THE MICROBIOLOGICAL TRANSFORMATION OF TWO ENT-16β,17-EPOXYKAURANE DERIVATIVES BY GIBBERELLA FUJIKUROI

Article abstract of DOI:10.1016/S0031-9422(00)90345-5

The biotransformation of ent-16β,17-epoxy-7α-hydroxykaurane by Gibberella fujikuroi affords ent-7α,11α,16β,17-tetrahydroxykaurane and ent-7α,9α,16β,17-tetrahydroxykaurane.These results indicated that the presence of the 16α,17-diol group, into which the 16α,17-epoxy is transformed in the medium, imhibits oxidation at C-19 and favours hydroxylation at C-11(β).Incubation of ent-16β,17-epoxykauran-19-oic acid, via the 16α,17-diol, gave the 7-aldehyde of 16α,17-dihydroxy-GA₁₂. - Key words: Gibberella fujikuroi; biotransformations; diterpenes; ent-16β,17-epoxy-7α-hydroxykaurane; ent-16β,17-epoxykauran-19-oic acid; ent-7α,16β,17-trihydroxykaurane; ent-16β,17-dihydroxykauran-19-oic acid.