Isobutylamides and a new methylbutylamide from Piper sarmentosum.

A homologous series of six 2 E,4 E-diene-isobutylamides and a new N-2'-methylbutyl-2 E,4 E-decadieneamide were isolated from the N-hexane extract of the aerial parts of PIPER SARMENTOSUM. While the crude extract was found to possess cyclooxygenase-1 (COX-1) and 5-lipoxygenase (5-LO) inhibitory activity (COX-1 IC (50) = 19 microg/ml; 5-LO IC (50) = 10 microg/ml), the isolated compounds showed only weak effects in both test systems.