| Phospholipids analogous are the main components of biological membranes. A characteristic of phospholipids is the amphiphilic behavior, depending on which, stable bilayer structure can be freely formed by itself making a vesicle of lipid bilayer. With this character, a novel drug preparation technology has developed as liposome, with such merits as targeting, duration etc. The usage of natural phospholipids was limited for the disadvantages of short life, frangibility to oxidation and less stableness. The problem can be solved by synthetic phospholipids, broadened the studying and application section of liposomes. Additionaly, synthetic phospholipids can be used for such advanced drug delivery technologies as fat emulsion, microemulsion, and so on. The total synthetic scheme of glycerol phospholipids was designed with the precursor glycerol. Ketal, 3,4-dimethoxybenzyl were adopted as the protecting groups of glycerol skeleton and aqueous acetic acid and 2,3-dichloro-5,6- dicyanoquinone (DDQ) as the deprotecting reagents respectively. Methyl p-toluenesulfonate, tert-butoxycarbonyl, was adopted as the protecting groups of N,N-dimethyl -ethanolamine and ethanolamine respectively, and aqueous NaHCO3, trifluoroacetic acid as the deprotecting reagents respectively. Extraction, high vacuum distillation, and liquid column chromatography etc., were adopted as the separating methods. After reduction, substitution, chlorination, condensation, protection and deprotection, acylation, and the connection of the head groups, distearoyl phosphatidylcholine (yield:42%) ,distearoyl phosphatidylglycerol (yield:41%) and distearoyl phospha -tidylethanolamine(yield:26%) were obtained. Some 14-C and 16-C intermediates have been synthesized. The products and some intermediates was characterized by IR and NMR.The separations of some steps were simplified. The feasibility of the lipid synthetic scheme has been proved. And basic work has been done for the mass manufacture of the phospholipids.
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