| 摘要 |
NEW MATERIAL:A compound expressed by formula I [n is 0, 1 or 2; R is phenyl substituted by halogen or alkoxy, (CH2)m-OR2 (m is integer of 1-6; R2 is protecting group commonly used in penicillin derivative); R1 is R2] and salt thereof. EXAMPLE:2beta-(1-p-Chlorophenyl-5-tetrazolylthio)methyl-2alpha-methylp enam-3alpha-carbo xylic acid p-nitrobenzyl ester. USE:A beta-lactamase inhibitor capable of improving an antimicrobial activity of beta-lactam based antibiotic in use together with said antibiotic. PREPARATION:A penicillin derivative expressed by formula II (X is Cl or Br; R<1> is penicillincarboxyl-protecting group) is reacted with a mercaptotetrazole derivative to provide a compound expressed by formula IV, which is oxidized with an oxidant such as peracetic acid, etc., to afford a dioxide expressed by formula V via a sulfoxide intermediate, followed by deesterification. |
