New furoisocoumarins and isocoumarins from the mangrove endophytic fungusAspergillussp. 085242.
The chemical investigation of the mangrove endophytic fungusAspergillussp. 085242 afforded eight isocoumarin derivatives1-8and one isoquinoline9. Asperisocoumarins A and B (1and2) were new furoisocoumarins, and asperisocoumarins E and F (5and6) were new isocoumarins. Their structures were established by analysis of their spectroscopic data and the absolute configuration of compound2was unambiguously determined by X-ray structure analysis and ECD calculation. Moreover, the absolute configurations of compounds3-5were assigned by comparison of their ECD spectra with isocoumarins described in the literature. Asperisocoumarins C and D (3and4) were fully characterized spectroscopically and isolated from a natural source for the first time. Asperisocoumarins A-D (1-4) related to the class of furo[3,2-h]isocoumarins are rarely occurring in natural sources. Compounds2,5, and6showed moderate α-glucosidase inhibitory activity with IC50of 87.8, 52.3, and 95.6 μM, respectively. In addition, compounds1and3exhibited weak radical scavenging activity with EC50values of 125 and 138 μM, respectively.
School of Chemistry and Chemical Engineering, Sun Yat-Sen University, No. 135 of Xingang West Road, Guangzhou, 510275, China.|Shenzhen Academy of Metrology and Quality Inspection, No. 144 of Minkan Road, Minzhi Street, Longhua District, Shenzhen, 518102, China.
Ze'en
Z
Xiao
School of Chemistry and Chemical Engineering, Sun Yat-Sen University, No. 135 of Xingang West Road, Guangzhou, 510275, China.
Senhua
S
Chen
School of Chemistry and Chemical Engineering, Sun Yat-Sen University, No. 135 of Xingang West Road, Guangzhou, 510275, China.
Runlin
R
Cai
School of Chemistry and Chemical Engineering, Sun Yat-Sen University, No. 135 of Xingang West Road, Guangzhou, 510275, China.
Shao'e
S
Lin
Key Laboratory of Combinatorial Biosynthesis and Drug Discovery, Ministry of Education of China, School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071, China.
Kui
K
Hong
School of Chemistry and Chemical Engineering, Sun Yat-Sen University, No. 135 of Xingang West Road, Guangzhou, 510275, China.
Zhigang
Z
She
Aspergillus; DPPH·; furoisocoumarin; isocoumarin; α-glucosidase