Studies on the Saponins of Lonicera japonica Thunb.

Abstract

From the aerial parts of Lonicera japonica thunb.(Caprifoliaceae), twelve triterpenoidal saponins having oleanolic acid and hederagenin as aglycones, were isolated. The structures of four new saponins, 6, 9, 11 and 12, were established to be 3-0-α-L-arabinopyranosyl-28-0-[β-D-glucopyranosyl(l→ -β-D-glucopyranosyl]oleanolic acid, 3-0-[α-L-rahmnopyranosyl(l→-α-L-arabinopyranosyl]-28-0-β-D-glucopyranosyl hederagenin, 3-0-[α-L-rhamnopyranosyl(l→-α-L-arabinopyranosyl]-28-0-[β-D-glucopyranosyl(l →-β-D-glucopyranosyl]oleanolic acid and 3-0-[α-L-rhamnopyranosyl(l →-α-L-arabinopyranoyl]-28-0-[6-acetyl-β-D-glucopyranosyl(l →-D-glucopyranosyl]hederagenin, respectively, by means of carbon-13 nuclear magnetic resonance spectroscopy and chemical evidence. The present studies revealed that the saponin compositions of the materials collected at different places were significantly different from each other. Among these saponins, monodesmosides showed strong hemolytic activity, but bisdesmosides showed weak hemolytic activity. © 1988, The Pharmaceutical Society of Japan. All rights reserved.