A new synthesis of 7H-pyrido(1,2,3-de)(1,4)benzoxazine derivatives including an antibacterial agent, ofloxacin.

Abstract

A new method for the synthesis of 7H-pyrido[1,2,3-de][1,4]benzoxazine derivatives was developed. The method is characterized by the intramolecular cyclization of 1-(1-hydroxyprop-2-yl)-8-fluoro-4-quinolones which are prepared in three or four steps from ethyl 2,3,4,5-tetrafluorobenzoylacetate. As an application of this method, ofloxacin, an antibacterial agent, was synthesized.