Pyridonecarboxylic Acids as Antibacterial Agents. VIII. An Alternative Synthesis of Enoxacin via Fluoronicotinic Acid Derivatives

Abstract

An alternative synthesis of enoxacin, a 1, 8-naphthyridine antibacterial agent, was developed. The present method involves 1, 8-naphthyridine ring construction by the Dieckmann type cyclization of ethyl 5-fluoronicotinate having a 2-ethoxycarbonylethylamino moiety at C-2. This nicotinate was prepared in 7 steps from ethyl fluoroacetate via ethyl 2, 6-dichloro-5-fluoronicotinate.