.DELTA..sup.9(11) - And .DELTA..sup.16 -21-chloro-20-keto steroids of
申请人:Schering Aktiengesellschaft
公开号:US04404141A1
公开(公告)日:1983-09-13
.DELTA..sup.16 - and .DELTA..sup.17 -21-chloro-20-keto steroids of the formula ##STR1## wherein n is 1 or 2, C.sub.1 C.sub.2 and C.sub.9 C.sub.11 represent a CC-single or CC-double bond, R.sub.1 is H or OH, R.sub.2 is H or CH.sub.3, R.sub.3 is H or F wherein, when R.sub.3 =F, C.sub.9 C.sub.11 is a CC-single bond, and R.sub.4 is H, CH.sub.3, or F, are valuable intermediates for preparation of highly effective, known steroids. A process for preparing these compounds involves heating the corresponding 11.beta.- and/or 17.alpha.- or 17a.alpha.-nitrooxy-21-mesyloxy-20-keto steroids with lithium chloride in a dipolar aprotic solvent at temperatures above room temperature.