A New Aromatic Amide from the Roots of Zanthoxylum tessmannii (Rutaceae).

Phytochemical investigation of the methanolic extract of the roots of Zanthoxylum tessmannii Zepernick and Timler (Rutaceae) led to the isolation and characterization of one new aromatic amide named tessmamide (1) along with twelve known compounds, N-benzoyltyramine methyl ether (2), 7,8,9-trimethoxycoumarin (3), 7,8-dimethoxycoumarin (4), integrifoliodiol (5), robustin (6), skimmianine (7), lupeol (8), lupenone (9), a mixture of stigmasterol and ß-sitosterol, and a mixture of their glucosides. The structures of all compounds were determined by comprehensive spectroscopic analyses (1D- and 2D-NMR, EI-MS, and ESI-MS) and comparison with known analogs. The determination of the radical scavenging activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay gave moderate antioxidant values for the crude extracts of the roots of Zanthoxylum tessmannii (IC50 0.8 mg/mL), tessmamide (1; IC50 31.8 µm), and 7,8,9-trimethoxycoumarin (3; IC50 29.3 µm), compared to the standard ascorbic acid (IC50 11.6 µm).