Biotransformation of antifungal ilicicolin H

The biotransformation of natural product is a powerful method for the functionalization of small molecules, particularly oxidation of unactivated carbons. Ilicicolin H is a tetracyclic antifungal agent consisting of a decalin moiety and a phenyl-pyridone unit. The lipophilic decalin unit is devoid of any heteroatoms. The biotransformation of ilicicolin H led to the formation of eight new oxidized products. The predominant product formed was the result of selective oxidation of the C-19 methyl group of the decalin ring leading to the C-19 hydroxy methyl analog. While these compounds showed poorer activity than ilicicolin H, the new functional groups did provide the opportunity for further chemical modifications and optimization.