Polyphenols and alkaloids from Piper species

Thirty eight compounds of different types have been isolated from twelve Piper species. The ether extract of the leaves of P. aduncum yielded eleven compounds, out of which 2,6-dimethoxy-4-(2-propenyl)phenol was isolated for the first time from the genus Piper and 2-acetoxy-1,3-dimethoxy-5-(2-propenyl)benzene is a new compound. The petrol extract of the stems and leaves of P. attenuatum furnished a novel long chain alcohol, 14-benzo[1,3]dioxol-5-yl-tetradecan-2-ol From P. betle, beta-sitosteryl palmitate was isolated for the first time from the genus Piper. A novel amide, 3-(3,4-dimethoxyphenyl)propanoyl pyrrole has been obtained from P. brachystachyum. Nerolidol was isolated for the first time from P. falconeri. From the methanol extract of the stems and leaves of P. khasiana, piperlonguminine, piperine, apigenin dimethyl ether and beta-sitosterol were obtained. Retrofractamide A was obtained for the first time from P. longum; the structure of (+)-asarinin, isolated from P. longum, was confirmed by X-ray crystallographic studies. Retrofractamide A, apigenin dimethyl ether, tetratriacontanol and tectochrysin were isolated from P. manii. P. pedicellosum furnished beta-sitosterol, pellitorine, piperlonguminine, cepharadione A and furacridone, the last compound being isolated for the first time from the genus Piper. (C) 1998 Elsevier Science Ltd. All rights reserved.