Synthesis, in vitro and in vivo antifungal activity of 5-phenylthio-2,4-bisbenzyloxypyrimidine: a novel nucleobase.

A pyrimidne nucleobase, 5-phenylthio-2,4-bisbenzyloxypyrimidine and its analogs were synthesized and scanned for in vitro antifungal activity using cup-plate and macrobroth dilution method against Candida albicans, Aspergillus niger, Aspergillus flavus and Aspergllus fumigatus. In the cup-plate method, 5-phenylthio-2,4-bisbenzyloxypyrimidine showed very good antifungal activity compared to clotrimazole at the concentrations of 100 and 1000 μg/ml and in the macrobroth dilution method, it showed comparable activity with respect to standard drugs fluconazole and itraconaole. In vivo antifungal activity of 5-phenylthio-2,4-bisbenzyloxypyrimidine at the dose levels of 10 and 30 mg/kg was carried by causing systemic infection of mice using the same fungi used in in vitro testing. The results from in vivo studies with 5-phenylthio-2,4-bisbenzyloxypyrimidine and fluconazole indicated that 5-phenylthio-2,4-bisbenzyloxypyrimidine had similar potency as fluconazole at both dose levels.