Δ16 and Δ17-21-chloro-20-keto steroids of the formula
wherein
n is 1 or 2,
C1C2 and C9C11 represents a CC-single or CC-double bond,
R1 is H or OH,
R2 is H or CH3,
R3 is H or F wherein, when R3 = F, C9C11 is a CC-single bond, and
R4 is H, CH3, or F,
are valuable intermediates for preparation of highly effective, known steroids.
A process for preparing these compounds involves heating the corresponding 11ß- and/or 17a- or 17aa- nitrooxy-21-mesyloxy-20-keto steroids with lithium chloride in a dipolar aprotic solvent at temperatures above room temperature.
式中Δ16 和Δ17-21-
氯-20-
酮类固醇
式中
n 是 1 或 2、
C1C2和C9C11代表CC-单键或CC-双键、
R1 是 H 或 OH
R2 是 H 或
CH3、
R3 是 H 或 F,其中,当 R3 = F 时,C9C11 是 CC 单键,以及
R4 是 H、 或 F、
是制备高效、已知类
固醇的重要中间体。
制备这些化合物的工艺包括在室温以上的温度下,在双极性非
丙烷溶剂中用
氯化锂加热相应的 11ß- 和/或 17a- 或 17aa- 硝基氧基-21-甲酰氧基-20-
酮类固醇。