| pubmed-article:19088760 | pubmed:abstractText | The chemical synthesis of (22R,23R)-3beta-hydroxy-22,23-epoxy-5alpha-ergost-8(14)-en-15-one from (22E)-3beta-acetoxy-5alpha-ergosta-7,14,22-triene was improved. The stages of obtaining and isomerizing (22E)-3beta-acetoxy-14alpha,15alpha-epoxy-5alpha-ergosta-7,22-diene were optimized. The introduction of the (22R,23R)-epoxide cycle was carried out by a basic treatment of intermediate (22S,23R)-3beta,23-diacetoxy-22-iodo-5alpha-ergost-8(14)-en-15-one. In cells of human mammary gland carcinoma MCF-7 (22R,23R)-3beta-hydroxy-22,23-epoxy-5alpha-ergost-8(14)-en-15-one showed a high toxicity (TC(50) = 0.4 +/- 0.1 microM for 48-h incubation in serum-free medium). | lld:pubmed |
