Ngo Le Van

Terpen-derivate aus Senecio-arten

Zusammenfassung Uberblickt man das jetzt vorliegende Material uber die Gattung Senecio , so bestatigt sich die schon eingangs erwahnte Festellung, das in Eine klare Differenzierung der Gattung Senecio von den Nachbargruppen von der Seite der Inhaltsstoffe her, ist nach wie vor problematisch. Wahrsche

Neuen kaurensaure-derivate aus Wedelia-arten☆

Abstract 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 geranyl-cumarin-derivate und weitere inhaltsstoffe aus der tribus mutisieae☆

Abstract The investigation of further species of the tribe Mutisieae afforded in addition to already known compounds a new sesquiterpene derived from bisabolene, a new chromene, two benzofurans and two geranyl derivatives of typical coumarins. The chemotaxonomic importance of these compounds is discussed briefly.

β-Isocomen, ein neues sesquiterpen aus Berkheya-arten

Abstract The investigation of several Berkheya species afforded in addition to already known compounds three unusual sesquiterpene hydrocarbons. Together with modhephene and isocomene, a new one is present, its structure being elucidated by spectroscopic methods and by some chemical transformations. All 18 species investigated contain the typical thiophene derivatives, isolated earlier; the patterns of compounds present divide the species into two groups.

Neue kaurensäure-derivate und germacranolide aus Montanoa pteropoda

Abstract 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 1 H-NMR studies and some chemical transformation. The chemotaxonomical situation is discussed briefly.

Neue Guajanolide aus Podachaenium eminens

Abstract The airial parts of Podachaenium eminens contain, besides known compounds, four new guaianolides. The roots afford known acetylenes together with a new euparine-derivative. The structures are elucidated using spectroscopic methods.

Sesquiterpenlactone und polyine aus der gattung Arctotis

Abstract The South African genus Arctotis contains two polyynes sometimes together with diterpenes and sesquiterpene lactones, four of which are new. The structures have been elucidated by spectroscopic methods.

New germacranolides from Dicoma anomala

Abstract The aerial parts of D. anomala contain, besides known compounds, two new 7,8-germacranolides. The structures have been elucidated by spectroscopic methods. D. argyrophylla lacks lactones.

Neue sesqui- und diterpene aus Bedfordia salicina

Abstract An Australian member of the tribe Senecioneae, Bedfordia salicina , contains besides known compounds new dimeric eremophilenolides, new kolevane derivatives, a kaurenic acid and several further sesquiterpenes, most of them related to xanthatine. The structures are elucidated mainly by spectroscopic methods and by some chemical transformations. The chemotaxonomic aspects of these findings are discussed briefly.

Terpen-glycoside aus Melampodium divaricatum

Abstract The roots and the aerial parts of M. divaricatum contain a large variety of esterified glycosides of hydroxythymol. Their structures were elucidated mainly by spectroscopic methods.