Resin glycosides. V. Identification and characterization of the component organic and glycosidic acids of the ether-soluble crude resin glycosides ("jalapin") from Rhizoma Jalapae Braziliensis (roots of Ipomoea operculata).

Alkaline hydrolysis of the ether-soluble resin glycoside ("jalapin") fraction of the roots of Ipomoea operculata (Convolvulaceae) gave five glycosidic acids, operculinic acids A (1), B (2), C (3), D and E, along with n-decanoic and n-dodecanoic acids. Operculinic acids A, B and C were characterized to be 11S-jalapinolic acid 11-O-β-D-glucopyranosyl-(1→3)-O-[α-L-rhamnopyranosyl-(1→4)]-O-α-L-rhmnopyranosyl-(1→4)-O-α-L-rhamnopyranosyl-(1→2)-β-D-fucopyranoside, 11S-jalapinolic acid 11-O-β-D-glucopyranosyl-(1→3)-O-[α-L-rhamnopyranosyl-(1→4)]-O-α-L-rhamnopyranosyl-(1→4)-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside and 11S-jalapinolic acid 11-O-α-L-rhamnopyranosyl-(1→4)-O-α-L-rhamnopyranosyl-(1→4)-O-α-L-rhamnopyranosyl-(1→2)-β-D-fucopy6ranoside, respectively, on the basis of chemical and spectroscopic data.n-Decanoic and n-dodecasnoic acids found in this study are the first component organic acids of the resin glycosides so far studied.