Ligation of Cadmium (II) complex by 2,5-diamino-1,3,4-thiadiazole and their biological activity

Abstract

This study investigated the synthesis of 2,5-diamino-1,3,4-thiadiazole, physical characteristics, antibacterial properties and toxicity implication or safety of the resulting complex using albino rats as model with a view to
searching for an effective antimicrobial drug. The complex of the type ML₂ (where M=Cd and L= 2,5-diamino-1,3,4-Thiadiazole) was prepared. The ligand (L) was prepared starting from the reaction of potassium thiocynate with semicarbazide hydrochloride to produce bithiourea. Cyclisation of bithiourea in a 3% Hydrogen Peroxide gave the ligand L. The formation of metal complex was carried out using the template method. The complex was a non-electrolyte in dimethylformamide (DMF). The elemental analysis, magnetic measurements, conductivity measurements and spectral studies were used to determine the physical characteristics of the ligand (L) and metal complex. The biological activities were screened by studying the in-vivo antimicrobial and toxicological activities. Overall, the metal complex was tentatively assigned an octahedral geometry based on spectral studies. The ligand coordinated with the metal ion through sulphur atom and nitrogen of the amines (N:S:N). A low value of conductivity revealed the non-electrolytic nature of the compound. The metal chelates possessed greater activities against bacterial strains used compared to the control drug and the ligand used. The study concluded that the metal complex showed mild toxicity at the orally administered dosage-level (0.6 mg/kg body weight) on albino rat (Wistar strain).

Keywords: Ligation, Antimicrobial, Toxicological, Cyclisation, 3% Hydrogen Peroxide