title: Chaetoglobosin Vb from endophytic Chaetomium globosum: absolute configuration of chaetoglobosins.
abstract: One new cytochalasan alkaloid, chaetoglobosin V(b) (1), together with two structurally related known compounds, chaetoglobosin V (2) and chaetoglobosin G (3), was isolated from the ethyl acetate extract of a culture of the endophytic fungus Chaetomium globosum, associated with the leaves of Ginkgo biloba tree. The structures of the isolated compounds were elucidated by spectroscopic methods including 1D and 2D NMR and mass spectrometry. The absolute configuration of chaetoglobosin V(b) (1) was established by means of electronic circular dichroism (CD) spectroscopy, on the basis of the comparison between the CD spectrum of (+)-1 with that calculated with time-dependent density functional theory method for a simplified model. The correlation between compounds 1-3 was demonstrated by a biomimetic transformation of chaetoglobosin G (3) under mild conditions in chaetoglobosins V and V(b) (1 and 2). The isolated metabolites were tested against some phytopathogens.
authors.affiliation: Shaanxi Engineering Center of Bioresource Chemistry & Sustainable Utilization, College of Science, Northwest A&F University, Yangling, People's Republic of China.
authors.forename: Min
authors.initials: M
authors.lastname: Xue
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.forename: Jin-Ming
authors.initials: JM
authors.lastname: Gao
authors.forename: He
authors.initials: H
authors.lastname: Li
authors.forename: Jun-Mian
authors.initials: JM
authors.lastname: Tian
authors.forename: Gennaro
authors.initials: G
authors.lastname: Pescitelli
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D002597:Chaetomium / Q000737:chemistry*; D060026:Endophytes / Q000737:chemistry*; D000431:Ethanol / Q000737:chemistry; D026121:Indole Alkaloids / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D008958:Models, Molecular; D008968:Molecular Conformation
chemical_list: D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D026121:Indole Alkaloids; D000431:Ethanol; C019290:chaetoglobosins