Abstract
(R )-[(2-Oxo-4-thiazolidinyl)methyl]triphenylphosphonium
iodide (1 ), readily prepared in five steps
from l -cysteine ethyl ester (39% overall
on a 500 g scale), is a useful Wittig reagent for the synthesis
of cysteine-derived alkenes such as those found in dipeptide isosteres
and peptidomimetics. Preparation of 1 and
its use in Wittig olefination reactions with aldehydes is described.
The resulting thiazolidinone compounds are readily unmasked to provide
the corresponding thiol, symmetrical disulfide, or S -trityl
derivatives.
Key words
Wittig reaction - aldehydes - alkenes - peptidomimetics - thiazolidinones
References 1 Current address: School of Pharmacy,
JiangSu University, Zhenjiang City, Jiang Su Province, ZP 212003,
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; Chem. Abstr. 2003 , 138, 4818
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[¹
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