专利检索 ap:"Roy T. Sourander" 第 1 页

1.

发明授权
Method of controlling the epimeric distribution in the preparation of 16,17-acetals of pregnane derivatives 失效
标题翻译：在孕烷衍生物的16,17-缩醛的制备中控制差向异构体分布的方法

公开(公告)号：US4925933A

公开(公告)日：1990-05-15

申请号：US96598

申请日：1987-09-11

申请人： Edib Jakupovic , Roy T. Sourander , Jan U. Stenhede , Rolf P. Svensson

发明人： Edib Jakupovic , Roy T. Sourander , Jan U. Stenhede , Rolf P. Svensson

IPC分类号： C07J71/00

CPC分类号： C07J71/0031

摘要： A method of controlling the epimeric distribution in the preparation of 16,17-acetals of pregnane derivatives characterized in reaction of a corresponding 16,17-acetonide with an aldehyde or ketone in (a) hydrocarbon solvent wherein the solubility of the pregnane derivative is less than 1 mg/l or in a halogenated hydrocarbon solvent together with a hydrohalogen acid or an organic sulphonic acid as catalyst and in the presence of small grains of an insert material in the reaction medium or (b) a halogenated hydrocarbon solvent together with a hydrohalogen acid an organic sulphonic acid as catalyst and in the presence of an epimeric distribution modifier.