Glycerylphosphorylcholine and choline glycerophosphate.

In 1938-9 at the British Postgraduate Medical School, King & Aloisi isolated from dried pancreas a glycerophosphoric ester of choline which was found to be readily hydrolyzable. Evidence was also obtained for the existence of a dicholine ester. This work was published only in 1945 owing to war difficulties. In the same year Schmidt, Hershman & Thanmhauser (1945) reported the isolation of aglycerylphosphorylcholine from the same material. They also found that the ester was very rapidly split by N-hydrochloric acid. We have now tried to synthesize the choline esters of both aand f-glycerophosphoric acid in order to examine their metabolic behaviour in animal tissues and other cells. The products obtained by the few methods recorded in the literature for the synthesis of ,-glycerylphosphorylcholine (Arnold, 1940; Ravazzoni & Fenaroli, 1940; Belfanti, Ercoli & Francioli, 1940; Mihalik, Jeney & Uri, 1941) seemed unlikely to us to be esters of choline (1), but rather to be salts of choline and pglycerophosphoric acid (i.e. fi-glycerophosphate of choline) (2).