New Flavonoid Glycosides from the Leaves of Tribulus terrestris

The structures of four new flavonoid glycosides - apiotribosides A, B, C and D (1 - 4, resp.) isolated from the leaves of Tribulus terrestris L. were identified as quercetin 3- O-β-D-apiofuranosyl-(1→2)-[β-D-apiofuranosyl-(1→6)]-β-glucopyranoside (1), quercetin 3- O-β-D-apiofuranosyl-(1→2)-[α-L-rhamnopyranosyl-(1→6)]-β-D-glucopyranoside (2), isorhamnetin 3- O-β-D-apiofuranosyl-(1→2)-[β-D-apiofuranosyl-(1→6)]-β-D-glucopyranoside (3), and isorhamnetin 3- O-β-D-apiofuranosyl-(1→2)-[α-L-rhamnopyranosyl-(1→6)]-β-D-glucopyranoside (4).