a study on the analgesic effects of four new derivatives of 3-hydroxy pyridine-4-one

derivatives of pyridine-4-one are iron chelators with various biological activities including antifungal, anti-malarial, antiviral, anti-inflammatory and analgesic activities. this study was aimed to evaluate the analgesic effect of four new derivatives of 3-hydroxy pyridine-4-one in animal models. acetic acid-induced writhing and formalin tests were used to assess the analgesic activity in male mice (18-22 g). compound a (2.5-10 mg/kg), b (100-400 mg/kg), c and d (50-200 mg/kg) were administered intraperitoenally. indomethacin and morphine were used as reference analgesic drugs. all tested compounds showed significant analgesia in acetic acid-induced writhing and the second phase of formalin test. all compounds except compound b also had analgesic activity in the first phase of formalin test. among the investigated compounds, compound a which showed analgesic activity at doses of 2.5-10 mg/kg considered as the most potent analgesic compound. structurally compound a lacks polar moieties such as –oh or –cooh and is less polar than the others. therefore it seems that it has a better penetration into lipophilic sites of action.