Dihydropyridine derivatives useful in antitumor therapy

摘要

Compounds which are useful in anti-tumors therapy having the formula (I) <IMAGE> (I) wherein Het imidazole, A represents a direct linkage at the phenyl 4-position: R is hydrogen; one of R3 and R4 is C1-C3 alkyl unsubstituted or omega substituted by C1-C3 alkoxy, and the other, independently, is: a) C1-C3 alkyl unsubstituted or omega substituted by C1-C3 alkoxy; or b) -(CH2)m-O-(CH2)n-NRaRb wherein each of m and n, which may be the same or different is an integer of 1 to 3, each of Ra and Rb, which may be the same or different, is hydrogen or C1-C3 alkyl; R5 is hydrogen or C1-C6 alkyl unsubstituted or substituted by a morpholino; each of R1 and R2 is independently a group -OR' wherein R' is C1-C6 alkyl; or a pharmaceutically acceptable salt thereof.