Antioxidative Constituents from the Aerial Part of Piper elongatum VAHL.

Abstract

Six aromatic compounds, asebogenin (1), 2',6'-dihydroxy-4'-methoxydihydrochalcone (2), 3-geranyl-4-methoxy-benzoic acid (3), 3-geranyl-4-hydroxybenzoic acid (4), nervogenic acid (5) and 2,2-dimethyl-6-carboxyl-8-prenyl-chromene (6) were isolated from the methanol extract of the aerial part of Piper elongatum VAHL., whose leaves are used as a folk medicine in South America. The structures of 1-6 were elucidated by MS, 1H-NMR and 13C-NMR spectroscopies, and chemical evidence. Among these compounds, 1 showed stronger antioxidative activity than that of α-tocopherol, and 4 and 5 exhibited higher activity than that of t-butyl-4-hydroxyanisole (BHA) using the ferric thiocyanate method.