Phenylpropanoid amides from Alisma orientalis and their protective effects against H2O2-induced damage in SH-SY5Y cells

Abstract

Five new phenylpropanoid amides, including N-trans-feruloyl-N′-cis-feruloyl-cadaverine (1), N,N′-trans-diferuloyl-3-oxo-cadaverine (2), N-trans-feruloyl-N′-cis-feruloyl-3-hydroxy-cadaverine (3), N,N′-cis-diferuloyl-3-hydroxy-cadaverine (4), N-trans-p-coumaroyl-N′-trans-feruloyl-3-hydroxy-cadaverine (5), were isolated from Alisma orientalis together with four known analogues. Their structural elucidations were conducted by using 1D and 2D NMR and HRESIMS spectroscopic analyses. The isolated compounds were assayed for their inhibitory activities against HCE-2, anti-oxidant effects, and their protective effects on H2O2-induced damage in human dopaminergic neuroblastoma cells (SH-SY5Y). Compounds 3, 6, and 7 displayed moderate anti-oxidant activities with IC50 values in the range of 36.9–40.7μM. Compound 5 showed significant protective activity, while compounds 1, 2, 4, 7, and 8 showed moderate protective activities.