Diterpenes with a new carbon skeleton from Printzia Laxa

The aerial parts of the South African composite Printzia laxa contain two manoyl oxides and three clerodane derivatives together with two further acids, which belong to a new type of diterpene, biogenetically closely related to the clerodanes. The structures have been elucidated by spectroscopic methods. The constituents may indicate some relationship of Printzia to the tribe Astereae.     

Kingidiol,a kolavane derivative from Baccharis kingii

The aerial parts of Baccharis kingii afforded quercetin 3,3′-dimethyl ether and a new diterpene closely related to hautriwaic acid. Structure and     

A diterpene acid from baccharis tucumanensis

The new clerodane diterpene 1 was isolated from the aerial parts of Baccharis tucumanensis (Compositae). Its structure has been determined from spectral data combined with chemical transformations.     

A carotane derivative and a eudesmanolide from Inula crithmoides*

The aerial parts of Inula crithmoides afforded a new carotane derivative and a eudesmanolide, inucrithmolide. The most probable structures were elucidated by the spectroscopic data and by some chemical transformations.     

A kolavane derivative from Liatris scariosa

A new kolavane derivative, 18-acetoxy-kolav-3-en-15-oic acid, has been isolated from Liatris scariosa.     

A germacranolide and a longipinene derivative from Eupatoriadelphus purpureus

The roots of Eupatoriadelphus purpureus contain tridecapentaynene, β-pinene and five p-hydroxyaecetophenone derivatives. By contrast, the aerial parts have germacrene D, lupeol and its isomers, coumarin, a new sesquiterpene tiglate and a new germacranolide.     

A diterpene related to erythroxydiol from Helichrysum refluxum

From Helichrysum refluxum, in addition to known compounds, a diterpene acid related to erythroxydiol Z was isolated. The structure was elucidated by NMR techniques.     

Diterpenes from Heteropappus altaicus

The aerial parts of Heteropappus altaicus afforded, in addition to more widespread compounds and known clerodane derivatives, three new ones and a seco-clerodane acid. Furthermore, a neryl geraniol derivative was present. The structures were elucidated by spectroscopic methods. The stereochemistry was solved by NOE difference spectroscopy and by the Horeau method.     

Neue chalkon-derivate und humulon-ähnliche verbindungen aus Helichrysum-arten

The investigation of two further Helichrysum species afforded in addition to known compounds three new prenylated chalcones and two humulone-like compounds. The structures were elucidated by spectroscopic methods and some chemical transformations. The chemotaxonomic situation is discussed briefly.     

A dehydrofarnesol derivative from Stomanthaes africanus

Stomanthes africanus afforded several p-hydroxyacetophenone and dehydronerolidol derivatives. Furthermore, a new dehydrofarnesol was isolated. The chemotaxonomy is discussed briefly.     

Eudesmanolides from Dimerostemma brasilianum

The investigation of Dimerostemma brasilianum afforded, in addition to known compounds, 18 new eudesmanolides and a new diterpene lactone derived f     

Diterpenes derived from clerodanes from Pulicaria angustifolia

The investigation of Pulicaria angustifolia afforded, in addition to known triterpenes and caryophyllene epoxide, four methyl esters of diterpenes, all derived from clerodane. Three of them are derivatives of seco-nidoresedic acid. The structures were elucidated by spectroscopic methods.     

Germacranolides from Inula cappa

Authentic Inula cappa DC afforded a known and four unknown germacranolides related to the ineupatorolides as well as a new 2,3-dihydroxy-9-angeloxygermacra-4-en-6,12-olide. A collection previously described as Inula cappa which yielded only flavones was identified as Blumea balsamifera DC.     

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.     

Exudate flavonoids in three persian asteraceae species

Aereal parts of three Asteraceae from Iran have been analysed for exudate flavonoids. Artemisia oliveriana, Pulicaria gnaphalodes and Tanacetum polycephalum are shown to accumulate mostly 6-methoxylated flavonols and flavones as external aglycones.