Introduction d'une fonction azotée en 14β du noyau stéroide. Application à la préparation d'une molécule cardioactive, le 14β-amino-5β-prégnane-3β,20β-diol, à partir de la progestérone et de l'acide désoxycholique
Introduction d'une fonction azotée en 14β du noyau stéroide. Application à la préparation d'une molécule cardioactive, le 14β-amino-5β-prégnane-3β,20β-diol, à partir de la progestérone et de l'acide désoxycholique
Numerous bioactive glycosteroids are characterized by aglycones bearing a 14 beta-hydroxy pregnane skeleton like boucerin and isoramanone. In general, the syntheses of the latter are achieved by acidic hydrolysis of the corresponding glycosteroids. These aglycones were also obtained by a combined Norrish type I-Prins reaction starting from the corresponding 12-keto-pregnane derivatives. However, for the Norrish-Prins reaction, no reports describe the influence of the A/B ring junction (cis or trans or Delta(5,6) double bond) or the influence of the substitution pattern at position 20. Herein, we describe the use of Norrish type I-Prins reactions to synthesize isoramanone and boucerin derivatives and their A/B cis and trans analogs. The influence of the parameters mentioned above is also presented. These studies showed that the A/B ring junction has little influence on the Norrish type I-Prins reaction but that the substitution pattern at position 20 is important. The presence of a dioxolane group induced not only the formation of the desired 14 beta-hydroxy pregnane derivatives in the highest yields but also the formation of new spiro derivatives. (C) 2011 Elsevier Inc. All rights reserved.
ADEOTI, S. B.;CHARPENTIER, B.;MONTAGNAC, A.;CHIARONI, A.;RICHE, C.;PAIS, +, TETRAHEDRON, 45,(1989) N2, C. 3717-3730
作者:ADEOTI, S. B.、CHARPENTIER, B.、MONTAGNAC, A.、CHIARONI, A.、RICHE, C.、PAIS, +
DOI:——
日期:——
Introduction d'une fonction azotée en 14β du noyau stéroide. Application à la préparation d'une molécule cardioactive, le 14β-amino-5β-prégnane-3β,20β-diol, à partir de la progestérone et de l'acide désoxycholique