Documentation scienceplus.abes.fr version Bêta

À propos de : Total Synthesis of the Annonaceous Acetogenin (+)-Asimicin.Development of a New Bidirectional Strategy        

AttributsValeurs
type
Is Part Of
Subject
Title
  • Total Synthesis of the Annonaceous Acetogenin (+)-Asimicin.Development of a New Bidirectional Strategy
has manifestation of work
related by
Author
Abstract
  • The total synthesis of the Annonaceous acetogenin (+)-asimicinis described. The approach employsthe (R)-α-OSEM allylic stannane 7 of >95% eeand the dialdehyde 8 obtained from(S,S)-diethyltartrate. Addition of 7 to 8 in the presenceof InCl3 afforded the bis-adduct 9 in 71%yield.Tosylation and treatment with TBAF led to the corebis-tetrahydrofuran intermediate, diol 11, in78% yield. Mono tosylation (n-BuLi, TsCl, THF−DMSO)and subsequent hydrogenolysis withLiBEt3H gave alcohol 14. The iodide15 was coupled with the higher-order vinylcyanocupratetoafford olefin 30. This was converted to diol31 of high ee by the Sharpless protocol. Thisdiolyielded the epoxide 33 via the mono-trisylate 32.Addition of (R)-lithio-2-(OTBS)-3-butyne inthepresence of BF3·OEt2 afforded the alcohol34. The SEM derivative 35 was treated withTBAF,and the resulting alcohol was converted to the butenolide 38by a sequence involving treatmentwith (CF3CO)2O, thenPd(PPh3)4, CO, THF−H2O, andfinally AgNO3/silica gel. Cleavage of theSEM protecting group with PPTS in ethanol afforded (+)-asimicin(39).
article type
is part of this journal



Alternative Linked Data Documents: ODE     Content Formats:       RDF       ODATA       Microdata