.J. Indian Chern. Soc., NOTE Vol. 72, November 1995, pp. 803-804 Synthesis and Characterisation of Divalent Metal Complexes of Diclofenac Sodium RACIINA KESIIARWANI* and PRAMILA SINGH Department of Chemistry. Dr. H. S. Gour Univerbity, Sagar-470 003 Manuscript received 19 October 1993. revised 18 April 1994. accepted 22 Ju(v 1994 Diclofenac sodium(I), an effective and well-tolerated non-steroidal anti-in11ammatory agent, is used in the treatment of rheumatoid arthritis and other inflamma- tory cnndilionsl. A variety of recent observations in- dicated that copper complexes when administered in conjunction with anti-inllammatory drugs exhibit syn- ergistic activity 2 . It has also hecn found that the Cu complexes of some antiarthritic drugs arc themselves more active as anti-in11ammatory agents than their pru·- ent cumpounds 3 .4. We therefore have undCJtakcn the investigation of the interaction of Con, Nin and Cull metal ions with didofenac sodium. The study of the stereochemistries and chemical reactivity ofthe coordination compounds of the drug will help to determine the relationship be- tween chemical structure and biological activity of the drugs. Results and Discussion Physical and analytical data of the complexes arc listed in Tahle I. The complexes are microcrystalline, high-spin, soluble in DMF and J>MSO. The Coil and Cull complexes arc of compru·able ther- mal stability and the corresponding Ni 11 complex is thermally less stable. Greater stability may he attrib- uted to stabilisation by Jahn-Teller distmtion for Co 11 and Cu 11 complexes as compared to the Ni 11 com- plexes II. The complexes have low conductance value in DMF at I0- 3 M concentration ( 13.12, l 0.66 and Y.X4 n I cm2mol- 1 respectively for the Coli, Ni 11 and Cull complexes) which indicates non-electrolytic nature ot the complexes. The con, Nin and Cull complexes ex- hibit magnetic moments values of4.5, 3.7 and 1.7 B.M. respectively, indicating the presence of three, two and one unpaired electron, showing paramagnetic ch'J,rac- ter. Electronic spectra of the Coil complex in DMF show bands at 18416-18 691 and 31055 em 1 due to transition 4 Ttg(F) 4 T 1 g (P) and charge transter re- spectively, suggesting an octahedral geometry 6 around the metal ion. The Nin complex exhibits hands at 14 705-14 925 and shoulder at 25 641 cm- 1 which may be assigned to the transitions 3 A 2 g(F) 3 T 1 g (F) v 2 and 3 A 2 g(F) 3 T 1 g (P) v 3 respectively, suggest-