Neue germacranolide und andere inhaltsstoffe aus vertretern der subtribus gochnatiinae

The investigation of three further species belonging to the subtribe Gochnatiinae, tribe Mutisieae, afforded in addition to known compounds two new eudesmane derivatives and two new germacranolides, closely related to albicolide and salonitenolide. The structures are elucidated by spectroscopic methods and some chemical transformations. The chemotaxonomic aspects are discussed briefly.     

Neue labdan-derivate und andere inhaltsstoffe aus Relhania acerosa

The investigation of Relhania acerosa afforded, in addition to known compounds, three new labdane derivatives, two of which are esterified with succinic acid and one which has an anomalous carbon skeleton. Furthermore, several new aromatic compounds are isolated, which are most probably degradated thymol derivatives. The structures are elucidated by spectroscopic methods and by some chemical transformations. The stereochemistry of one of the new labdanes has been established by a partial synthesis. The chemotaxonomic situation is briefly discussed.     

Neue sesquiterpenlactone und thymol-derivate aus Inula-arten

The investigation of three Inula species affords, besides known compounds, two new sesquiterpene lactones and two new thymol derivatives. The chemotaxonomic situation in this genus is still very complicated.     

Neue cadinen-derivate und andere inhaltsstoffe aus Chromolaena-arten

The investigation of two further Chromolaena species afforded two new cadinene derivatives and a related structure with a degraded cadinene skeleton. Also present were two p-coumaric acid esters and a new flavanone. The structures were elucidated by spectroscopic methods. The chemotaxonomic situation is discussed briefly.     

Neue furanoeremophilane und andere sesquiterpene aus vertretern der gattung Euryops

Investigation of a further 27 Euryops species affords, besides known compounds, 55 new furanoeremophilanes together with several other compounds. The configuration of six furanoeremophilanes earlier given as 10β-H has to be changed to 10α-H. Furthermore 9 new eremophilenes were isolated; the configurations of four compounds of this type isolated before have had to be changed. One of the eremophilenes is esterified with 3-methylpent-3(E)-enoic acid, not found before in nature. Two hemiacetals, which are probable precursors of the furanoerephilanes, and a corresponding lactone are also present. Furthermore two benzylic esters, cis-caryophyllene, a bicyclo-germacrene derivative, and a new oplopanone derivative have been found. The structures are elucidated mainly by spectroscopic methods together with some chemical transformations. From the chemotaxonomic viewpoint, the high concentration of very variable furanoeremophilanes may be important. The proposed differentiation into sections however can not be clearly correlated with the chemical constituents, though some taxonomic conclusions seem to be supported by the chemical evidence.     

Neue sesquiterpenlactone und nerolidol-derivate aus Ursinia-arten

The aerial parts of U. anethoides afforded, in addition to new nerolidol derivatives, a new germacranolide. The structure could only be elucidated by formation of the corresponding pyrazoline derivative and by comparison of the ¹H NMR data with those of similar pyrazolines. The aerial parts of U. alpina also contain a new nerolidol derivative and, in addition to the known 9β-hydroxycostunolide, a new eudesmanolide. The roots of all species contain furanosesquiterpenes, which are also present in related genera.     

Neue geranyl-cumarin-derivate und weitere inhaltsstoffe aus der tribus mutisieae

The investigation of further species of the tribe Mutisieae afforded in addition to already known compounds a new sesquiterpene derived from bisabolene, a new chromene, two benzofurans and two geranyl derivatives of typical coumarins. The chemotaxonomic importance of these compounds is discussed briefly.     

Neue sesquiterpene und norditerpene aus vertretern der gattung Libanothamnus

The aerial parts of L. granatesianus afforded in addition to known compounds two nor- ent-kaurenes, while those of L. occultus yielded in addition to several diterpenes, two new dialdehydes derived from silinene. The chemotaxonomic situation is discussed briefly.     

Neue diterpene und neue dihydrochalkon-derivate sowie weitere inhaltsstoffe aus Helichrysum-arten

The investigation of 25 further Helichrysum species afforded in addition to known compounds a new diterpene, an oxo-geranyllinalol, a second one, most probably a cembrene derivative, and three dihydrochalkone derivatives. The distribution of the constituents in South African Helichrysum species is discussed briefly.     

Cis-Kolaveninsäure und weitere inhaltsstoffe aus vertretern der tribus eupatorieae

The investigation of further species of the tribe Eupatorieae afforded in addition to already known compounds two new diterpenic acids, three euparine derivatives, two chromenes and two guaianolides closely related to known structures. The results show again the complexity of the tribe; however, some chemotaxonomic lines are visible.     

Neue norkauren- und thymol-derivate aus Athrixia-arten

Investigation of seven Athrixia species affords besides known compounds four new norkaurene derivatives and six thymol derivatives. The structures are elucidated mainly by spectroscopic methods, together with some chemical transformations. Due to nonplanarity of the chromophoric system, one of the compounds shows some surprising spectroscopic data. The chemotaxonomic aspects of these findings are discussed briefly.     

Neue C10-säureamide,furanoeremophilane und andere inhaltsstoffe aus bolivianischen Senecio-arten

The investigation of seven Bolivian Senecio species afforded in addition to known compounds five new furanoeremophilanes, two C₁₀-amides, a new isoeugenol ester and the isomer of pterophorin. The structures are elucidated mainly by spectroscopic methods. While most of the new compounds are closely related to those isolated before from Senecio species, four of them are unusual. Another is a new type of a furanoeremophilane; its biogenesis however, can be explained easily from known types.     

Neue melampolide und cis,cis-germacranolide aus vertretern der subtribus melampodiinae

The investigation of four South American species of the tribe Heliantheae afforded in addition to known compounds 14 new sesquiterpene lactones, mostly belonging to the melampolides, but four being further examples of cis,cis-germacranolides. The stereochemistry is established by intensive ¹H-NMR studies and some chemical transformations. Some of the new lactones were only obtainable as inseparable mixtures of 2-methylbutyric and isovaleric esters. Furthermore a new acetylenic aldehyde was isolated. The chemotaxonomic situation is discussed especially with regard to the position of the genus Smallanthus.     

Ein neuer sesquiterpenalkohol und andere inhaltsstoffe aus Doronicum pardalianches

A thorough investigation of the roots and the aerial parts of Doronicum pardalianches afforded numerous known compounds, mainly thymol and tremetone derivatives, and a new p-hydroxyacetophenone derivative. Furthermore a new sesquiterpene alcohol with an unusual carbon skeleton is present. Intensive NMR studies show that the alcohol most probably is of a new skeletal type which, however, is related to that of mexicanin D.     

Neue furanoeremophilane und weitere inhaltsstoffe aus südafrikanischen Senecio-arten

The investigation of further 27 South African and a few other Senecio species afforded in addition to known compounds 18 new furanoeremophilanes, most of them being cacalol derivatives, two new lactones, a new eudesmane derivative and four acyl pyrrole derivatives. The structures are elucidated by spectroscopic methods mainly. The chemical results on more than 140 species now available indicate much of chemotaxonomic interest. Together with the chemical data on related genera, the taxonomic situation of the subtribe Senecioninae is discussed in connection with the proposed new classification. The chemical data are in good agreement with this new arrangement.     

Weitere bisabolen-derivate und andere inhaltsstoffe aus südafrikanischen Senecio-arten

The investigation of additional Senecio species afforded five new bisabolene derivatives, two acetylenic compounds and two aromatic compounds,