Synthetic approaches to thiathromboxanes. Part 2. Synthesis of structural isomers of thiathromboxane A2

Structural isomers (15) of monothiathromboxane A2 have been prepared from the half-ester (1). The basic strategy involved introduction of the ‘bottom’ side-chain by Michael addition, lactonisation, removal of ethoxycarbonyl, and conventional introduction of the ‘top’ side-chain. A link with a published dithiathromboxane synthesis is described.