| 摘要 |
A process for the preparation of an antibacterially active compound of the formula (I): <CHEM> and salts and esters thereof wherein R<1> and R<2> independently represent hydrogen or an organic group, and R<3> is an optionally substituted aromatic or heteroaromatic moiety, which comprises reacting a compound of the formula (II): <CHEM> wherein R<a> is hydrogen or a carboxy-blocking group, with X-R<3> wherein X is a displaceable group, In addition certain compounds within the formula (II) are novel. |
