Studies on β-Lactam Antibiotics. IV. Synthesis of Apalcillin

Abstract

Apalcillin sodium is a novel semisynthetic penicillin derivative that possesses a broad spectrum of in vitro and in vivo antibacterial activities. Apalcillin sodium (I) and its L-isomer were prepared by reacting D (-)-α-aminobenzylpenicillin or its analogs with the appropriate acylating derivatives of 4-hydroxy-1, 5-naphthyridine-3-carboxylic acid (II). Treatment of the crude I with dimethyl sulfoxide gave the highly-purified dimethyl sulfoxide adduct (I·DMSO), which was converted to the highly-purified I. L-Isomer was active against S. aureus, but not against E. coli, K. pneumoniae, P. mirabilis, and P. aeruginosa.