1,4-DIHYDROPYRIDINE DERIVATIVES

摘要

A 1,4-dihydropyridine derivative having the formula (I): <CHEM> wherein, R1 represents a substituted or unsubstituted phenyl or pyridyl group, R2 represents a C1 to C5 lower alkyl group, R3 represents a substituted or unsubstituted C1 to C8 alkyl, alkenyl, alkynyl or substituted or unsubstituted C3 to C7 cycloalkyl or cycloalkenyl group, R4 represents -A-R5, wherein A represents a C3 to C5 alkynylene group having one triple bond, and R5 represents a substituted or unsubstituted pyridyl, quinolyl, isoquinolyl or pyrimidyl group and a drug for overcoming resistance to an anti-cancer drug or a drug increasing the effect of an anti-cancer drug containing as an effective ingredient the derivative or its pharmacologically acceptable salt or hydrate.