that the presence of a 7β-acetoxy group does not inhibit the fungal oxidation of C-19 in 7β-acetoxy-ent-kaur-16-ene, but avoids the ring B contraction that leads to the gibberellins and the 6β-hydroxylation necessary for the formation of seco-ring B ent-kaurenoids. The biotransformation of 7β-acetoxy-ent-trachylobane (trachinol acetate) (27) only led to the formation of 7β-acetoxy-18-hydroxy-ent-trachylobane
Candol A (7β-hydroxy-ent-kaur-16-ene) (6) 被藤黑赤霉有效地转化为
赤霉素植物激素。在这项工作中,这种真菌对其
乙酸盐的
生物转化导致了 7β-乙酰氧基-ent-kaur-16-en-19-oic酸 (3) 的形成,其相应的醇是
生物合成中的短寿命中间体在这种真菌中的
赤霉素和 seco-ring ent-kaurenoids。该化合物的进一步
生物转化导致 3β-位羟基化,得到 7β-乙酰氧基-3β-羟基-ent-kaur-16-en-19-
油酸 (14),然后是 2β-或 18-羟基化这种代谢物。Epiandicandiol 7β-monoacetate (7β-acetoxy-18-hydroxy-ent-kaur-16-ene) (10) 的孵育也产生 19-羟基化形成 18,19 二醇 (20),后者被氧化得到相应的 C-18 或 C-19 酸。这些结