title: Three dimeric naphtho-γ-pyrones from the mangrove endophytic fungus Aspergillus tubingensis isolated from Pongamia pinnata.
abstract: Three new dimeric naphtho-γ-pyrones, named rubasperone A (1), rubasperone B (2), and rubasperone C (3), together with two known compounds, rubrofusarin (4) and rubrofusarin B (5), were isolated from the mangrove endophytic fungus Aspergillus tubingensis (GX1-5E). Their structures were determined by spectroscopic methods, including IR, MS, and 1D and 2D NMR. The structures of 1 and 2 were further confirmed by X-ray crystallography. In the bioactivity assays against tyrosinase and α-glucosidase, rubrofusarin (4) exhibited moderate tyrosinase inhibitory activity, with an IC(50) value of 65.6 µM, and rubasperone C (3) showed mild α-glucosidase inhibitory activity, with an IC(50) value of 97.3 µM.
authors.affiliation: School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou, P R China.
authors.forename: Hong-Bo
authors.initials: HB
authors.lastname: Huang
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Feng
authors.forename: Lan
authors.initials: L
authors.lastname: Liu
authors.forename: Bin
authors.initials: B
authors.lastname: Chen
authors.forename: Yong-Jun
authors.initials: YJ
authors.lastname: Lu
authors.forename: Lin
authors.initials: L
authors.lastname: Ma
authors.forename: Zhi-Gang
authors.initials: ZG
authors.lastname: She
authors.forename: Yong-Cheng
authors.initials: YC
authors.lastname: Lin
mesh_terms: D001230:Aspergillus / Q000737:chemistry*; D004791:Enzyme Inhibitors / Q000302:isolation & purification* / Q000494:pharmacology; D065089:Glycoside Hydrolase Inhibitors; D033641:Millettia / Q000382:microbiology*; D015394:Molecular Structure; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors*; D009281:Naphthalenes / Q000737:chemistry / Q000302:isolation & purification*; D018517:Plant Roots / Q000382:microbiology; D011753:Pyrones / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D065089:Glycoside Hydrolase Inhibitors; D009281:Naphthalenes; D011753:Pyrones; C557806:rubasperone A; C557807:rubasperone B; C557808:rubasperone C; C015497:rubrofusarin; D014442:Monophenol Monooxygenase