Coumarins and acridone alkaloids with α-glucosidase inhibitory and antioxidant activity from the roots of Paramignya trimera

• Published in: Phytochemistry letters 2020-02, Vol.35, p.94-98
• Main Authors: Trinh, Duong H., Tran, Phuong T., Trinh, Binh T.D., Nguyen, Hieu T., Nguyen, Hiep D., Ha, Ly D., Nguyen, Lien-Hoa D.
• Format: Article
• Language: English
• Subjects: Acridone alkaloids; Coumarins; DPPH; Paramignya trimer; α-Glucosidase
• ISSN: 1874-3900; 1876-7486
• DOI: 10.1016/j.phytol.2019.10.010

[Display omitted] •Two new coumarins, paramicoumarins A and B, and a new alkaloid, paramiacridone, were isolated from Paramignya trimera.•Paramiacridone and paramicoumarin B showed strong α-glucosidase inhibitory effect.•The acridone alkaloid glycocitrin III exhibited the highest antioxidant activity. Three new compounds comprising two coumarins, paramicoumarins A (1) and B (2), and an acridone alkaloid, paramiacridone (3), together with seven known compounds, were isolated from the n-hexane extract of the roots of Paramignya trimera (Rutaceae). Their structures were elucidated using spectroscopic methods, mainly 1D and 2D NMR. α-Glucosidase inhibition and DPPH radical scavenging activity of the compounds and fifteen other compounds previously isolated from the roots of this plant were evaluated. Most of the compounds exhibited stronger α-glucosidase inhibitory activity than acarbose, the positive control (IC50 = 223.0 μM), and the new compounds paramiacridone (3) and paramicoumarin B (2) showed good inhibitory effect (IC50 = 62.5 and 65.5 μM, respectively). In the DPPH test for radical scavenging activity, the acridone alkaloid glycocitrin III (17) exhibited the highest antioxidant activity (IC50 = 84.2 μM) (compared with the positive control, ascorbic acid, IC50 = 152.7 μM).