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The synthesis of androstane brassinosteroid analogues with alpha-azido acid ester groups in position 17beta
Jaroslava Hnilickova1, Ladislav Kohout, Enric Capdevila
1Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague 6, Czech Republic.
Abstract:
Androstane brassinosteroid analogues with alpha-azido acid ester groups in position 17beta were synthesized from 2alpha,3alpha,17beta-trihydroxy-5alpha-androstan-6-one after the protection of the 2alpha,3alpha-diols upon treatment with the corresponding alpha-azido acid and the subsequent deprotection of the diol grouping. Six new castasterone analogues were prepared. The biological activities were evaluated in two bioassays: a rice lamina inclination test and bean second internode bioassays. The activities of the new analogues differ in these two bioassays.
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