Synthesis and characterization of cobalt and manganese complexes of indomethacin and comparative study of local analgesic, anti-inflammatory, and anti-ulcerogenic properties

The aim of the study was to synthesize cobalt and manganese complexes of indomethacin and their biological activity screening to uncover. The structures of metal complexes were elucidated by FT-IR, UV-Vis and atomic absorption spectroscopy, X-ray diffraction and calorimetric DSC. Heat radiant tail-flick test for local analgesic activity of cobalt complex of indomethacin in the doses of 50 and 100 μg/mL demonstrated potent local analgesic response. Manganese complex of indomethacin exhibited similar potent of activity at the dose of 100 μg/mL. Anti-inflammatory study of the indomethacin-manganese and indomethacin-cobalt complexes demonstrated their activity (paw edema inhibition of 71.67% at 20 mg/kg dose in the 1 h and 83.33% at 10 mg/kg dose in the 4 h) comparable with the standard diclofenac sodium. Gastrointestinal efficacy of cobalt and manganese complexes was close to that of indomethacin.