New bioactive monoterpene glycosides from Paeoniae Radix

Bioassay-guided separation of MeOH extract of Japanese Paeoniae Radix inhibiting contractile responses of guinea pig ileum stimulated with electric field disclosed a new monoterpene glycoside, 6-O-beta-D-glucopyranosyl-lactinolide (1), as an active constituent together with two new monoterpene glycosides (3 and 4) and two new monoterpenes (2 and 5). Furthermore, 1-O-beta-D-glucopyranosyl-paeonisuffrone (2) was found to inhibit histamine release from rat peritoneal exudate cells induced by antigen-antibody reaction.