| 摘要 |
A compound of the formula I <IMAGE> (I) in which R1 represents a hydrogen atom or an alkyl group having from 1 to 4 carbon atoms, the -CONHR1 group being present at the 3- or 4-position on the phenyl ring, and esters thereof at the 2-carboxyl group and/or at the 8-hydroxy group, have antibacterial and/or beta -lactamase inhibiting activity. |
