alkyl, or C1-6 alkoxy groups or halogen atoms or a methylenedioxy group);… or C2-4 alkynyl;… or R<4> is a group of formula (3):- …… where R<7> is a covalent bond or methylene or ethane-1, 2-diyl optionally substituted with one C1-6 alkyl group and a second C1-6 alkyl group or a phenyl(C1-6)alkyl group;… or a group of formula (4):- …… where R<8> is hydrogen; C1-6 alkyl; optionally substituted phenyl or phenyl(C1-6)alkyl, (the substituents being one or more C1-6 alkyl or C1-6 alkoxy groups or halogen atoms or a methylenedioxo group) or optionally substituted pyridyl or pyridyl(C1-6)alkyl, the optional substituents being one or more C1-6 alkyl groups or C1-6 alkoxy groups or halogen atoms; and R<9> is hydrogen or C1-6 alkyl;… or a group of formula (5):- …… where n is 0, 1 or 2… R<1><0> is hydrogen, C1-6 alkyl, or optionally substituted phenyl or phenyl(C1-6)alkyl (the substituents being one or more C1-6 alkyl, or C1-6 alkoxy groups or halogen atoms); or a methylenedioxy group or optionally substituted pyridyl or pyridyl(C1-6)alkyl where the optional substituents are one or more C1-6 alkyl or C1-6 alkoxy groups or halogen atoms;… or a group of formula (6):- …… where R<1><1> is hydrogen, C1-6 alkyl, optionally substituted phenyl or phenyl(C1-6)alkyl, (the substituents being one or more C1-6 alkyl or C1-6 alkoxy groups or halogen atoms or a methylenedioxy group); optionally substituted pyridyl or pyridyl(C1-6)alkyl, the optional substituents being one or more C1-6 alkyl groups or C1-6 alkoxy groups or halogen atoms;… or a group of formula (7):- …… where R<1><2> is hydrogen or C1-6 alkyl, R<1><5> is hydrogen or together with R<1><2> is a fused benzene ring and m is 0, 1 or 2 or a group of formula (8):- …… where R<1><2> is hydrogen or C1-6 alkyl.