Bulky amine analogs of ketoprofen: potent antiinflammatory agents

Replacement of the carboxyl group of 2-(3-benzoylphenyl)propionic acid (Ketoprofen) with various bulky amines has produced a series of highly active antiinflammatory agents that have reduced intestinal ulcerogenicity and have better therapeutic ratios in the 21-day adjuvant arthritis assay in rats than currently marketed nonsteroidal antiinflammatory drugs. Activity is maintained on reduction of these 2-(3-benzoylphenyl)propyl bulky amines to the corresponding alcohols or methylene analogues, on conversion of the ketone function to a primary amine or oxime, and on introduction of a 4-halo substitutent (Cl or F) on the terminal aromatic ring. Removal of the alpha-CH3 group greatly reduces the antiinflammatory activity of the series. These compounds have been synthesized by the reductive amination of 2-(3-bromophenyl)propionaldehyde with the respective amine followed by lithiation of this product and condensation with the appropriate benzonitrile.