Synthese der Kephaline

Abstract

Aus d. Hauptlaborat. d. Firma Georg S c h i c h t A,-G., AuBig a. d. I$,!Nachdem es uns gelungen war, Cholin-Lecithine oder Lecithine im engeren Sinne des Wortes zu synthetisieren, versuchten wir selbstverstandlich, die Methode auf die Darstellung der A m i n o -a t h a n o l -L e c i t h i n e oder K e p h a -line1) zu iibertragen. Diese Verbindungen sind weniger bekannt als die Cholin-Lecithine, ihre Erforschung hat ja auch vie1 spater begonnen, sie wurde eigentlich erst 1911 durch T r i e r auf eine sichere Basis gestelltz).

Historical perspective: phosphatidylserine and phosphatidylethanolamine from the 1800s to the present

“…PE was first purified more than one hundred years ago (1913) from cattle brain by Renall (19), who discovered that the two acyl chains of PE were typically different from one another, as was also the case for lecithin. As confirmation of the structural makeup of PE, the complete chemical synthesis of distearoyl-PE was achieved in 1924 by Levene and Rolf (20), and also by Grun and Limpacher (21). Subsequently, cephalin was chromatographically separated into two phosphoglycerolipids, PS and PE, by Folch (22).…”

The Structure of the Phospholipids.

“…Mathews (40, page 592) quoted Mac-Arthur as finding aminooxybutyric acid and serine, but did not give the basis for the conclusion or a specific reference. Syntheses by Grün and Limpácher (20) and by Kabashima (22,23), using aminoethanol, gave products sufficiently similar to natural cephalin to be considered by them as identical, and Rudy and Page (46) obtained, by special preparation from natural cephalin, a product which doubtless had only aminoethanol as its base. With cephalin the divergence of the elementary analysis from that calculated for the accepted formula has been much greater than has been the case with lecithin.…”

The Chemistry of the Lipins

“…Two explanations of this discrepancy have been put forward: (a) that some oxidation of the highly unsaturated acids always occurs; and (b) that the kephalin had not been completely freed from the degradation products, which are more easily split off than in the case of lecithin. The synthesis of distearyl kephalin by Griin and Limpacher (16) suggested useful improvements in the isolation of the natural product which have proved fruitful in the hands of Rudy and Page (17). The marked differences in the properties of synthetic lecithin and kephalin are probably related to the presence in lecithin of the str'ong base choline and its substitution in kephalin by the weak base amino ethyl alcohol.…”