New furanosesquiterpenes from Eumorphia species

Eumorphia sericea and E. prostata contained several new furanosesquiterpenes and a new triterpene aldehyde. Structures were elucidated mainly by spectroscopic methods and by some chemical reactions. Structures of three compounds however could not be established with certainty and are partially based on biogenetic considerations. Gymnopentzia bifurcata also contained known furanosesquiterpenes. The number of South African genera from the tribe Anthemideae, where these furanosesquiterpenes are characteristic, has now increased to eight. The importance of these observations for the botanical position of these genera is still not clear.     

Guaianolides and furanosesquiterpenes from Ursinia nana

The investigation of Ursinia nana afforded in addition to the typical known furanosesquiterpenes two new compounds, probably both derived from the     

Enantio-eudesmane sesquiterpenes from it Verbesina rupestris

The leaves and stems of Verbesina rupestris contain enantio-eudesmane sesquiterpenes, isolated as esters of cinnamic acid. This finding supports th     

Furanoeremophilanes from Lopholaena species

Three additional Lopholaena species afforded several furanoeremophilanes, two of them not reported previously.     

Eudesmanolides from Artemisia judaica

The aerial parts of Artemisia judaica afforded in addition to known compounds a hydroperoxide corresponding to vulgarin as well as an isomer of the latter. The configurations of these lactones have been established by NOE difference spectroscopy.     

Sesquiterpene acids from Dittrichia viscosa

Dittrichia viscosa afforded in addition to compounds reported previously, ilicic acid and two new sesquiterpene acids. The structures of the new compounds were established by chemical and spectral methods.     

Seco-helenanolides from Dugaldia integrifolia

The aerial parts of Dugaldia integrifolia afforded, in addition to acetylhymenograndin, floribundin, hymenoxon and isotelekin, three new seco-helenanolides and two derivatives of silphinene, one being isolated previously from Dugaldia hoopesii     

Further cadinene derivatives from Heterotheca latifolia

A reinvestigation of the aerial parts of Heterotheca latifolia afforded four new cadinene derivatives.     

Two new eudesmane cinnamates from Verbesina sordescens

From Verbesina sordescens two new eudesmane cinnamates were isolated.     

Sesquiterpenes from Kleinia species

The investigation of four Kleinia species afforded, in addition to known compounds, seven new germacrane and three oplopane derivatives, all highly oxygenated. This kind of sesquiterpene seems to be characteristic of the genus Kleinia and related succulent species, and its tentative grouping is discussed.     

Further silphinene derivatives from Cineraria geifolia var. glabra

A reinvestigation of the sesquiterpenes from the aerial parts of Cineraria geifolia var. glabra afforded eight new silphinene derivatives. One of these compounds had been isolated previously but its structure had not been elucidated with certainty. The stereochemistry of a corresponding isovalerate from Callilepis salicifolia has to be revised.     

Two tricyclic sesquiterpenes from Senecio anteuphorbium and Ursinia nana

The aerial parts of Senecio anteuphorbium afforded a new sesquiterpene diester, its structure being elucidated by extensive NMR investigations of t     

Caryophyllane derivatives from Pulicaria scabra

The investigation of Pulicaria scabra afforded in addition to known compounds seven new caryophyllane derivatives, three of them etherified with a caryophyllane derivative and one esterified with a caryophyllane derived alcohol. The structures were elucidated by high field ¹H NMR spectroscopy. The chemistry of this species is similar to that of P. dysenterica but differs from that of the other genera of the subtribe Inulinae.     

Furanoeremophilanes from Senecio smithii

The investigation of Senecio smithii afforded 17 furanoeremophilanes, six of them being isolated for the first time. Furthermore, two new bisabolon     

Cadina-4,11-diene from Viguiera oblongifolia

Viguiera oblongifolia afforded two known furanoheliangolides and a new cadinane derivative whose structure was established by spectroscopic methods. From V. lanceolata 17,18-dihydrobudlein A was isolated.     

Sesquiterpenes from Perezia carpholepis

The previously unknown curcuquinol monoisovalerate and the known sesquiterpenes cyperene, cyperone, parvifoline, perezone, and α- and β-pipitzol were found in the roots of Perezia carpholepis. The structure of the new sesquiterpene was deduced from spectral data and by transformation into curcuquinone. Parvifoline and its derived acetate, previously thought to be oily materials, were characterized as crystalline compounds.     

New cadinene derivatives from Heterotheca latifolia

Heterotheca latifolia afforded several new acids all derived from cadinane.