RESUMO
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.
Assuntos
Androstanos/química , Androstanos/síntese química , Azidas/química , Ésteres , Hidróxidos/químicaRESUMO
New androstane brassinosteroids with 17beta-ester groups - butyrates, heptafluorobutyrates, and laurates (4-18) - were prepared. Brassinolide activity was evaluated using both the bean second internode bioassay and the rice lamina inclination test. Brassinosteroid 16 was found to be the most active by the bean second internode bioassay. This activity in the bean second internode bioassay corresponded with the field yield, while the RLIT bioassay does not.