Synthesis and Biotransformation of Bicyclic Unsaturated Lactones with Three or Four Methyl Groups

The aim of this study was to obtain new unsaturated lactones by chemical synthesis and their microbial transformations using fungal strains. Some of these strains were able to transform unsaturated lactones into different hydroxy or epoxy derivatives. Strains of and gave products with a hydroxy group introduced into a tertiary carbon, while the strain hydroxylated primary carbons. The strain hydroxylated both substrates in an allylic position. Using the and strains led to the obtained epoxylactones. The structures of all lactones were established on the basis of spectroscopic data.