0000000000113791
AUTHOR
Vicente García-lliso
Sesquiterpene lactones and lignans from Artemisia arborescens
The aerial parts of Artemisia arborescens yielded, in addition to several known compounds, a new guaianolide, a new homoditerpene endoperoxide, a new lignan of the sesamin type and a new azulene derivative.
Influence of conformational factors on acid-catalyzed cyclizations of germacranolides: Molecular structure of the cyclization products of gallicin and 8α-hydroxygallicin (shonachalin a)
Acid-catalyzed cyclization of the natural germacranolide gallicin (8) yielded, among other products, the 1,4-epoxyeudes-manolide 9, which has a trans-fused decaline system. Under the same conditions the closely related germacranolide shonachalin A (8α-hydroxygallicin) (3) cyclized to the eudesmanolide 4 with a cis fused decaline system. The structures of these cyclization products were secured by means of chemical correlations and X-ray diffraction analyses.
Sesquiterpene lactones, lignans and aromatic esters from Cheirolophus species
Abstract The aerial parts of five Cheirolophus species yielded three new guaianolides, a new lignan and three new aromatic esters, together with other known compounds of the same type.
Sesquiterpene lactones from Artemisia lucentica
Abstract The aerial parts of Artemisia lucentica yielded, in addition to several known compounds, a bicyclic monoterpene ketone, two germacranolides, an eudesmanolide, a 10- epi neudesmanolide, a 2-norelemanolide and three bisabolene derivatives. The stereochemistry of a germacranolide, described as 2α-hydroxyartemorin in a previous investigation of the species, has now been corrected and the compound has been renamed lucentolide.