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The reduction of α-ketols (the alcoholic function being exclusively on a tertiary carbon) by treatment with hydriodic acid in acetic acid has been investigated. It will be shown that many representatives lead to rearrangements while similar analogs suffer straight reduction. The reason for the differences in the reaction paths and the underlying mechanisms will be discussed.
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To ascertain the exact fate of the C-19 during the biological conversion of androgens to estrogens it was necessary to synthesize C-19 labeled androgens. The conversion of 19-tosyloxyandrost-4-ene-3,17-dione to 5, 19-cycloandrostane-3,17-dione by various methods and opening of the cyclopropane ring with H3 2 O in presence of a trace of acid or base to androst-4-ene-3,17-dione-19-H3 will be discussed. Preparation of 19-C14 material from methyl 17-acetoxy-3,5-seco-4,19-bisnorandrostan-5-one-3-oate will also be described.
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Une route simple et efficace vers l'acide 3β-hydroxy-20β-acétoxy-9-oxo-9, 12-séco-11-nor-5 α-pregnan-12-oïque et la transformation de ce produit en 11-aza stéroïdes sont décrites. La conversion d'un intermédiaire 9, 11-insaturé 12-cétonique en dérivé 11, 12-séco 11-aldéhyde 12-acide est rapportée. Nous signalons aussi l'addition, en position 16 α, d'une molécule d'éthylène glycol sur une 12, 20-dicétone 16, 17-insaturée, sous l'influence d'un catalyseur acide.
