摘要 |
A peptide compound of the formula : <CHEM> wherein R<1> is aryl which may have one or more suitable substituent(s), R<2> is carboxy(lower)alkyl or protected carboxy(lower)alkyl, R<3> is carboxy or protected carboxy, A<1> is alkylene which may have one or more suitable substituent(s), A<2> is a group of the formula : <CHEM> (wherein R<4> is lower alkyl), or a group of the formula : -NHCH2CH2CO- , A<3> is lower alkylene which may have one or more suitable substituent(s), l , m and n are each the same or different an integer of 0 or 1, with proviso that A<2> is not a group of the formula : -NHCH2CH2CO- , when l is an integer of 0, or a pharmaceutically acceptable salt thereof, processes for their preparation and pharmaceutical compositions comprising them. |