Hydrogenation of vermistatin, a metabolite of Penicillium vermiculatum, afforded cis- and trans-3-(2'-carboxy-4',6'-dimethoxybenzyl)-6-propyltetrahydro-4H-pyran-4-one and 4,6-dimethoxy-3-(4'-propylcyclopentanon-2'-yl)phthalide. The latter compound was found to be the strongest inhibitor of RNA synthesis in P388 leukemia cells of all compounds tested.
New Vermistatin Derivatives Isolated from Penicillium simplicissimum