Antinociceptive properties of chalcones. Structure-activity relationships

Eleven chalcones were prepared and tested as antinociceptive agents using t he writhing test in mice. Some compounds, given intraperitoneally, caused p otent and dose-related antinociception, being several times more active tha n some reference drugs. The results evidenced that some physico-chemical pa rameters are involved in the pharmacological activity. 3,4-Dichlorochalcone (2) was the most effective compound, and was also studied in another model of pain in mice, the formalin test. Here it inhibited only the inflammator y pain (second phase), being equipotent to the reference drugs.