Thiosugars II. A novel approach to thiodisaccharides The synthesis of 3-deoxy-4-thiocellobiose from levoglucosenone

An expeditious methodology for the synthesis of β-(1 → 4)-3-deoxythiodisaccharides (3-deoxythiocellobiose) has been developed. The methodology is based on the stereoselective Michael addition of 2,3,4,6-tetra-O-acetyl-1-thio-β-d-glucose to levoglucosenone, followed by stereoselective reduction at C-2 with l-Selectride® and DIBAH, followed by acetolysis to the target thiodisaccharide derivative.