The rugulovasines A and B (lqb), which were first isolated from Penicillium concavorugulosiuml and then from Penicillium islandicum, 2 represent novel structural types within the family of the Ergot alkaloid^.^ Interestingly, the rugulovasines A and B were isolated in racemic form, and they were also observed to interconvert upon warming. To account for these facts, the mechanism depicted in Scheme I was proposed, in which la ...
