Neue phloroglucin-derivate aus Leontonyx-arten sowie weitere verbindungen aus vertretern der tribus inuleae

The investigation of several South African species of the tribe Inuleae afforded in addition to known compounds 16 new constituents. From Leontonyx a group of 9 new phloroglucinol derivatives, from Stoebe species two new p-hydroxyacetophenone, two thymol and two coumaric acid derivatives and from Relhania a new euparine-derivative were isolated. The structures are elucidated mainly by spectroscopic methods. The chemotaxonomic aspects are discussed briefly. The phloroglucinol derivatives, which in part are derived from geraniol, seem to be especially characteristic.     

Neue labdan- und pimaren-derivate aus Palafoxia rosea

The investigation ofPalafoxia rosea afforded in addition to known compounds five new labdane derivatives and five pimarene derivatives. The structures are elucidated by spectroscopic methods and some chemical transformations. The chemotaxonomic situation of the genus is 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 sesquiterpene,triterpene, flavanone und andere aromatische verbindungen aus Flourensia heterolepis

The investigation of a further Flourensia species afforded in addition to already known compounds 12 new sesquiterpene acids isolated as their methyl esters, a new eudesmane diol, four lupane derivatives and two flavanones, two cinnamic acid derivatives, also isolated as methyl esters and a ketone. The structures are elucidated mainly by spectroscopic methods and by some chemical transformations. Several of the compounds isolated are more or less similar to those isolated from other Flourensia species; the considerable amounts of eudesmanes, however, are unusual. The overall picture of the genus is still relatively uniform. Close relationships to Helianthella are obvious, while to Helianthus, placed in the same subtribe, no clear relations are visible.     

Neue sesquiterpenlactone und andere inhaltsstoffe aus vertretern der Eupatorium-gruppe

The investigation of twelve further species of the Eupatorium complex affords four new germacrolides and seven guaianolides together with new thymol and p-hydroxyacetophenone derivatives. The structures of these compounds have been elucidated by spectroscopic methods. Chemotaxonomic aspects of these findings are briefly discussed.     

Neuartige cumarin-derivative aus Ethulia conyzoides

The aereal parts of Ethulia conyzoides contain two new coumarins which are related to those of Erlangea and Bothriocline. They are, however, condensed with a terpene. The structures have been elucidated by spectroscopic methods.     

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.     

Eudesmane derivatives from Verbesina species

The investigation of seven Verbesina species afforded, in addition to known compounds, several new eudesmane and germacrane derivatives, all bearing a cinnamate or derivatives as residue. Furthermore, a new bisabolene aldehyde and two acetophenone derivatives were isolated. The structures were elucidated mainly by spectroscopic methods and some chemical transformations. The chemotaxonomic situation is discussed briefly.     

Neue ent-atisiren- und ent-kaurensäure-derivate aus Helianthus-arten

The investigation of four Helianthus species afforded, in addition to known compounds, four new atisirenic acid derivatives, a new ent-kaurenic acid derivative, three new labdane derivatives and an unknown C₁₅-acetylenic compound. The structures of the diterpenes were elucidated by intensive NMR studies and some chemical transformations. An unusual fragmentation in the mass spectra of the atisirenes is discussed briefly.     

Neue germacranolide aus Calea urticifolia

The investigation of Calea urticifolia afforded eight new germacranolides. While five are heliangolides, three are of a new type and have some unusual structural features. The structures are elucidated by extensive ¹H-NMR studies and some chemical transformations. In addition, a new isoeugenol and an unusual phloroglucinol derivative were isolated; the structure of the latter could only be established after some chemical transformations. Other Calea species contain typical C₁₇ acetylenes only, also present in other species of the subtribe Galinsoginae. So far, the results on Calea indicate that the genus is chemically heterogenous.     

Neue α-santalen- und labdan-derivate aus Ayapana amygdalina

While the roots of Ayapana amygdalina contain typical euparine derivatives, the aerial parts afforded in addition to known compounds two new α-santalene derivatives as well as twelve new labdane derivatives with a partly unusual oxidation pattern, two being norditerpenes. Furthermore, a new bisabolene isomer is present. The structures were elucidated by spectroscopic methods and a few chemical transformations. The chemotaxonomy is discussed briefly.     

Neue phloroglucin-derivate aus Helichrysum natalitium und Helichrysum bellum

Helichrysum natalitium afforded four new phloroglucinol derivatives, while from H. bellum two further compounds of this type have been isolated; H. platypterum yielded two known derivatives. The new structures were elucidated by spectroscopic methods and some chemical transformations. The chemotaxonomical situation is briefly discussed.     

Neue kaurensäure-derivate und germacranolide aus Montanoa pteropoda

The investigation of Montanoa pteropoda afforded in addition to known kaurene-derivatives three new ones and three germacranolides, which most probably have the structures as shown. The structures are elucidated by extensive ¹H-NMR studies and some chemical transformation. The chemotaxonomical situation is discussed briefly.     

Neuen kaurensaure-derivate aus Wedelia-arten

The investigation of three South American Wedelia species affords besides known acetylenes several new kaurenic acid derivatives, which have been isolated as their methyl esters. Their structures are elucidated by spectroscopic methods. Chemotaxonomic aspects are discussed.     

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.     

New labdane derivatives and further constituents of Brickellia species

The investigation of several Brickellia species and two further related species afford besides known compounds four new labdane derivatives, a new acetylenic carbinol and a new dihydrobenzofuran derivative. The structures have been elucidated by spectroscopic methods. The chemotaxonomic aspects are discussed briefly.     

Neue labdan-derivate aus Chrysothamnus nauseusus

The South American Chrysothamnus species afforded in addition to known compounds six new labdanetype acids, a bisabolene and a germacrene derivative as well as a new flavanone. The structures were elucidated by spectroscopic methods.     

Neue germacren-derivate aus Senecio-arten

From the succulent Senecio species, S. cylindricus, eight new germacrene derivatives were isolated, while S. erosus afforded two new furanoeremophilones. Six further species only contain known compounds. The chemotaxonomic importance of these findings are briefly discussed.     

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 cadinan-derivate aus Heterotheca subaxillaris

The investigation of some Heterotheca species afforded three new cadinane angelicates, in addition to several known compounds. The structures are elucidated by spectroscopic methods. The chemotaxonomic situation is discussed briefly.