The replacement of the ring oxygen of a pyranose or furanose system by sulfur[1] leads to sugar analogues, commonly called thiasugars,[2] which often exhibit interesting biological activities. Whereas numerous different synthetic routes to 5-thiopyranoses are well established,[3] easy and flexible approaches to 4-thiofuranose systems are still needed because such compounds could be used as sugar mimics, for instance, in nucleoside analogues. ...
