title: Synthesis and reduction of steroid C-20 alkylidene cyanoacetates.
abstract: The geometry of the condensation products between ethyl cyanoacetate and 20-ketosteroids (5 alpha-pregnane-20-one, 3 beta-hydroxypregn-5-en-20-one and 3 beta-acetoxypregn-5-en-20-one) was established by NMR spectra. Reduction of these steroid C-20 alkylidene cyanoacetates was shown to afford one of the two possible 20-C epimers, which seen to correspond to the 20 beta-methyl configuration.
mesh_terms: D000085:Acetates / Q000138:chemical synthesis*; D055598:Chemical Phenomena; D002621:Chemistry; D007664:Ketosteroids; D009570:Nitriles / Q000138:chemical synthesis; D011278:Pregnanes / Q000138:chemical synthesis*; D011284:Pregnenolone / Q000138:chemical synthesis; D013237:Stereoisomerism
chemical_list: D000085:Acetates; D007664:Ketosteroids; D009570:Nitriles; D011278:Pregnanes; D011284:Pregnenolone; C007659:ethyl cyanoacetate