Synthesis of Deuterium-Labeled Plant Sterols and Analysis of Their Side-Chain Mobility by Solid State Deuterium NMR.

The plant sterols sitosterol and stigmasterol exert very different effects on plant model membranes, the first one being a "reinforcer" like cholesterol, the second one not. 25-(2)H-Stigmasterol has been synthesized by coupling of the 22-aldehyde derived from stigmasterol by ozonolysis, with the proper sulfone labeled in position 25. The configuration of the ethyl side chain at C-24 was controlled by separation of the diastereomers introduced via a chiral sulfoxide.