Study of the anti-inflammatory and analgesic effects of novel rigid benzofuran-3, 4-dihydroxy chalcone by formalin, hot-plate and carrageenan tests in mice.

It is reported that dihydroxy chalcones have analgesic and anti-inflammatory effects. Study of the structure activity relationship (SAR) shows that benzofuran-3-one derivatives may be more effective in this respect. In this study, a new (Z)-2-(3,4-dihydroxybenzylidene)-5-methoxybenzofuran-3(2H)-one (compound 5) was synthesized and its analgesic and anti-inflammatory effects were evaluated by formalin, carrageenan and hot-Plate methods in mice. The results showed that, compound 5 induced significant antinociceptive and anti-inflammatory effect (P<0.01). Maximum analgesia (42.6%) was obtained at dose of 25 mg/kg in the first phase of formalin test. The effect of compound 5 was higher (87.7%) in chronic phase of inflammation induced by formalin (P<0.01). Administration of 25 mg/kg of compound 5 inhibited the inflammation induced by carrageenan, 32.8% and 41.7%, 1 and 3 hour after carrageenan injection, respectively. In addition, this dose of compound 5, induces significant analgesia (20.2%) in hot plate test 45 minutes after injection (P<0.01). Therefore it seems that compound 5 has potential for discovery of a compound with potent anti-inflammatory and analgesic effects and its scaffold could be use for further structural modifications.