Anti-inflammatory cyclopentene derivatives from the inner bark of Tabebuia avellanedae.

Six new cyclopentenyl esters, avellaneine A-F (1-4, 7, 8), two new cyclopentyl esters, avellaneine G, H (9, 10), along with two known cyclopentenyl esters were obtained from water extract of the inner bark of Tabebuia avellanedae Lorentz ex Griseb. The chemical structures of the new compounds were elucidated by spectroscopic techniques. The anti-inflammatory effects of these compounds were determined on LPS-stimulated RAW 264.7 cell line. Some of the tested compounds (2, 3, 4, 6, 7) reduced the NO production in a dose-dependent manner, while 6 and 7 decreased PGE2 production in a dose-dependent manner, without altering cell viability. Data presented in this research indicated that Tabebuia avellanedae's ethnopharmacological action of treating inflammatory diseases was based on the constituents which exert a significant anti-inflammatory effect on inflammatory responses.