Direct Synthesis of Plasmenylcholine from Allyl-Substituted Glycerols
作者:Junhwa Shin、David H. Thompson
DOI:10.1021/jo026826w
日期:2003.8.1
We report a new method for the facile preparation of plasmenylcholine via reaction of lithioalkoxy allyl intermediates with 1-iodoalkanes as the key step in the stereoselective formation of 1'-(Z)-alkenyl glyceryl ethers. The allyl anion intermediate is prepared by treating mono- or disiloxyprotected 1-allylglycerol precursors with s-BuLi at -65 to -80degreesC. Subsequent addition of 1-iodoalkane solutions at low temperature gives moderate yields of gamma-coupled, Z-vinyl ethers as the major product and alpha-coupled product as the minor component. Several different preparative strategies for the total synthesis of plasmalogens are enabled by this simple transformation.
Improved Plasmalogen Synthesis Using Organobarium Intermediates
作者:Jeroen Van den Bossche、Junhwa Shin、David H. Thompson
DOI:10.1021/jo0705059
日期:2007.6.1
An improved synthesis of plasmalogen type lipids is described. Transmetalation of lithioalkoxy allyl intermediates with BaI2 and subsequent alkylation with 1-iodoalkanes enables the stereoselective formation of O-(Z)-alkenyl ether as precursors for the synthesis of plasmenyl- and bisplasmenylcholines. This method provides a simple and adaptable approach for the stereocontrolled synthesis of plasmenyl derivatives with variations at the sn-1, sn-2, and sn-3 positions of the glycerol backbone.
Facile Synthesis of Plasmalogens via Barbier-Type Reactions of Vinyl Dioxanes and Vinyl Dioxolanes with Alkyl Halides in LiDBB Solution
作者:Junhwa Shin、Oleg Gerasimov、David H. Thompson
DOI:10.1021/jo025640u
日期:2002.9.1
sn-2 acyl substituent that easily migrates during silica gel purification. We report two facile synthetic methods for the preparation of racemic plasmenylcholines via a tandem reductive vinyl dioxane/dioxolane ring opening and alkyliodide coupling process that proceeds in a single pot reaction. The key step in the formation of (Z)-vinyl ether precursors for the production of plasmenylcholines is accomplished