N-(alkoxy-thiocarbonyl alpha-phenylglycol)6-amino-penicillinates - intermediates for ampicillin prepd. from penicillin G derivs

摘要

Penicillin G derivs of formula (I) are novel cpds. (where R1 = H or a protecting gp. and R2 = Y3-nCHn-CHR-Y = halo, = 0-2 and R = H or phenyl. Suitable protecting groups, R1, include benzyl, p-nitrobenzyl, 2,2,2-trichloroethyl, trityl, trimethylsilyl, phenacyl and p-bromophenacyl. (I) are intermediates for the prepn. of ampicillin by elimination of the protecting groups R2O-CS-, and R1.R2O-CS- may be eliminated by zinc or a zinc alloy and acetic acid and R1 by hydrogenolysis, acidolysis etc.