Amino acid derivatives, process for the preparation thereof and pharmaceutical composition comprising the same.

摘要

An amino acid derivative of the formula: in which R<1> is hydrogen, lower alkyl, halo(lower)alkyl or aryl R<2> is hydrogen, hydroxy or protected hydroxy, R<3> is hydrogen, R<4> is lower alkyl, amino(lower)alkyl, carboxy(lower)alkyl, aminocarboxy(lower)alkyl, protected amino(lower)alkyl or protected amino-carboxy(lower)alkyl, R<5> is hydrogen or lower alkyl, and R<2> and R<3> may combine to be oxo, and its pharmaceutical acceptable salt, having anti-tumor activity a process for preparation thereof and pharmaceutical compositions comprising the same.