title: Heptaketides with antiviral activity from three endolichenic fungal strains Nigrospora sp., Alternaria sp. and Phialophora sp.
abstract: Two new heptaketides, (+)-(2S,3S,4aS)-altenuene (1a) and (-)-(2S,3S,4aR)-isoaltenuene (2a), together with six known compounds, (-)-(2R,3R,4aR)-altenuene (1b), (+)-(2R,3R,4aS)-isoaltenuene (2b), 5'-methoxy-6-methyl-biphenyl-3,4,3'-triol (3), alternariol (4), alternariol-9-methyl ether (5), and 4-hydroxyalternariol-9-methyl ether (6) were isolated from the EtOAc extract of an endolichenic fungal strain Nigrospora sphaerica (No.83-1-1-2). Compounds 1a and 1b were separated from enantiomers 1 by chiral HPLC, and so were 2a and 2b from enantiomers 2. Interestingly, 1-6 were also obtained from other two endolichenic fungal strains Alternaria alternata (No.58-8-4-1) and Phialophora sp. (No.96-1-8-1). The structures of 1-6 were elucidated by means of MS, HR-MS, NMR, and X-ray diffraction. Furthermore, the absolute configurations of 1a-2b were determined by CD experiments and CD calculation. Of these compounds, 4 and 5 showed antiviral activity against herpes simplex virus (HSV) in vitro, with IC(50) values of 13.5 and 21.3 μM, and with selective index (SI) values of 26.5 and 17.1, respectively.
authors.affiliation: Institute of Traditional Chinese Medicine and Natural Products, College of Pharmacy, Jinan University, Guangzhou, PR China.
authors.forename: Jun-Wei
authors.initials: JW
authors.lastname: He
authors.forename: Guo-Dong
authors.initials: GD
authors.lastname: Chen
authors.forename: Hao
authors.initials: H
authors.lastname: Gao
authors.forename: Fan
authors.initials: F
authors.lastname: Yang
authors.forename: Xiao-Xia
authors.initials: XX
authors.lastname: Li
authors.forename: Tao
authors.initials: T
authors.lastname: Peng
authors.forename: Liang-Dong
authors.initials: LD
authors.lastname: Guo
authors.forename: Xin-Sheng
authors.initials: XS
authors.lastname: Yao
mesh_terms: D000528:Alternaria / Q000737:chemistry*; D000998:Antiviral Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D001688:Biological Products / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D007783:Lactones / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D008011:Lichens; D003904:Mitosporic Fungi / Q000737:chemistry*; D015394:Molecular Structure; D010676:Phialophora / Q000737:chemistry*; D061065:Polyketides / Q000737:chemistry / Q000302:isolation & purification; D018139:Simplexvirus / Q000187:drug effects*; D013237:Stereoisomerism
chemical_list: D000998:Antiviral Agents; D001688:Biological Products; D007783:Lactones; D061065:Polyketides; C005197:alternariol; C018206:alternariol monomethyl ether