CARB 45 |
| A new enantiospecific synthesis of Masamune's AB-fragment (1) for bryostatin 7 is reported from D-mannose. Key steps in the new route include a chelation-controlled Meerwein-Pondorf-Verley reduction on an A-ring ketone to set the O(7) stereocenter, and an alkylative union between an A-ring dithiane fragment and a B-ring pyran iodide to establish the C(9)-C(10) bond between the A- and B-ring segments. Since we have previously synthesized Masamune's C-ring phenylsulfone 2, our new route to 1 constitutes a new and enantiospecific formal total synthesis of bryostatin 7.
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General Posters
8:00 PM-10:00 PM, Tuesday, 12 September 2006 Moscone Center -- Hall D, Poster
Sci-Mix
Division of Carbohydrate Chemistry |
