[EN] PROCESS AND ESTER DERIVATIVES FOR PREPARATION OF CEPHALOSPORINS<br/>[FR] PROCEDE ET DERIVES D'ESTER UTILES POUR LA PREPARATION DE CEPHALOSPORINES
申请人:PFIZER PROD INC
公开号:WO2002046199A1
公开(公告)日:2002-06-13
This invention relates a process for preparing a compound of formula (I) wherein R1 is para-nitrobenzyl or allyl; and X is halo, which is useful to prepare 3-cyclic-ether-substituted cephalosporins, from trimethylphosphinic compounds. This invention also relates to compounds useful in such process.