Syntheses and structural studies of metal complexes of sulfa drugs

• Main Author: Hossain, G. M. Golzar
• Published: Cardiff University 2005
• Subjects: 541
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.583722

This thesis presents the results of the synthesis of metal complexes of sulfa drugs (sulfadiazine, sulfamerazine, sulfamethazine, sulfathiazole and sulfadimethoxine) with secondary ligands, which were subjected to X-ray crystallographic studies. The aim of this work was to synthesise metal complexes of sulfa drugs with secondary nitrogen donor ligands e.g. ammonia, pyridine (py), ethylenediamine (en), diethylenetriamine (dien), 2,2'- bipyridine, 1,10-phenanthroline, 4,4'-dimethyl-2,2'-bipyridine, A(3-aminopropyl)-bis- (ethylenediamine) (apen) and oxygen donor ligands such as, water and dimethylformamide (DMF) and to investigate the different modes of coordination of the sulfa drugs molecules to the metal ions in the presence of nitrogen/oxygen donor ligands. Chapter 1, details an introduction into the fundamental concepts, procedures and equipment involved in data collection, solution and refinement of single crystal structures. In Chapter 2, a review of the literature on the metal complexes of sulfa drugs along with the main aims of this work is presented. In Chapter 3, the general experimental procedure and synthetic methods have been described for the metal complexes of sulfa drugs whose results and discussion are described in chapter 4. In chapter 4, the crystal structure of sulfadiazine, a new polymorph of sulfamerazine and the syntheses of the metal complexes of sulfadiazine, sulfamerazine and sulfamethazine, their analytical and spectral data along with the X-ray structure determination of the complexes are presented. The complexes studied in this chapter are: A) Cobalt complex { Co(smz)2(H20) .DMF} (3) B) Nickel complexes Ni(en)3(sdz)2 .H20 (4) and Ni(smr)2(py)2 .4py (5) C) copper complexes Cu(en)2(sdz)2 (6), Cu(dien)2(sdz)2 (7), Cu(en)2(H20)2 smr)2 (8), Cu(en)2(H20)2 smr)2 .H20 (9), Cu2(smr)4 .2DMF (10), Cu2(smr)4 .2DMSO (11), Cu(smz)2(apen) .3H2O.CH3OH (12) and { Cu(smz)2.NH3 .2H20}w (13) D) Zinc complexes Zn(smz)2(NH3)2 (14) and Zn(smz)2(py)2 .2py (15), E) Cadmium complexes Cd(dien)2(sdz)2 .DMF (16), Cd(dien)(smr)2 .H20 (17), Cd(sdz)2(bpy) (18), Cd(sdz)2(phen) (19), Cd(sdz)2(dmbpy) .2DMF (20), Cd(smr)2(phen) (21), { Cd(smz)2(H20) .DMF}/I (22), { Cd(smz)2(H20) .2H20} (23) and Cd(smz)2(en) .2DMF (24) and F) Mercury complexes Hg(sdz)2(DMF)2 (25), Hg(smr)2 (26) Hg(smr)2(bpy) (27) and Hg(smz)2(DMF)2 (28). The structural results for the complexes are discussed and compared with other related complexes. In this context, the different types of coordination geometries, important parameters within the coordination sphere, the various modes of coordination of the sulfa drugs in the anionic form, dimeric polymeric complexes, the role of hydrogen bonds in the formation of the "cation-anion pair" and the packing diagram have been discussed. In Chapter 5, we have described the syntheses and characterisation of the complexes of sulfathiazole, their analytical and spectral data along with the X-ray structure determination of these complexes are presented. The complexes studied are: (H2stz)2 N03 .H20 (29), CoCl4 (H2stz)2 .CH3COOH (30) and Cu(en)2(H20)2 stz)2 .2H20 (31). In all the complexes the sulfathiazole molecules act as ionic species. The structural results for the complexes are discussed and compared with other related complexes. In this context, the role of hydrogen bonds in the formation of the "cation-anion pair" and the packing diagram has been discussed. Chapter 6 describes the structure of sulfadimethoxine and synthesis and characterisation of a zinc complex of sulfadimethoxine Zn(sdm)2(NH3)2 .2H20 (33) by analytical and spectral data along with the X-ray structure determination. The structural results of the complex are discussed and compared with other related complexes. The packing diagram of the complex with the hydrogen bonds is discussed in this chapter.