A new stereoselective route to branched-chain nitro and amino sugars: synthesis of both enantiomers of decilonitrose and avidinosamine
作者:Ralph Greven、Peter Juetten、Hans Dieter Scharf
DOI:10.1021/jo00066a029
日期:1993.7
Short, efficient, and highly diastereoselective syntheses of the title carbohydrates (15, 21, and 22), components of new anthracycline antibiotics, on a gram scale from readily available keto sugar precursors 6 and 17 are described. The syntheses feature the smooth and clean addition of organocerium compounds to benzyloxyimino derivatives 7 and 18, which provide the branched-chain hydroxyamino sugars (9,20) bearing an equatorial methyl group with complete regio- and stereocontrol. Treatment of oximino deoxy sugars (7,18) with methyllithium resulted in beta-elimination and afforded pyranoid 1-enol 3-one oximes (8, 19).