Synthesis of phospholipids via phosphotriester intermediates

New Phosphorylating Agents for the Synthesis of Phosphatidyl­ethanolamines

The preparation of three novel phosphorylating agents and their application toward the synthesis of phosphatidylethanolamines is described. These reagents are stable to air and moisture, and phosphorylate glycerols in good yield. The experimental procedures using these phosphorylating agents are simple. Moreover, the appropriate reagent can be selected based on the desired functional groups of the targeted phosphatidylethanolamine.

Synthesis of allyl 6-O-(3-deoxy-alpha- and -beta-D-manno-oct-2- ulopyranosylonic acid)-(1----6)-2-deoxy-2-[(3R)-3-hydroxytetradecanamido]- beta-D-glucopyranoside 4-phosphate and of the copolymer of the alpha anomer with acrylamide

The title disaccharides were synthesized by mercuric cyanide-catalyzed condensation of methyl (4,5,7,8-tetra-O-acetyl-3-deoxy-alpha-D-manno-oct-2-ulopyranosyl bromide)onate and allyl 2-[(3R)-3-acetoxy-tetradecanamido]-3-O-benzyl-2-deoxy-beta-D- glucopyranoside, followed by phosphorylation of the alcoholic function of the amino sugar. The phosphorylated anomers were separated by chromatography and deprotected by conventional methods. Polymeric material was obtained by copolymerisation, catalyzed by peroxosulphate and N,N,N',N'-tetramethylethylenediamine, of the alpha anomer with acrylamide; it contained ca. one disaccharide unit for 18 acrylamide residues.

Simple preparation of 1,2-dipalmitoyl-sn-glycero-3-phosphoric acid and deuterated choline derivatives

Analytically pure 1,2-dipalmitoyl-sn-glycero-3-phosphoric acid was prepared in gram amounts, using a simplified version of a previous procedure. The main step, enzymatic cleavage of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine with freshly extracted phospholipase D, was performed in the presence of chloroform and the crude phosphatidic acid was purified by silica gel column chromatography. The interest of the method was illustrated by the synthesis of two dipalmitoyl phosphatidylcholines selectively deuterated on the polar headgroup.

Synthesis of glycerophospholipids

Recent advances in the synthesis of phosphatidic acids, phosphatidylethanolamines and phosphatidylcholines are described. Methods for the synthesis of some alkylacyl and alk-1-enylacyl analogues of the common diacylglycerophospholipids are also discussed. In addition, synthetic routes are described, that lead to unusual phospholipids such as compounds containing the polar group at position 2 of the glycerol moiety, glycerophospholipids containing alkanolamines of different chain lengths, and glycolphospholipids. All of the common glycerophospholipids can be prepared without the use of protecting groups. Major advances in phospholipid synthesis involve the application of novel phosphorylating agents and the use of cyclic intermediates. Although phosphatidylserines and phosphatidylthreonines as well as phosphatidylglycerols and cardiolipins can be prepared by chemical synthesis, further systematic studies are required to work out procedures that lead to these compounds in high yields.