Neue cadinen- und norcadinen-derivate aus Heterotheca grandiflora

The aerial parts of Heterotheca grandiflora afforded, in addition to known compounds, nine new cadinene and four norcadinene derivatives, which probably are formed by decarboxylation of 2-methoxycalamenen-14-acid or related acids. The structures were elucidated by spectroscopic methods and a few chemical transformations.     

Germacrene derivatives and other sesquiterpenes from Senecio species and Lordhowea insularis

From Senecio galpinii six new highly oxygenated germacrene derivatives were isolated, while S. coronatus afforded in addition to known cacalol derivatives two new ones. This species also contained a rare tricyclic sesquiterpene angelate, so far only isolated from one species. From the aerial parts of S. pleistocephalus an angelate derived from cadinene was isolated, while Lordhowea insularis (Benth.) B. Nord. afforded farnesyl angelate, which was reported previously. The structures were elucidicated mainly by high field ¹H NMR spectroscopy.     

Three cadinene derivatives and a prostaglandin-like acid from Chromolaena species

An investigation of the aerial parts of Chromolaena chasleae afforded a prostaglandin-like acid, whose structure followed from the ¹H NMR spectral data and from the reaction with periodate, which afforded a hemiacetal. From a new Chromolaena species, three novel cadinene derivatives were isolated, which were closely related to those isolated previously from this genus.     

Further cadinene derivatives from Heterotheca latifolia

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

Cadinenes and other metabolites from Verbesina sphaerocephala A. Gray

The phytochemical study of the aerial parts of Verbesina sphaerocephala A. Gray afforded six sesquiterpene lactones of cadinene type, five of them described for the first time, along with known phenyl propanoids, terpenoids, and phenolic compounds. Structures on new compounds were elucidated by spectroscopic techniques including CD and X-ray analyses, and known compounds were identified by comparing their spectral data with those previously reported. Cadinene-like sesquiterpene lactones could be characteristic metabolites of V. sphaerocephala.     

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 acetylenverbindungen aus Leucanthemum-arten und revision der struktur eines germacranolids

The investigation of three Leucanthemum species afforded, in addition to known compounds, two new C₁₇-acetylenes, a new isovalerate, two phenolic acetylenes, a C₁₂-isobutylamide and a new farnesol derivative. Chrysanthemum ferulaceum contains deacetyllaurenobiolide (spiciformin) which is identical with a lactone from Inula britannica previously assumed to be a cis, cis-germacranolide.     

Neuartige sesquiterpenlactone und neue acetylenverbingen aus Athanasia-arten

The investigation of two further South African Athanasia-species afforded, in addition to known compounds, sixteen new ones, ten guaianolides, an eudesmanolide, three sesquiterpenes, a new enediynene and a phenylpropane derivative. The structures were elucidated by extensive NMR-studies. Three of the lactones are very unusual in having an endoperoxide bridge; their structures, however, were elucidated only indirectly. These further chemical results on Athanasia again add support to the idea that these species might be better placed in the genus Pentzia.     

Einige neue furanoeremophilane aus Senecio-Arten

The investigation of two varieties of the South African S. hypochoerideus affords, besides known compounds, six new furanoeremophilanes and a pimarene-derivative. By contrast, S. greyi has yielded two further new furanoeremophilanes and a new eremophilene. These structures are elucidated mainly by spectroscopic methods. Chemotaxonomic aspects are briefly discussed.     

Weitere hirsutinolide aus Vernonia-arten

The investigation of two Bolivian Vernonia species afforded, in addition to known compounds, five further enollactones of the hirsutinolide type and a new hydroxyzaluzanine. The structures were elucidated by intensive ¹H NMR studies and some chemical transformations. The results show again that the hirsutinolides are probably of chemotaxonomic importance in the large genus Vernonia.     

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 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 diterpene aus Gnaphalium-arten

The investigation of Gnaphalium undulatum afforded two new labdane derivatives, one having a new carbon skeleton, and a new flavonol. Furthermore, an unknown diterpene lactose is present; its structure, however, could not be elucidated. The only American species investigated contains the trans-isomer of the precursor of the acetylenic chloroenol ether, which is widespread in Gnaphalium and in related genera. The chemotaxonomic situation is discussed briefly.     

Eremophilane derivatives from Senecio species

The investigation of two further Senecio species afforded two new furanoeremophilanes, four eremophilanolides and a new hydroxyeremophilane. The structures of two furanoeremophilane, isolated before, have been revised.     

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.     

The leaf oil terpene composition of Juniperus occidentalis

The chemical composition of the volatile oil of 10 trees each of two Oregon populations of the western juniper was determined by a computerized GC-MS method. The identity of the major components, sabinene, α-pinene, α- and γ-terpinene, p-cymene, limonene, terpinen-4-ol and bornyl acetate was confirmed. In addition, tricyclene, α-thujene, camphene, β-pinene, α- and β-phellandrene, car-3-ene, trans-ocimene, linalool oxide, terpinolene, trans-sabinene hydrate, camphor, camphene hydrate, borneol, α-terpineol, p-cymenol, methyl citronellate, citronellyl acetate, carvacrol, cuminic aldehyde, β-bourbonene, several cadinene and cadinol isomers, elemol, γ-, β- and α-eudesmol, and manoyl oxide were identified. Santene, citronellol, and aromatic ethers of the safrole-eugenol type were not found. Tree-to-tree variability of the relative percentages of these terpenes was fairly large and chemosystematic implications 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.     

Five diterpenes and other constituents from nine Baccharis species

The investigation of nine Baccharis species afforded, in addition to known compounds, three new clerodane derivatives related to bacchotricuneatin B, two ent-labdane derivatives, two 3-acetoxyflavanones, a benzofuran derivative and a chromene. The overall picture of the chemistry of this large genus is still not very clear.     

Diterpenes and tetranorditerpenes from Acritopappus species

The investigation of four Acritopappus species afforded twenty-three new diterpenes of the labdane or kolavane type and three tetranorditerpenes as well as two new benzofuran derivatives and a hydroxybicyclogermacrene. The structures were elucidated by spectroscopic methods and by some chemical transformations. Though the absolute configuration were not established in all cases, most probably all diterpenes were ent-labdanes or kolavanes (clerodanes). The chemotaxonomic importance of this investigation is discussed briefly.     

Über einen neuen sesquiterpentyp aus Senecio oxyriifolius

The roots of Senecio oxyriifolius contain a new tricyclic sesquiterpene with a new carbon skeleton, probably formed from α-humulene, and two bisabolene derivatives. The structures were elucidated by spectroscopic methods and some chemical transformations.