Cucurbitane-Type Triterpene Glycosides from Momordica charantia and Their α-Glucosidase Inhibitory Activities

ABSTRACT: Ten cucurbitane-type triterpene glycosides, including five new compounds named charantosides H (1), J (2), K (3), momorcharacoside A (4), goyaglycoside-l (5), and five known compounds (6–10), were isolated from the EtOAc extract of Momordica charantia fruits. The chemical structures of these compounds were identified by 1D and 2D NMR and HRESIMS spectroscopic analyses. Configurations of new compounds were determined by ROESY correlations and comparison of their (13)C NMR data with literature reported values. All compounds were evaluated for their inhibition against α-glucosidase, in which compounds 2, 5, 7, 8, 9 showed moderate inhibitory activities with IC(50) values ranging from 28.40 to 63.26 μM comparing with the positive control (acarbose, IC(50) 87.65 ± 6.51 μM). GRAPHIC ABSTRACT: [Image: see text] ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13659-020-00241-5) contains supplementary material, which is available to authorized users.