Biological Screening Studies of DNA Relate Metal Complexes from Benzylidene-4-imino-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one and 2-aminothiazole

Abstract

Novel terdentate cationic complexes of Cu(II), Ni(II), Co(II), Mn(II) and Zn(II) ion have been prepared using a Schiff base derived from benzylidene-4-imino-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one and 2-aminothiazole. The structural features of metal-chelates have been confirmed by micro-analytical data, FAB-Mass spectra, powder XRD, SEM, FTIR, UV-visible, 1 H NMR, EPR, CV and thermal analysis techniques. The analytical data of the complexes correspond well with the general formula [ML2]Cl2. The high conductance data of metal chelates supports their 1:2 electrolytic nature. The magnetic susceptibility and electronic absorption spectra of the complexes indicate that all the metal-chelates exhibit octahedral geometry around the central metal ion. Powder XRD data and SEM images persist that the complexes are nano size grain with polycrystalline structure. DNA interaction studies of [CuL2]Cl2 complex have been done by electronic spectral and cyclic voltammetric measurements which revealed that the binding occurs through intercalation between complex and DNA interaction of [CuL2]Cl2 complex with CT-DNA leads to hypochromism. The MIC values against the growth of microorganisms are lower for metal chelates than the ligand. This is mainly due to lipophilicity of metal ion in complexes.

Electrochemical behavior, structural, morphological, Calf Thymus-DNA interaction and in-vitro antimicrobial studies of synthesized Schiff base transition metal complexes

“…The stock solutions (10 −2 mol L −1 ) were prepared by dissolving the compounds in dimethyl formamide and the solutions were serially diluted in order to find the Minimum Inhibitory Concentration (MIC) values. In a usual procedure, a disc made on the agar medium which is previously inoculated with microorganisms [29]. The prepared compounds were tested against some fungi (72 h) and bacteria (48 h) to provide the minimum inhibitory concentration (MIC) for each compound.…”

Synthesis of substituted heterocyclic with their cobalt(Ⅱ) complexes from 2-amino- thiazoles and evaluation of their biological activity

“…Complex (15) was prepared from ligand (8) and result in 43% yield as an orange (m.p. 250-253 ºC), FT-IR (KBr, ν, cm -1 ) 3040 (C-H arom.…”

“…Schiff base compounds were prepared through the condensation of 2-amino-4-phenylthiazole compounds with benzaldehyde and its derivatives in absolute ethanol. These compounds were characterized using infrared spectroscopy, which provided distinctive bands at the frequency range [15] of (1643-1691) cm -1 which belonged to the (C=N) functional groups, and after coordination with cobalt metal (11)(12), a shift in the band towards a shorter wavelength was observed by (2-8 cm -1 ) approximately [16]. Similarly, the formula of these compounds was confirmed using 1 H NMR spectroscopy, which showed a signal around (8.82 ppm) attributed to the 1H proton of imine carbon.…”

“…Preparation of thiazolidine-4-one (8,15) This compound was prepared by reaction of Schiff base, previously prepared (3), with thioglycolic acid. The reaction involves the electron pair of the sulphur atom in thioglycolic acid attack the carbon atom of the imine group of the Schiff base.…”