title: Chaetoglobosin U, a cytochalasan alkaloid from endophytic Chaetomium globosum IFB-E019.
abstract: A new cytotoxic cytochalasan-based alkaloid named chaetoglobosin U (1), along with four known analogues, chaetoglobosins C (2), F (3), and E (5) and penochalasin A (4), has been characterized from the EtOAc extract of a solid culture of Chaetomium globosum IFB-E019, an endophytic fungus residing inside the stem of healthy Imperata cylindrica. The structure of chaetoglobosin U was determined through correlative analyses of its UV, IR, CD, MS, and 1D ((1)H and(13)C NMR and DEPT) and 2D NMR (COSY, NOESY, HMQC, and HMBC) data. Chaetoglobosin U (1) exhibited cytotoxic activity against the human nasopharyngeal epidermoid tumor KB cell line with an IC(50) value of 16.0 microM, comparable to that (14.0 microM) of 5-fluorouracil co-assayed as a positive reference. The known analogues 2-5 were moderately active to the cell line, with IC(50) values of 34.0, 52.0, 48.0, and 40.0 microM, respectively.
authors.affiliation: Institute of Functional Biomolecules, State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, People's Republic of China.
authors.forename: Gang
authors.initials: G
authors.lastname: Ding
authors.forename: Yong C
authors.initials: YC
authors.lastname: Song
authors.forename: Jing R
authors.initials: JR
authors.lastname: Chen
authors.forename: Chen
authors.initials: C
authors.lastname: Xu
authors.forename: Hui M
authors.initials: HM
authors.lastname: Ge
authors.forename: Xiao T
authors.initials: XT
authors.lastname: Wang
authors.forename: Ren X
authors.initials: RX
authors.lastname: Tan
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002597:Chaetomium / Q000737:chemistry*; D002681:China; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D026121:Indole Alkaloids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D007624:KB Cells; D015394:Molecular Structure
chemical_list: D000970:Antineoplastic Agents; D026121:Indole Alkaloids; C019290:chaetoglobosins