Abstract: Six novel cycloartane-type glycosides were isolated from the roots of Astragalus trojanus. Two of these, compounds 1 and 2, have (20R,24S)-epoxy-3β,6α,16β,25-tetrahydroxycycloartane as the aglycon, while compounds 3−6 possess 3β,6α,16β,(24S),25-pentahydroxycycloartane as the aglycon. The saccharide moieties linked to the C-3, C-6, and C-24 or C-25 positions of the aglycons in 1−6 contained either xylopyranose, glucopyranose, rhamnopyranose, or arabinopyranose units. Structure elucidation of compounds 1−6 was accomplished through the extensive use of 1D and 2D NMR techniques. In addition, a new oleanene glycoside (7) and a new tryptophan derivative (8) were also isolated and characterized.
Secondary Metabolites from the Roots of Astragalus trojanus
AQUINO, Rita Patrizia;PIACENTE, Sonia;PIZZA, Cosimo
1999-01-01
Abstract
Abstract: Six novel cycloartane-type glycosides were isolated from the roots of Astragalus trojanus. Two of these, compounds 1 and 2, have (20R,24S)-epoxy-3β,6α,16β,25-tetrahydroxycycloartane as the aglycon, while compounds 3−6 possess 3β,6α,16β,(24S),25-pentahydroxycycloartane as the aglycon. The saccharide moieties linked to the C-3, C-6, and C-24 or C-25 positions of the aglycons in 1−6 contained either xylopyranose, glucopyranose, rhamnopyranose, or arabinopyranose units. Structure elucidation of compounds 1−6 was accomplished through the extensive use of 1D and 2D NMR techniques. In addition, a new oleanene glycoside (7) and a new tryptophan derivative (8) were also isolated and characterized.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
