Enzymatic <i>cis-</i>Decalin Formation in Natural Product Biosynthesis

Abstract

Stereoselective synthesis of <i>cis-</i>decalin structures using [4 + 2] cycloaddition is challenging. We explored the biosynthetic pathway of the fungal natural product fischerin (<b>1</b>) to identify a new pericyclase FinI that can catalyze such a reaction. The cocrystal structure of FinI, a predicted <i>O-</i>methyltransferase, with the product and SAM provides insight into <i>cis-</i>decalin formation in nature.