Norquandrangularic acid D, a new trinorcycloartane isolated from the leaves of Combretum quadrangulare

Abstract

Phytochemical investigation on the leaves of Combretum quadrangulare growing in Vietnam afforded a new trinorcycloartane triterpenoid, norquandrangularic acid D (1), along with three known compounds, betulinic acid (2), luteolin (3), and apigenin (4). Their structures were elucidated using spectroscopic methods and comparison was made with reports in the literature. Compounds 1 and 3 were evaluated for α-glucosidase inhibition. Compound 3 showed significant activity, with an IC₅₀ value of 11.39 µM, (acarbose, used as a positive control, had an IC₅₀ of 367 µM).

Keywords:

• Combretaceae; Combretum quadrangulare
• norquandrangularic acid D
• trinorcycloartane triterpenoid; α-glucosidase inhibition

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research is funded by Vietnam Ministry of Education and Training grant #B2021-SPS-03-HH). The authors also gratefully acknowledge the chemical support from Thammasat University Research Unit in Natural Products Chemistry and Bioactivities.