Towards the total synthesis of calyculin C: preparation of the C(9)-C(25) spiroketal-dipropionate unit.
نویسندگان
چکیده
An asymmetric synthesis of the C(9)-C(25) spiroketal fragment of calyculin C is described. Key steps include two crotylation reactions using successively Brown's reagent and (Z)-crotyltrifluorosilane for the formation of the anti, anti, anti stereotetrad, ynone formation by a Pd-catalyzed coupling of a thiol ester with a terminal alkyne and a double intramolecular hetero-Michael addition for the stereoselective construction of the spiroketal framework.
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عنوان ژورنال:
- Organic & biomolecular chemistry
دوره 8 19 شماره
صفحات -
تاریخ انتشار 2010