| 摘要 |
<p>The invention relates to a novel process for preparing cephalosporins of the formula <IMAGE> in which R2 is hydrogen, cation, pivaloyloxymethyl or carboxyl and R3 is hydrogen, acetoxy, carbamoyloxy or S-Y, in which Y denotes an optionally substituted heterocyclic group or, where appropriate, a substituted pyridinium group, by removing the protecting group from a compound of the formula <IMAGE> by treating the latter with an aliphatic alcohol under acid conditions.</p> |
