title: Isolation and photoinduced conversion of 6-epi-stephacidins from Aspergillus taichungensis.
abstract: Three prenylated indole alkaloids with a rare anti bicyclo-[2.2.2]diazaoctane core ring (5-7) were isolated from Aspergillus taichungensis. The structures including absolute configurations were elucidated based on NMR, X-ray, and CD methods. (+)-Versicolamides B and C (8-9) which contain a spiro-center, together with seven analogues (7, 10-15), were isolated as photoinduced conversion products of 6. Biological evaluation indicated that 6 and 7 exhibited significant cytotoxicities with IC50 values in the low micromolar range.
authors.affiliation: Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao, 266003, PR China.
authors.forename: Shengxin
authors.initials: S
authors.lastname: Cai
authors.forename: Yepeng
authors.initials: Y
authors.lastname: Luan
authors.forename: Xianglan
authors.initials: X
authors.lastname: Kong
authors.forename: Tianjiao
authors.initials: T
authors.lastname: Zhu
authors.forename: Qianqun
authors.initials: Q
authors.lastname: Gu
authors.forename: Dehai
authors.initials: D
authors.lastname: Li
mesh_terms: D001230:Aspergillus / Q000737:chemistry*; D018360:Crystallography, X-Ray; D026121:Indole Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry* / Q000302:isolation & purification*; D020128:Inhibitory Concentration 50; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D054876:Prenylation; D013237:Stereoisomerism
chemical_list: D026121:Indole Alkaloids; C529010:versicolamide B; C583647:versicolamide C