title: (1)H and (13)C NMR signal assignments of paecilin A and B, two new chromone derivatives from mangrove endophytic fungus Paecilomyces sp. (tree 1-7).
abstract: Two new natural products, named paecilin A (1) and B (2), together with two known compounds secalonic acid D (3) and (11)-cytochalasa-6(12),13-diene-1,21-dione-16,18-dimethyl-7-hydroxy-10-phenyl-(7S*,13E,16S*,18S*) (4), were isolated from the mangrove endophytic fungus, Paecilomyces sp. (tree 1-7) from the South China Sea. 1D and 2D NMR experiments including COSY, HMQC, and HMBC were used for the determination of their structures. In our cytotoxicity assays, secalonic D (3) showed cytotoxicity toward KB cells with IC(50) < 1 microg ml(-1) and inhibiting human topoisomerase I with IC(50) at 0.16 micromol ml(-1). 1, 2, and 4 showed no activity to KB cells.
authors.affiliation: School of Chemistry and Chemical Engineering, SunYat-Sen (Zhongshan) University, Guangzhou 510275, PR China.
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Guo
authors.forename: Zhigang
authors.initials: Z
authors.lastname: She
authors.forename: Changlun
authors.initials: C
authors.lastname: Shao
authors.forename: Lu
authors.initials: L
authors.lastname: Wen
authors.forename: Fan
authors.initials: F
authors.lastname: Liu
authors.forename: Zhonghui
authors.initials: Z
authors.lastname: Zheng
authors.forename: Yongcheng
authors.initials: Y
authors.lastname: Lin
mesh_terms: D001578:Benzopyrans / Q000737:chemistry*; D004354:Drug Screening Assays, Antitumor; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005285:Fermentation; D006801:Humans; D007624:KB Cells; D007783:Lactones / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D010143:Paecilomyces / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D059004:Topoisomerase I Inhibitors; D044004:Xanthones / Q000032:analysis
chemical_list: D001578:Benzopyrans; D004791:Enzyme Inhibitors; D007783:Lactones; D059004:Topoisomerase I Inhibitors; D044004:Xanthones; C523427:paecilin A; C523428:paecilin B; C009218:secalonic acid