Neue sesquiterpene aus Artemisia koidzumii

The roots of A. koidzumii afforded, in addition to known compounds, a new sesquiterpene with an anomalous carbon skeleton, while the aerial parts yielded a new nerolidol and a new farnesol derivative. The structures were elucidated by spectroscopic methods and some chemical transformations.     

A daucanolide further farnesene derivatives from Ageratum fastigiatum

A reinvestigation of Ageratum fastigiatum afforded, in addition to known compounds, several new farnesene derivatives including some tetrahydropyrane derivatives. Furthermore a sesquiterpene lactone derived from daucane and a minor derivative of the ent-labdanes isolated previously were isolated. The structures were elucidated by spectroscopic methods.     

Sesquiterpenes and a dimeric spiroketone from Cineraria fruticulorum

The aerial parts of Cineraria fruticulorum afforded in addition to known compounds three spathulenol derivatives, a hydroxymyrtenol and an oxo-humulene, while the roots gave in addition to known compounds a further humulene derivative, three cinalbicol derivatives, a sesquiterpene with a spirodienone moiety and its dimer. From C. parvifolia only known compounds were isolated which, however, confirmed previous results on this genus. The structures were elucidated by spectroscopic methods and a few chemical transformations.     

Types of sesquiterpenes from Artemisia filifolia

The roots of Artemisia filifolia afforded in addition to known compounds an oxo-longipinane, a longibornan endoperoxide, two seco-longibornane derivatives and a himachalene derivative. The structures of the new sesquiterpenes were elucidated by several chemical transformations and by NMR spectroscopic investigations. Possible biogenetic pathways are discussed briefly.     

A further dithienylacetylene from Eclipta erecta

The roots and the aerial parts of Eclipta erecta afforded, in addition to compounds reported previously, a new dithienyl derivative.     

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.     

New sesquiterpene lactones,geranyllinalol derivatives and other constituents from Geigeria species

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 transformation. Chemotaxonomic aspect and relationship of the comnounds are discussed.     

A further sesquiterpene lactone esterified with a sesquiterpenic acid

The roots of Hypochoeris oligocephala afforded in addition to known compounds a further sesquiterpene lactone esterified with a sesquiterpenic acid as well as the corresponding free acid.     

Sesquiterpenes and acetylenes from Argyranthemum adauctum ssp. jacobaeifolium

The roots of Argyranthemum adauctum ssp. jacobaeifolium, a rare endemic from Gran Canaria, afforded two new derivatives of the aromatic acetylene frutescin and 8-isovaleryloxymyrcene, while the aerial parts gave a new bisabolol derivative. Furthermore several known compounds were isolated. The structures were elucidated by high field ¹H NMR spectroscopy and a few chemical reactions.     

Sesquiterpenes and norsesquiterpenes from Pechuel-Loeschea leibnitziae

The aerial parts of Pechuel-Loeschea leibnitziae afforded, in addition to thymohydroquinone dimethyl ether, sitosterol and stigmasterol, xerantholide and its probable precursor, the 11,13-dihydro derivative methyl pechueloate and two norsequiterpenes, probably formed by degradation of the corresponding sesquiterpene acid. Two eudesmane derivatives were also isolated. The chemotaxonomy of Pechuel-Loeschea is discussed briefly.     

Seven furanoeremophilanes from three Senecio species

The investigation of two further Senecio species and the re-investigation of S. inaequidens afforded, in addition to known compounds, seven new furanoeremophilane derivatives. Six of these are closely related to cacalol, a sesquiterpene type which predominates in the species investigated.     

New sesquiterpene lactones and other constituents from Fitchia speciosa

The investigation of Fitchia speciosa afforded, in addition to known compounds, three new sesquiterpene lactones, iso-β-costal, two p-hydroxyacetophenone derivatives and an isoeugenol derivative. The structures were elucidated by spectroscopic methods. The chemotaxonomic situation in this complicated genus is discussed.     

Sesquiterpenes,guaianolides and diterpenes from Stevia myriadenia

The investigation of Stevia myriadenia afforded in addition to known compounds a new clerodane and a labdane derivative, two guaianolides, a bisabolene and a germacrene derivative. The structures were elucidated by spectroscopic methods. The chemotaxonomic situation is discussed briefly.     

New germacranolides and other constituents from Trichogoniopsis morii

Trichogoniopsis morii afforded, in addition to known compounds, a new toxol derivative, two diterpenes, a labdane and an ent-kaurane derivative, an eudesmanolide and five germacranolides, a furanoheliangolide and four 1-oxo-germacranolides. The structures were elucidated by spectroscopic methods and a few chemical transformations. The chemotaxonomy of the genus Trichogoniopsis is discussed briefly.     

Allenic germacranolides,bourbonene derived lactones and other constituents from Vernonia species

An investigation of seven Vernonia species, mainly from northern Brazil, afforded in addition to known compounds three new unusual sesquiterpene lactones with an allenic group. Intensive NMR studies fully established the structures. Furthermore, two lactones derived from bourbonene, two new glaucolides, a new furansesquiterpene, a nerolidol derivative and two other sesquiterpenes derived from eudesmane were isolated. The biogenetic relationships of the sesquiterpene lactones present in Veronia species as well as the chemotaxonomic aspects are discussed.     

Neue Sesquiterpen-Kohlenwasserstoffe mit anomalen Kohlenstoffgerüst aus Silphium-arten

The non-polar fractions of some Silphium roots afforded in addition to known compounds four new sesquiterpene hydrocarbons, all based on one or other of two tricyclic compounds with anomalous carbon skeletons. The structures were elucidated by extensive NMR studies of the hydrocarbons and of a large number of oxidation products. The reaction of the corresponding diols was investigated in especial detail. A possible biogenetic pathway to the unusual hydrocarbons is proposed.     

A tetracyclic sesquiterpene,further isocedrene and guaiene derivatives from Jungia stuebelii

The aerial parts of Jungia stuebelii afforded, in addition to known compounds, two guaiene derivatives, a pseudoguaiane derivative, nine isocedrene     

Labdane derivatives from Planaltoa lychnophoroides

The investigation of a representative of the small Brazilian genus Planaltoa afforded, in addition to known compounds, a new toxol derivative and two ent-labdane derivatives, closely related to austrofolin. The structures were elucidated by high field ¹H NMR spectroscopy. The chemotaxonomic situation is discussed briefly.     

Sesquiterpene-coumarin ethers and polyacetylenes from Bfrocchia cinerea

The roots of Brocchia cinerea afforded, in addition to known spiroketalenolether polyynes and sesquiterpene-coumarin ethers, two new isofraxidin-derived sesquiterpene ethers as well as the new 8-farnesyl-scopoletin. The structures of the new compounds were elucidated on the basis of spectroscopic evidence. The chemotaxonomic significance of sesquiterpene-coumarin ether and spiroketalenolether accumulation within the tribe Anthemideae is discussed.     

Four oplopanone and bisabolone derivatives from Rugelia nudicaulis

Rugelia nudicaulis afforded, in addition to known compounds, three new highly oxygenated oplopanone derivatives and a bisabolone derivative. The structures were elucidated by high field ¹H NMR spectroscopy. The chemotaxonomic situation is discussed briefly.