An efficient synthesis of 5alpha-androst-1-ene-3,17-dione.

5alpha-Androst-1-ene-3,17-dione (5) as a prodrug of 1-testosterone (4) was prepared in four steps from 17beta-Acetoxy-5alpha-androstan-3-one (stanolone acetate) (1) in high yield. Thus, stanolone acetate (1) was brominated in the presence of hydrogen chloride in acetic acid to give 17beta-acetoxy-2-bromo-5alpha-androstan-3-one (2), which underwent dehydrobromination using lithium carbonate as base with lithium bromide as an additive to give 17beta-acetoxy-5alpha-androst-1-en-3-one (3) in almost quantitative yield with 97% of purity. Compound (3) was hydrolyzed with sodium hydroxide to give 17beta-hydroxy-5alpha-androst-1-en-3-one (4,1-testosterone), which was oxidized with chromium trioxide to afford 5alpha-androst-1-ene-3,17-dione (5). The overall yield of 5 was 78.2% with purity of 99%. In this method, the formation of 4-ene was diminished when 1-ene was introduced, and its mechanism was also discussed.

Identifying N-nitrosofenfluramine in a nutrition supplement.

The analytical data for identifying an unknown substance that was found in a nutrition supplement is presented. The unknown substance is purified using thin-layer chromatography and then measured using high-resolution mass spectrometry (HRMS) giving the exact mass from which the structure of the unknown substance was proposed. The procedure for synthesizing N-nitrosofenfluramine from fenfluramine is described. The extracted, synthesized, and standard N-nitrosofenfluramine are compared using HRMS, high-performance liquid chromatography (HPLC)-MS, HPLC-UV, Fourier transform IR spectroscopy, gas chromatography-MS, TLC, and NMR (1H NMR and 13C NMR). All analytical data obtained confirm that the unknown peak in the nutrition supplement is N-nitrosofenfluramine and that the synthetic procedure described can easily provide the N-nitrosofenfluramine reference substance for identification.