A synthesis of cyclohexanoid butenolides isolated from Sinomenium acutum

Starting from an enantiopure building-block serving as the chiral equivalent of 4-hydroxycyclohexa-2,5-dien-1-one, a diastereocontrolled synthesis of four cyclohexanoid butenolides has been investigated. The inherent convex-face selectivity exerted by the chiral building block was a key aspect of this method which afforded three of the five known butenolides, with only one losing its original chiral integrity during the conversion.