Synthesis, photophysical property study of novel fluorescent 4-(1,3-benzoxazol-2-yl)-2-phenylnaphtho[1,2-d][1,3]oxazole derivatives and their antimicrobial activity

Abstract

A series of 4-(1,3-benzoxazol-2-yl)-2-phenylnaphtho[1,2-d][1,3]oxazole derivatives have been synthesized from intermediate 1-amino-3-(1,3-benzoxazol-2- yl)naphthalen-2-ol. This intermediate was obtained by coupling 3-(1,3-benzoxazol-2-yl)naphthalen-2-ol with 4-sulphobenzenediazonium chloride followed by reduction with sodium dithionate in water at pH 8-9. 3-(1,3-benzoxazol-2-yl)naphthalen-2-ol was synthesized from 3- hydroxynaphthalene-2-carboxylic acid and 2-amino phenol in the presence of PCl3 in chlorobenzene at 130-135 C. All these compounds were characterized by FT-IR, 1H NMR, mass spectral and elemental analysis. The synthesized compounds are fluorescent which absorbs in the range of 296 to 332 nm while emits in the ranges of 368 to 404 nm with excellent quantum yield. All compounds were evaluated for in vitro antibacterial activities against Escherichia coli and Staphylococcus aureus strains and in vitro antifungal activity against Candida albicans and Aspergillus niger strains by using serial dilution method. © 2013 Indian Academy of Sciences.