An efficient reduction of azide to amine: a new methodology to synthesize ethyl 7-amino-1-ethyl-6,8-difluoroquinolone-3- carboxylate and its spectroscopic characterization

Abstract

Most of the quinolone antibacterial research has been focused on the functionality at C-7 position where the nature of substituents is responsible for antibacterial spectrum, potency, bioavailability, and side effects of the quinolones. Then, a 7-amino-fluoroquinolone could be the starting point of a wide variety of potentially useful compounds like tetracyclic and tricyclic quinolones or secondary amines with side chain derivatives. This attracted our attention to synthesize a 7-azide-fluoroquinolone, which could be converted to amine performing a photochemical reaction using CuI as catalyst. FT-IR and H1 NMR spectra of the final product, ethyl 7-amino-1-ethyl6,8-difluoroquinolone-3-carboxylate, suggests the formation of dimers, a feature already observed in norfloxacin.