Method to build 2,4-substituted selenazole from beta-azido diselenide and carboxylic acid: A formal synthesis of selenazofurin

A novel approach for the synthesis of 2,4-disubstituted selenazoles using carboxylic acids (or anhydrides) and beta-azido diselenide was achieved via a one-pot cascade formation of selenazoline (Staudinger reduction/diselenide cleavage/selenocarbonylation/aza-Wittig reaction) and a following MnO2-promoted oxidation. This method offers excellent substrate flexibility, and its valuable application is exemplified by an efficient total synthesis of Selenazofurin which exhibited good antitumor activities against K562 and A549 cells. (C) 2018 Elsevier Ltd. All rights reserved.