The paper describes an asymmetric convergent synthesis of 2-epi-saponaceolide B, illustrating a general approach to the construction of the saponaceolide structure. The strategic C10'-C11' bond was formed by coupling a lithium salt containing the left part of the molecule with a carbonyl derivative representing the right part. (C) 1999 Elsevier Science Ltd. All rights reserved.
Enantioselective synthesis of γ-cyclohomocitral, pallescensone, and ancistrodial
A simple and efficient enantioselective synthesis of γ-cyclohomocitral, a key and versatile intermediate for the synthesis of some monocyclofarnesane terpenoids, is described. This features a highly sitoselective Sharpless asymmetric didydroxylation of a homomonoterpene diolefin. The first enantioselective synthesis of (−)-ancistrodial and (−)-pallescensone were accomplished. The (S)- configuration