Two antifungal active triterpenoid saponins from the seeds of Lathyrus plants

Two novel triterpenoid glycosides have been isolated from butanolic seeds extract of two varieties of Lathyrus plants, i.e. Lathyrus ratan and Lathyrus aphaca. Their structures were elucidated as 3-O-[β-D-glucuronopyranosyl-(1 → 4)-α-L-arabinopyranosyl-(1 → 2)-α-L-arabinopyranosyl]-olean-11,13(18)-dien-28-oic acid (1) and 3-O-{β-D-xylopyranosyl-(1  →  2)-β-D-glcopyranosyl-(1 → 4)-[β-D-glucopyranosyl-(1 → 2)]-β-D-xylopyranosyl}-2,16α-dihydroxy-4-hydroxymethyl urs-12-en-28-oic acid (2) on the basis of spectral evidences, i.e. FTIR, (1)H-NMR, (13)C-NMR, ESI-MS and FAB-MS data. The isolated saponins were tested for their antifungal activity. Compound 1 showed maximum inhibition against Colletotrichum dematium (77.8%), whereas compound 2 showed maximum inhibition against Alternaria alternata (53.9%).