ORGN 676 |
| The enantioselective syntheses of naturally occurring kaempferol glycoside SL0101 and its analogues, as well as their enantiomers, have been achieved in 7-10 steps. The routes rely upon a diastereoselective palladium-catalysed glycosylation, ketone reduction, and dihydroxylation to introduce the rhamno-stereochemistry. The asymmetry of the sugar moiety of these kaempferol glycosides was derived from Noyori reduction of a furanketone. An acetyl group shift from an axial (C-2) to equatorial position (C-3) under basic conditions was also described. |
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Heterocycles and Aromatics, Asymmetric Reactions and Syntheses and Total Synthesis of Complex Molecules
7:00 PM-9:00 PM, Wednesday, August 19, 2009 Walter E. Washington Convention Center -- Ballroom C, Poster
Division of Organic Chemistry |