Twenty-three compounds, a novel neolignan nine known neolignans and 13 known alkaloids, were isolated from a methanol extract of stems of Piper argyrophylum. The structure of the new neolignan, 4-(2-piperonyl-2-hydroxy-1-methylethyl-2,5-dimethoxy-2(2-propenyl)-3,5-cyclohexadien-1-one, was elucidated on the basis of its spectral data, whereas the known neolignans and alkaloids were identified by comparsion of their spectral data with those reported earlier. Ail compounds are new from P. argyrophylum. Copyright (C) 1996 Elsevier Science Ltd