Brevipedicelones D and E, Two C–O–C Flavonoid Dimmers from the Leaves of Garcinia brevipedicellata and Anti-onchocercal Activity

ABSTRACT: A novel isoflavone–chromone flavonoid C–O–C dimmer, brevipedicelone D (1), along with one new C–O–C biflavonoid derivative, brevipedicelone E (2), were isolated from the ethyl acetate extract of the leaves of Garcinia brevipedicellata, a medicinal plant used in folk medicine in parts of Cameroon. Their structures were elucidated by extensive spectroscopic techniques, including 1D- and 2D- NMR, MS experiments, as well as comparing their spectral data with those of known analogues. Anti-onchocercal screening of 1 showed moderate inhibition of adult worm motility of Onchocerca ochengi by 60% at the highest concentration (20 µg/mL) and inhibited motility of both the juvenile worms of O. ochengi and Loa loa by 90% at this same concentration. GRAPHICAL ABSTRACT: [Image: see text] ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13659-018-0191-9) contains supplementary material, which is available to authorized users.