Neue labdan-derivate aus Aristeguietia buddleaefolia

The aerial parts of Aristeguietia buddleaefolia afforded, in addition to known compounds, three new diterpenes, all being 12, 13-E-abienol derivatives. A further diterpene turned out to be jhanidiol-18-O-acetate, isolated earlier from an Ageratina species. Furthermore two derivatives of hydroxy dihydroconiferyl alcohol are present. The structures were elucidated by spectroscopic methods and by some chemical transformations.     

Neue labdan-derivate aus Gutierrezia-arten

The aerial parts of Gutierrezia lucida afforded three new diterpenic acids, all closely related to agathic acid and those of G. mandonii also three diterpenic acids, which again are labdane derivatives. The structures were elucidated by spectroscopic methods and some chemical transformations. The roots of these species and of a further one only contain triterpenes and no acetylenes. The chemotaxonomic situation is briefly discussed.     

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 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 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 diterpene und germacranolide aus Mikania-Arten

From three Mikania species, three new labdanic acid and two kaurenic acid derivatives have been isolated together with known compounds and four new germacranolides, differing only in the ester moiety.     

Neue ent-labdan-derivate aus Austroeupatorium chaparense

The aerial parts of A. chaparense afforded, in addition to known compounds, five new ent-labdane derivatives, while Campovassouria bupleurifolia contains mainly kaurene derivatives. The chemotaxonomic situation is 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 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 diterpene und acetylenverbindungen aus Nidorella-arten

The investigation of four species of the South African genus Nidorella afforded three new clerodane derivatives, nidorellalactone, isonidorella     

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.     

Neue diterpene aus Schkuhria-arten

The investigation of two further Schkuhria species afforded, in addition to several known compounds, three new diterpenes from the labdane series of the manoyl oxide type. The structures were elucidated by spectroscopic methods and by some chemical transformations, although the absolute configuration and that at C-13 could not be established with certainty. Furthermore a new thymol derivative was obtained. The chemotaxomonic 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.     

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.