Helenanolides, Guaianolide Glucosides and other constituentsof two Helenium donnianum varietes

SILVA, G., PACCIARONI, A., OBERTI, J. C., ARIZA ESPINAR, L., DÍAZ, J. AND WERNER HERZ

PHYTOCHEMISTRY

Pergamon elservier Science. Oxford

Lugar: Washington; Año: 1992 vol. 31 p. 1621 - 1621

0031-9422

dir> Extraction of the aerial part of Helenium donianum var. donianum and H. donianum var. linearifolium is described. An array of known and new helenanolides, guaianolide glucosidess and lavandulyl-type glucosides was isolated from H donianum var. donianum, while H. donianum var. linearifolium considtently yielded a different combination of known and new helenanolides, a new guaianolide and a known guaianolide rhhamnoside. The results are in agreement with Bierner`s classification of H. donianum in Argentina and correct misidentification of collections studied earlier. The C-2 stereochemistry of the helenanolides alternilin and flexuosin and the C-1 stereochemistry of some known guaianolides is corrected.