905-30-6Relevant academic research and scientific papers
NAD(P)H Models XV. Reduction of Δ4-3-ketosteroids via their iminium salts, by 1,4-dihydropyridine derivatives
Gase, Ronald A.,Pandit, Upendra K.
, p. 334 - 340 (2007/10/02)
Pyrrolidinium salts derived from a series of 17-substituted Δ4-3-ketosteroids are reduced by 1-benzyl-1,4-dihydronicotinamide (BNAH) and 2,6-dimethyl-3,5-diethoxycarbonyl-1,4-dihydropyridine (Hantzsch ester, 1 eq.) to the corresponding isomeric 5α- and 5β-enamines which hydrolyse to the corresponding 3-ketosteroids.In the case of the Hantzsch ester reduction, proton transfer from the oxidized Hantzsch ester to the enamine results in the formation of iminium salts, which are further reduced to the corresponding ammonium salts.Mechanistic, stereochemical and biochemical implications of the reactions are discussed.
Process for the preparation of 17β-hydroxy-3-oxo-17α-pregn-4-ene-21-carboxylic acid γ-lactone
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, (2008/06/13)
A new process for the preparation of 17β-hydroxy-3-oxo-17α-pregn-4-ene-21-carboxylic acid γ-lactone is described herein. The process makes use of androst-4-ene-3,17-dione as the starting material and 17α-ethynyl-17β-hydroxyandrost-4-en-3-one as an early intermediate.
