Two Straightforward Strategies for the Synthesis of Thiodisaccharides with a

REPETTO, EVANGELINA; MARINO, CARLA; UHRIG, MARÍA LAURA; VARELA, OSCAR

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY

Año: 2008 vol. 2008 p. 540 - 547

1434-193X

Thiodisaccharides having a 1-thiopentofuranose nonreducing end were synthesized by two routes starting from per-Oacylaldofuranoses with arabino, ribo, and xylo configurations. These glycosyl donors were converted into S-glycosyl isothiourea derivatives as precursors of 1-thiofuranose units, which were generated in situ and trapped by a sugar enone to produce, by Michael addition, the thioglycosidic linkage. Alternatively, the MoO2Cl2-promoted glycosylation of the thiol group of 6-thiosugar derivatives by per-O-acylfuranose led to thiodisaccharides with exclusive 1,2-trans diastereocontrol.