New alkaloids from the noni juice with potential α-glucosidase inhibitory activity

August 16, 2021

Title

New alkaloids from the noni juice with potential α-glucosidase inhibitory activity

Author

Bin Zhang

Year

2021

Journal

Fitoterpia

Abstract

Four new alkaloids, nonialkaloids A–D (1–4) and six known analogues (5–10) were isolated from the noni juice. Among the new compounds, 1 and 2 are indole alkaloids with a seven-membered fused N-heterocyclic ring, 3 and 4 are quaternary ammonium derivatives. The structures were elucidated by extensive NMR and MS analysis, while the absolute configurations of the stereogenic carbons were established based on quantum-chemical electronic circular dichroism calculations or the modified Mosher's method. All the isolates were tested for α-glucosidase inhibitory activities. Compounds 1 and 3 displayed potent inhibitory activity against α-glucosidase with the IC50 values of 413.7 and 364.4 μM, respectively.

Instrument

J-815, P-1020

Keywords

alkaloid, circular dichroism, glucosidase