Propane-1,3-diyl Dithioacetals of Carbohydrates; Part 7: Preparation of Aminocyclitols and Iminosugars by Intramolecular Cyclizations of d-Glucosamine Propane-1,3-diyl Dithioacetal Derivatives

Abstract

Versatile 3,4,5-tri-O-protected 2-acylamino-2-deoxy-6-O-tosyl-d-glucose propane-1,3-diyl dithioacetal intermediates were efficiently synthesized from d-glucosamine propane-1,3-diyl dithioacetal or its derivatives. Intramolecular cyclizations from these intermediates produced biologically important aminocyclitols as well as iminosugars. The 3,4-O-methylene protection on the intermediates did not hinder the cyclizations. The resultant aminocyclitols and iminosugars bearing orthogonal protecting groups are ideal for regioselective modification. Hence, deprotection methodology is also discussed.

Key words

chiral pool - intramolecular cyclizations - aminocyclitol - iminosugar - protecting-group cleavage

References

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