The preparation and bioactivities of (−)-isovelleral1,2 Original Research Article

The resolution of synthetic (±)-isovelleral (1), via chromatographic separation of the two diastereomers of the (−)-menthoxyacetic acid diester of the corresponding (±)-diol (3), yielded both enantiomers of the bioactive fungal metabolite (+)-isovelleral (1). While the antimicrobial and cytotoxic activities of the two enantiomers are comparable, natural (+)-1 is approximately 10 times more mutagenic towards Amesʹ tester strain TA98 than (−)-1. The two enantiomers of the cyclopropane ring isomer 2 also possess negligible mutagenicity compared to (+)-1. Both (+)-1 and (−)-1 have the same affinity for the vanilloid receptor, but significant different affinity for the dopamine D1 receptor.