High-Yield Regioselective Thiation of Biologically Important Pyrimidinones, Dihydropyrimidinones and Their Ribo, 2′-Deoxyribo and 2′, 3′-Dideoxyribo Nucleosides

Abstract

Abstract Convenient and high-yield regioselective thiation procedures based on the use of the Lawesson reagent in different solvents, are described for conversion of the 2- and 4-keto, and 2, 4-diketo pyrimidines to the corresponding 2(4)-thio, and 2, 4-dithio, derivatives. This method is applicable to thiation of the 4-keto groups of 5, 6-dihydropyrimidinones and pyrimidine nucleosides. The mild reaction conditions employed are such that it is the method of choice for compounds with labile glycosidic bonds, such as 5, 6-dihydropyrimidine nucleosides and the 2′, 3′-dideoxynucleosides currently of interest as antiretroviral, including anti-HIV, agents.