The Sterols of Ergot. Ii. The Occurrence of Dihydro-Ergosterol

Abstract

Recently2 we briefly described the preliminary fractionation of "ergosterol" from ergot fat. Crude ergosterol was prepared from an ether solution of the unsaponifiable fraction by precipitation with petroleum ether. We have now studied this ether-petroleum ether filtrate. Originally our expectation was that fungisterol might be found there in such proportion that its isolation would be somewhat more readily accomplished. In this study we have incidentally isolated pure a-dihydro-ergosterol, which was first described by Windaus and Brunken.3 They report a specific rotation of -19.3°, and a melting point of 173-174°. The acetate melts at 180-181°and for [a]D they found -21.0°Heilbron, Johnstone and Spring4 report that the melting point of a-dihydro-ergosterol acetate varies from 179-180 to 173°, depending upon the duration of the acetylation process. The rotation, [a]!461, varied from -25.3 to -30.3°.1 Holder of the Upjohn Cooperative Fellowship at Kalamazoo College (1929)(1930). This paper is based upon the thesis presented by Mr. Swoap to the Faculty of Kalamazoo College, in partial fulfilment of the requirements for the degree of Master of Science.