ChemInform Abstract: New Route for the Synthesis of 2-Thiouracil Analogues of 3′-Azido-2′,3′ -dideoxy Nucleosides

Reaction of 3-azido-5-O-tert-butyldiphenylsilyl-2,3-dideoxy-D-erythro-pentofuranoside (5) with silylated 2-thiouracil and 5-alkoxy-2-thiouracils in the presence of trimethylsilyl trifluoromethanesulfonate afforded an anomeric mixture of the corresponding 3′-azido-2′,3′-dideoxy-2-thiouridine derivatives with the α-anomer as the main product. Deprotected nucleosides were obtained by treatment with tetrabutylammonium fluoride.