Three dimeric naphtho-γ-pyrones from the mangrove endophytic fungus Aspergillus tubingensis isolated from Pongamia pinnata.
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.
Huang
Hong-Bo
HB
School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou, P R China.
Feng
Xiao-Jun
XJ
Liu
Lan
L
Chen
Bin
B
Lu
Yong-Jun
YJ
Ma
Lin
L
She
Zhi-Gang
ZG
Lin
Yong-Cheng
YC
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
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