De Novo Asymmetric Synthesis of an α-6-Deoxyaltropyranoside as Well as its 2-/3-Deoxy and 2,3-Dideoxy Congeners
摘要:
A highly divergent de novo asymmetric synthesis of benzyl alpha-6-deoxyaltropyranoside, benzyl alpha-ascarylopyranoside, benzyl alpha-amicetopyranoside, and benzyl a-digitoxopyranoside has been achieved via I common pyranone intermediate. The routes rely upon it palladium(0)-catalyzed glycosylation reaction and corresponding post-glycosylation transformations, The control of the absolute and relative stereochemical configuration came from a Noyori reduction of 2-acylfuran and subsequent diastereoselective introduction of other stereogenic centers.