FREMGANGSMAATE FOR FREMSTILLING AV CEFEM-KARBOKSYLSYRE-ESTERE
摘要
<p>A compound represented by the formula (II) epimerizes by the action of a base and the product is precipitated for shifting the equilibrium to yield the corresponding epimer represented by the formula (I). <IMAGE> (II) <IMAGE> (I) wherein Ar is an optionally substituted aryl or heterocyclic group; Tet is an optionally substituted tetrazolyl group and B1 and B2 are each ester forming group in the field of penicillin or cephalosporin chemistry.</p>
