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ChemInform Abstract: Preparation of Ceph-3-em Esters Unaccompanied by δ3 → δ2 Isomerization of the Cephalosporin.
First published: June 16, 1987
Abstract
Direct alkylation of the 3-cephemcarboxylates (I) with the alkyl bromides (II) gives almost exclusively the 3-cephem esters (III), when a solvent mixture of DMF and dioxane is used.
ChemInform Abstract
Direct alkylation of the 3-cephemcarboxylates (I) with the alkyl bromides (II) gives almost exclusively the 3-cephem esters (III), when a solvent mixture of DMF and dioxane is used. In DMF alone, considerable isomerization to the corresponding 2-cephem esters takes place. (IR-, 1H-NMR-data).
