Phenylpropionamides, Piperidine, and Phenolic Derivatives from the Fruit of Ailanthus altissima

Four novel compoundstwo phenylpropionamides, one piperidine, and one phenolic derivativeswere isolated and identified from the fruit of a medicinal plant, Ailanthus altissima (Mill.) Swingle (Simaroubaceae), together with one known phenylpropionamide, 13 known phenols, and 10 flavonoids. The structures of the new compounds were elucidated as 2-hydroxy-N-[(2-O--d-glucopyranosyl)phenyl]propionamide (1), 2-hydroxy-N-[(2-O--d-glucopyranosyl-(16)--d-glucopyranosyl)phenyl]propionamide (2), 2-carboxyl-piperidine-4-acetic acid methyl ester (4), and 4-hydroxyphenyl-1-O-[6-(hydrogen-3-hydroxy-3-methylpentanedioate)]--d-glucopyranoside (5) based on spectroscopic analysis. All the isolated compounds were evaluated for their inhibitory activity against Tobacco mosaic virus (TMV) using the leaf-disc method. Among the compounds isolated, arbutin (6), -d-glucopyranosyl-(16)-arbutin (7), 4-methoxyphenylacetic acid (10), and corilagin (18) showed moderate inhibition against TMV with IC50 values of 0.49, 0.51, 0.27, and 0.45 mM, respectively.