| 摘要 |
<p>A compound of formula I <IMAGE> (I) with R1 being an alkyl group substituted by one or more substituents and esters thereof at the 2-carboxy group or at the 8-hydroxy group or both; and salts thereof. Compounds I have antibacterial effect. Various intermediates are described. This compound of the formula I, or an ester at the 2-carboxy group or at the 8-hydroxy group or both or a salt thereof is produced by reacting a compound of formula II or of formula IX <IMAGE> II <IMAGE> IX in which R represents a hydrogen atom or a carboxy protecting group, R3 represents an activated carboxylic acid group, R4 represents an alkyl group having 1 to 4 carbon atoms, or a phenyl group which may be unsubstituted or substituted, R15 represents a phenyl group or an alkyl group having from 1 to 4 carbon atoms, and X represents an oxygen or sulphur with an amine of the formula III R1NH2 (III) to give a compound of formula I, or an ester thereof of formula Ia <IMAGE> (Ia)</p> |
