ABSTRACT
In the present work, binary complexes of Copper(II), Cadmium(II) and Zinc(II) with metformin hydrochloridehave been studied potentiometrically. Stability constants of binary complex systems have been estimated by themethod proposed by Irving-Rossotti at 25ºC and 0.11M ionic strength (NaClO4) in aqueous solution. Theconditional formation constants of the complexes formed between ligand and metal were calculated according topH function. The maximum values of the conditional formation constants were found to be in accordance with themixed metal-ligand complex formation constants in a given pH region. In addition to these, the molar fractionswere calculated using the formation constants of the mixed metal-ligand complexes. As a result of theexperimental study, the values of stability constants of metal-ligand complexes at 25ºCare as noted below:logK1=8.45; logK2=8.30 for Zn(II)-Metformin hydrochloride; logK1=8.78 ; logK2=8.00 for Cu(II)-Metforminhydrochloride: logK1=8.18; logK2=7.36 for Cd(II) – Metformin hydrochloride.
ABSTRACT
OBJECTIVE@#To evaluate the antibacterial and antifungal effects of cadmium(II) complexes with hexamethyltetraazacyclotetradecadiene ligands.@*METHODS@#Five coordinated square pyramidal cadmium(II) complexes and six coordinated square octahedral cadmium(II) complexes have been synthesized by interaction of 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene (denoted by L.2HClO4) and C-chiral isomers of its saturated analogue (denoted by 'teta' and 'tetb') with different salts of Cd(2+) ion [e.g. CdI2, Cd(NO3)2·6H2O, CdCl2·2H2O and Cd(ClO4)2·6H2O] in methanolic solution. Complexes of the ligands were investigated for antibacterial activity by disc diffusion method and antifungal effect by poisoned food technique.@*RESULTS@#The newly synthesized cadmium(II) complexes of the ligands were screened as potential antimicrobial agent against a number of medically important bacteria (Staphylococcus aureus, Bacillus cereus, Salmonella typhi, Shigella dysenteriae and Escherichia coli) and against two fungi (Candida albicans and Aspergillus aculeatus). The growth inhibiting activity of the ligands and complexes against bacteria and fungi were compared with the standard antibiotic ampicillin and commercially important antifungal agent, griseofulvin respectively. Among them some of the macrocyclic complexes were found to be more fungitoxic and antibacterial than the reference antifungal drug griseofulvin and antibacterial drug ampicillin respectively.@*CONCLUSIONS@#Hexamethyltetraazacyclotetradecadiene ligands and its complexes could be considered as very potential antibacterial and antifungal agent with further investigation.
ABSTRACT
Objective: To evaluate the antibacterial and antifungal effects of cadmium(II) complexes with hexamethyltetraazacyclotetradecadiene ligands. Methods: Five coordinated square pyramidal cadmium(II) complexes and six coordinated square octahedral cadmium(II) complexes have been synthesized by interaction of 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene (denoted by L.2HClO