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5-chloro-5 beta-cholestane, the first simple 5 beta-chlorosteroid
Abstract:
The life, times, and the main achievements in the steroid field of Julius Mauthner are briefly described. Three attempts by the author to isolate and to characterise 5-chloro-5 beta-cholestane are enumerated; the last attempt was successful, and furnished 5-chloro-5 beta-cholestane in two polymorphic forms: m.p. 72-75 degrees C, [alpha]20D + 37 degrees (labile above 0 degrees C) and m.p. 94-95 degrees C, [alpha]20D + 34 degrees (stable up to 75 degrees C). Possible mechanisms of the spontaneous, solid-state dehydrochlorination above 0 degrees C of the polymorph, m.p. 72-75 degrees C, are discussed.
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