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Synlett 2006(18): 2977-2980  
DOI: 10.1055/s-2006-948200
LETTER
© Georg Thieme Verlag Stuttgart · New York

The Synthesis of a Combretastatin A-4 Based Library and Discovery of New Cooperative ortho-Effects in Wittig Reactions Leading to (Z)-Stilbenes

David C. Harrowven*a, Ian L. Guya, Melanie Howellb, Graham Packhamb
a School of Chemistry, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
Fax: +44(23)80596805; e-Mail: dch2@soton.ac.uk;
b Cancer Research UK Clinical Centre, University of Southampton School of Medicine, Southampton, SO16 6YD, UK
e-Mail: G.K.Packham@soton.ac.uk;
Further Information

Publication History

Received 10 February 2006
Publication Date:
04 August 2006 (online)

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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

    References and Notes

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2

http://www.clinicaltrials.gov/ct/show/NCT00113438.

10

Supplementary 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.

11

All 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).