Transition Metal Complexes with Mixed Nitrogen-Sulphur (N-S) Donor Macrocyclic Schiff Base Ligand: Synthesis, Spectral, Electrochemical and Antimicrobial Studies

• Published in: International journal of electrochemical science Vol. 8; no. 5; pp. 6972 - 6987
• Main Authors: Shiekh, Rayees Ahmad, Rahman, Ismail Ab, Malik, Maqsood Ahmad, Luddin, Norhayati, Masudi, Sam’an Malik, Al-Thabaiti, Shaeel Ahmed
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.05.2013
• Subjects: Antimicrobial activities; Complexes; N-S donor; Schiff base; Schiff base; Antimicrobial activities; Complexes; N-S donor
• ISSN: 1452-3981; 1452-3981
• DOI: 10.1016/S1452-3981(23)14821-8

A new mixed thia-aza-oxo macrocycle schiff base viz., 1,10-dithia-3,8,12,17-tetraoxo-4,7,13,16-tetraazacyclooctadecane with a series of transition metals Cu(II), Co(II), Ni(II) and Mn(II) has been synthesised by the [2+2] condensation of thiodiglycolic acid and ethylenediamine. Different techniques like FTIR, 1H NMR, ESI MS, UV-Vis spectroscopy, conductivity and magnetic measurements were used to investigate the structural features of the synthesised compounds. Electronic absorption and IR spectra indicate octahedral geometry for chloro and nitrato complexes and square geometry for all sulphato complexes. The redox behaviour was investigated by cyclic voltammetry and show metal centered reduction process for all complexes. The reduction and oxidation potential depends on the structure and conformation of the central atom in the coordination compounds. The complexes of Cu(II) show both oxidation and reduction process. These metal complexes were also tested for their in vitro antimicrobial activities against some bacterial and fungal strains to assess their inhibiting potential and the activities shown by these complexes were compared with standard drugs.