Abstract
Continuation of the phytochemical investigation of the aerial parts ofTephrosia purpureasubsp.dunensisresulted in the isolation and structural elucidation of a new prenylated flavonoid demeapollinin (1), glabratephrinol (2) and a mixture (3) of tephroapollin G (3a) andepi-tephroapollin G (3b). The neuroprotective activity of compounds (1-3) besides the previously isolated compounds; dunensin (4), pseudosemiglabrin (6), glabratephrin (7), apollinin (5), kampferol 3, 7-O-alpha-L-dirhamnoside (8) and quercetin 3, 7-O-alpha-L-dirhamnoside (9) was examined. Molecular docking, acetylcholine esterase inhibitory assay and protection against both H(2)O(2)and induced neurotoxicity were used to evaluate their neuroprotective effect. Compound2showed the highest acetylcholine esterase inhibitory activity (IC(50)4.31 +/- 0.75 mu M) compared to galantamine (IC(50)1.64 +/- 0.32 mu M), compounds4and3exhibited potent protective effect against induced neurotoxicity (IC(50)7.70 +/- 5.23 and 10.91 +/- 6.27 mu M, respectively) compared to standard epigallocatechin gallate (IC(50)18.36 +/- 6.22 mu M).