A New Prenylated Flavanone from Derris trifoliata Lour.

Abstract

A new flavanone, 4′,5,7-trihydroxy-6,8-di-(2-hydroxy-3-methylbut-3-enyl)- flavanone, was isolated from the aerial parts of Derris trifoliate, together with eleven known compounds: rotenone, tephrosin, 12a-hydroxyrotenone, deguelin, 6a,12a-dehydro-rotenone, dehydrodeguelin, 7a-O-methyldeguelol, 7a-O-methylelliptonol, 5,7,3',4'-tetra-hydroxy-6,8-diprenylisoflavone, daidzein and 4'-hydroxy-7-methoxyflavanone. 7a-O-Methylelliptonol was isolated for the first time from the genus Derris. Their structures were characterized on the basis of spectral data. Eight of the isolated compounds were found to be significantly toxic to brine shrimp (LC50 range 0.06–9.95 μg/mL). The new compound showed weak toxicity (LC50 = 211.31 μg/mL).

Rotenoid Derivatives from Derris Trifoliata with Nitric Oxide Production Inhibitory Activity

“…The IR spectrum showed absorption bands due to hydroxy and conjugated carbonyl groups. The UV spectrum was similar to that of 7a-Omethylelliptonol (4) [8], which we also isolated from the same plant. The 1 H NMR spectral data of 2 (Table 1) showed signals corresponding to two methylene signals at  4.24 (2H, m, H-6) and 1.98, 2.51 (each 1H, H-6a), a hydroxy signal at  5.00, three singlet signals of methoxy groups at  3.71, 3.86, and 3.98, two singlet signals of aromatic protons at  6.52 (1H, s, H-1) and 6.48 (1H, s, H-4), two ortho-coupled doublets at  7.05 (1H, d, J = 8.4 Hz, H-10) and 6.85 (1H, d, J = 8.4 Hz, H-11), and a 1,2-disubstituted furan moiety at  6.93 (1H, d, J = 2.2 Hz, H-3') and  7.59 (1H, d, J = 2.2 Hz, H-2').…”