Benzofuranones as potential antinociceptive agents: structure-activity relationships.

This work evaluates the antinociceptive properties of benzofuranones using chemically induced models of pain and the hot plate test. All the compounds exhibited significant antinociceptive activity, with 3-[2-(4-chlorophenyl)-2-oxoetil]-2-benzofuran-1(3H)-one (3d) being the most active. According to the application of the Topliss method, the 2π-π(2) parameter was the preponderant one, indicating that the hydrophobicity (π) seems to be more involved in the antinociceptive activity.