Triterpenoid saponins from the roots of Zygophyllum species.

Two new triterpenoid saponins, 3-O-[beta-D-2-O-sulphonylglucopyranosyl]-quinovic acid-28-O-[beta-D-glucopyranosyl] ester (zygophyloside G), 3-O-[alpha-L-arabinopyranosyl-(1-->2)-beta-D-quinovopyranosyl++ +]-quinovic acid-28-28-O-[beta-D-glucopyranosyl] ester (zygophyloside H), and seven known saponins have been isolated. The structures were established primarily on the basis of NMR spectroscopy. The assignment of all NMR signals was performed by means of 1H-1H COSY-45, NOESY, TOCSY, 13C APT, HMQC and HMBC experiments. The determination of the glycosylation sites was possible by the HMBC experiments.