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DOI: 10.1055/s-2006-948200
The Synthesis of a Combretastatin A-4 Based Library and Discovery of New Cooperative ortho-Effects in Wittig Reactions Leading to (Z)-Stilbenes
Publication History
Publication Date:
04 August 2006 (online)
Abstract
A synthesis of combretastatin A-4 and a small library of analogues led to the discovery of some new cooperative ortho-effects allowing (Z)-stilbenes to be prepared in high yield and diastereomeric ratio.
Key words
alkenes - antitumor agents - stereoselective synthesis - total synthesis - Wittig reactions
- 1 Combretastatin A-4 was isolated from the bark of the African bush willow, Combretum caffrum. See:
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References and Notes
http://www.clinicaltrials.gov/ct/show/NCT00113438.
10Supplementary information providing characterization data for each of the (Z)-stilbenes reported herein, together with details of their preparation and the method of purification employed, is available from the author.
11All spectral and physical data were in close agreement with literature values, [1] [3] except for the mp, (lit. [1] 116 °C). Following recrystallization of our synthetic sample from either EtOAc or EtOAc-hexane, it gave mp 83-84 °C (recorded in duplicate on two separate apparatuses).