Abstract
Seven new triterpenoid saponins were isolated and identified from the aerial parts of
Fagonia arabica. They were characterized as
3-O-β-
d-xylopyranosyl
(1 → 2)-[β-
d-glucopyranosyl
(1 → 3)]-α-
l-arabinopyranosyl
oleanolic acid
28-O-β-
d-glucopyranoside
,
3-O-β-
d-glucopyranosyl
(1 → 2)-[β-
d-glucopyranosyl
(1 → 3)]-α-
l- arabino
pyranosyl oleanolic acid
28-O-β-
d-glucopyranoside
,
3-O-β-
d-xylopyranosyl
(1 → 2)-[β-
d-glucopyranosyl
(1 → 3)]-α-
l-arabinopyranosyl
oleanolic acid,
3-O-β-
d-glucopyranosyl
(1 → 2)-[β-
d-glucopyranosyl
(1 → 3)]-α-
l-arabino
pyranosyl oleanolic acid,
3-O-β-
d-xylopyranosyl
(1 → 2)-[β-
d-glucopyranosyl
(1 → 3)]-α-
l-arabinopyranosyl
27- hydroxyoleanolic acid,
28-O-β-
d-glucopyranoside
,
3-O-β-
d-xylopyranosyl
(1 → 2)-[β-
d-glucopyranosyl
(1 → 3)]-α-
l- arabinopyranosyl
ursolic acid
28-O-β-
d-glucopyranoside
and
3-O-β-
d-xylopyranosyl
(1 → 2)-[β-
d-glucopyranosyl
(1 → 3)-α-
l-arabinopyranosyl
27-hydroxyursolic acid
28-O-β-
d-glucopyranoside
. The structures of the sapomins were established by analyses of their
1H and
13C NMR spectra with the aid of 2D experiments. The two genins, 27-hydroxyoleanolic acid and 27-ursolic acid, are new.