Abstract
Antiallergic drugs such as disodium cromoglycate (DSCG) and tranilast are strong inhibitors
of hyaluronidase. On developing new active antiallergic agents, we aimed principally
at the inhibitory effects of hydrangenol derivatives on the activation of hyaluronidase.
Among the compounds tested, the hydrangenol derivatives, BT-1 and BT-2, showed strong
inhibitory effects. Antiallergic activities of BT-1 and BT-2 were also evident from
the fact that they inhibited the histamine release from rat peritoneal mast cells
induced by antigen and compound 48/80, and from the suppressive effect on 48 h homologous
passive cutaneous anaphylaxis (PCA) in rats.