Peptide derivatives

摘要

PCT No. PCT/JP94/01560 Sec. 371 Date Apr. 1, 1996 Sec. 102(e) Date Apr. 1, 1996 PCT Filed Sep. 22, 1994 PCT Pub. No. WO95/09864 PCT Pub. Date Apr. 13, 1995A peptide derivative represented by the following formula or a salt thereof +TR wherein A and B each represent either of the following (a) and (b), (a) A represents a hydrogen atom, and B represents a phenyl group substituted with a halogen atom, hydroxyl group, lower alkyl group or lower alkoxy group, or a heteroaryl group, (b) A represents -CONH-R1, -CSNH-R1, a hydroxymethyl group, a lower alkoxycarbonyl group or a carboxyl group, wherein, R1 represents a lower alkyl group or a heteroaryl group, and B represents a phenyl group optionally substituted with a halogen atom, hydroxyl group, lower alkyl group or lower alkoxy group, has an antitumor activity stronger than that of dolastatin 10, and is useful as an anticancer or antitumor agent.