NEW SESQUITERPENE LACTONES, GERANYLLINALOL DERIVATIVES AND OTHER CONSTITUENTS FROM GEIGERIA SPECIES

Article abstract of DOI:10.1016/S0031-9422(82)85040-1

The investigation of three Geigeria species and five subspecies afforded, in addition to known compounds, the following 32 new compounds: two geigeranolides with a new carbon skeleton, two xanthanolides, five guaianolides, three pseudoguaianolides, a sesquiterpene related to ivaxillarin, a nerolidol derivative, 15 geranyllinalol derivatives, two thiophene acetylenes and a dimeric coniferyl isobutyrate.The structures and the stereochemistry of the new compounds were elucidated by spectroscopic methods and a few chemical transformations.Chemotaxonomic aspects and relationships of the compounds are discussed. - Key Word Index: Geigeria aspera; G. brevifolia; G. burkei subsp.; Compositae; Inuleae; sesquiterpene lactones; guaianolides; pseudoguaianolides; xanthanolides; geigeranolides; diterpenes; geranyllinalol derivatives; thiophene acetylenes; nerolidol derivative; new carbon skeleton.