Isolation and structure–activity relationship studies of jacaranones: Anti-inflammatory quinoids from the Cuban endemic plant Jacaranda arborea (Bignoniaceae)

Article abstract of DOI:10.1016/j.tetlet.2020.152005

The Cuban endemic plant Jacaranda arborea (Bignoniaceae) has been traditionally used in folk medicine as an acaricide and for acne treatment. Two known quinoids, methyl (1-hydroxy-4-oxocyclohexa-2,5-dien-1-yl)acetate (jacaranone) (1) and its ethyl ester 2 were isolated from this species as anti-inflammatory substances. Compound 1 prominently inhibited the production of TNF-α in both LPS-treated macrophages and mice, with low toxicity. Structure-activity relationship studies revealed that the high electrophilicity of 1 as a Michael acceptor played an important role in these effects. Unlike in previous studies, such as those on antitumor, anti-oxidant, and anti-malarial activities, ester derivatives of 1 retained their potent anti-inflammatory activity. Our results suggest that jacaranones may target specific biomacromolecule(s) at lower concentrations than hitherto expected to exhibit potent activities.