Studies On The Secondary Metabolites Of Aspergillus Flavipes And Penicillium Camemberti

Fungi are one of the most important sources of the lead compounds in drug discovery.Fungi have many metabolic pathways as revealed by the genomic analysis.Fungi with many survival strategies living in special environment are one of the most promising source of biologically active compounds.We studied the secondary metabolites of Aspergillus flavipes that isolated from intertidal zone of the Yangtze river and Penicillium camemberti that obtained from the southwestern region of the Pacific Ocean.This dissertation mainly introduces the chemical constituents of A.flavipes and P.camemberti,involving isolation,structure elucidation,and biological evaluation of secondary metabolites utilizing a variety of chromatographic and spectroscopic techniques as well as cell/enzyme-based bioassays.A.flavipes was phytochemically investigated and led to the isolation and characterization of 40 compounds,including 20 new ones.Compounds 1 and 2 represent the first examples of cytochalasans with cyclopenta[c]pyrrol-one and 5/6/6/5/6 pentacyclic core.Compounds 3-6 represent a novel class of cytochalasans characterized by the cross-coupling of aspochalasin and epicoccine dimer moieties.The marine fungus,Penicillium camemberti was phytochemically investigated and led to isolation and characterization of 3 cyclopiazonic acid(CPA)alkaloids including a new one together with 6 other compounds.Selected compounds were tested for their cytotoxic activities against five human cancer cell lines,and the new CPA alkaloid was valuated for its anti-HIV activity.The study of A.flavipes and P.camemberti,which lead to the isolation of a large number of cytochalasans and CPA alkaloids,greatly enriched the structural diversity of cytochalasans and laid a foundation for the further research.