GC/MS investigations of the minor constituents of Piper guineense stem.

Chemical investigations by GC/MS-analysis of stem extracts of Piper guineense resulted in the detection and identification of thirty-nine new constituents of the stem, apart from previously isolated constituents. These are isobutyl, pyrrolidyl and piperidyl amide alkaloids. Fifteen new natural products have been identified. Four of these natural products have been designated iyeremide A and B (these are pyrrolidine and piperidine analogues of pellitorine) and cycloguineense A and B, which are also piperidine analogues of cyclostachine A and B. There is a need to confirm the structures of some of these new constituents by synthesis. Apart from these amide alkaloids, many volatile oil components-monoterpenes, sesquiterpenes, terpenoids, lignans and sterols--were detected.