Biological Study of Transition Metal Complexes with Adenine Ligand

Adenine complexes were prepared with some of the first series transition metals in a stoichiometric ratio of 1: 2 (Mn+: L), where Mn+ = Mn2+, Fe3+, Co2+, Ni2+, Cu2+, Zn2+, and Cd2+ ions. The Complexes were characterized by the physicochemical and spectroscopic techniques as electric conductivity, metal contents, IR, UV–Visible, and molar conductance techniques. The stoichiometric ratios of the synthesized complexes were confirmed by using molar ratio method. The dissociation constant of adenine ligand was determined spectrophotometrically. Solvent effect on the electronic spectra of the adenine ligand was examined using solvents with different polarities. The biological activity of adenine ligand and its metal complexes were tested in vitro against some selected species of fungi and bacteria. The results showed a satisfactory spectrum against the tested organisms.

Reversible Oxygenation of 2,4-Diaminobutanoic Acid-Co(II) Complexes

This paper introduces the structural characterization and studies on reversible oxygenation behavior of a new oxygen carrier Co(II)-2,4-diaminobutanoic acid (DABA) complex in aqueous solution. The composition of the oxygenated complex was determined by gas volumetric method, molar ratio method, and mass spectrometry, and the formula of the oxygenated complex was determined to be [Co(DABA)2O2]. In aqueous solution, the complex can continuously uptake and release dioxygen and exhibit excellent reversibility of oxygenation and deoxygenation ability. This complex can maintain 50% of its original oxygenation capacity after 30 cycles in 24 h and retain 5% of the original oxygenation capacity after more than 260 cycles after 72 h. When a ligand analogue was linked to histidine (His), the new complex exhibited as excellent reversible oxygenation property as His-Co(II) complex. Insight into the relationship between structural detail and oxygenation properties will provide valuable suggestion for a new family of oxygen carriers.

Spectrophotometric Determination of Selenium in Various Samples Using 5,6-Diaminouracil Hydrochloride (DAUH)

A simple, rapid and sensitive spectrophotometric method was developed for the determination of Se (IV) using 5,6-diaminouracil hydrochloride (DAUH) as an analytical reagent. The reagent has been synthesized and characterized using IR, 1H NMR. The metal ion in aqueous medium forms yellow colored complex with DAUH showing maximum absorbance at 343 nm. Hence, analytical studies were further carried out at 343 nm. The reagent reacts with selenium in acidic medium to form yellow colored 1:1 (M:L) complex . The color reactions are instantaneous and absorbance values remain constant for one week. The composition of the Se (IV) complex with DAUH was studied by the method of job’s continuous variation and molar ratio method. Beer’s law was obeyed in the range 0.2-15.0 μg mL−1of Se (IV). The molar absorptivity and Sandell’s sensitivity of the method were found to be 0.5×10+4 L.mol-1.cm-1and 0.031μg.cm-2 respectively. Since DAUH method is more sensitive, it was applied for the determination of selenium in samples.

Synthesis, spectroscopic study of Pt (IV), Au (III), Rh(III),Co(II) and V (IV) complexes with sodium[5-(p-nitro phenyl) -/4- phenyl-1,2,4-triazole-3-dithiocarbamato hydrazide] and cytotoxicity assay on rhabdomyosarcoma cell line of heavy metals

All the prepared metal complexes of Pt (IV), Au(III), Rh (III), Co (II) and V(IV) with new ligand sodium [5-(p-nitro phenyl)-/4-phenyl-1,2,4-triazole-3-dithiocarbamato hydrazide] (TRZ.DTC) have been synthesized and characterized in solid state by using flame atomic absorption, elemental analysis C.H.N.S, FT-IR ,UV-Vis Spectroscopy, conductivity and magnetic susceptibility measurements. The nature of the complexes formed in ethanolic solution has been studied following the molar ratio method also was studied stability constant and found to be stable in molar ratio1:1 of VL (IV) and CoL(II) while Pt(IV), Au(III) and Rh(III) complexes stable in molar ratio 1:2 as well as the molar absorptivity for these complexes were calculated. From the previous analyses, octahedral geometry was suggested for Pt (IV), Rh (III) and Co (II) complexes, square planar was suggested for Au(III) complex while V(IV) complex has a square pyramidal. Cytotoxic effect of PtL, AuL and RhL as well as ligand has been evaluated against RD cell line by using four different concentrations (500, 250, 125 & 62.5 µg/ml) respectively in three exposure times 24, 48 and 72 hrs and compared this effect with control positive Cis-Pt.

Spectral Characterization and Antibacterial Activities of Benzyloxybenzaldehydethiosemicarbazone, 3,4-Dihydroxybenzaldehydeisonicotinoylhydrazone and their Transitional Metal Complexes

The synthesis and spectral characterization of benzyloxy-benzaldehydethiosemicarbazone (BBTSC) and the study of antibacterial activity of ligands BBTSC, 3,4-dihydroxybenzaldehydeisoni- cotinoylhydrazone (3,4-DHBINH) and their transition metal complexes was studied. The composition of the metal complexes was also evaluated by using Job’s method, molar-ratio method and Asmus’ method. The antibacterial activities of BBTSC, 3,4-DHBINH and their complexesi.e., Cu(II)-BBTSC, Pd(II)-BBTSC, Cr(VI)- 3,4-DHBINH, Ti(IV)- 3,4-DHBINH and Pd(II)-3,4-DHBINH were studied against two gram positive bacteria and two gram negative bacteria. Antibacterial activities were evaluated by agar cup well method with the help of Luria Bertoni plates.

Preparation, Characterization and Antimicrobial Activity Study of Some Transition Metal Complexes of 4-Flourophenyl -4-Nitrobenzylidene

A new Schiff base of 4- flourophenyl-4- nitrobenzyliden (L) ,was prepared and used to prepare a number of metal complexes with Cr (III) , Fe (III), Co(II) ,Ni (II) and Cu (II). These complexes were isolated and characterized by (FITR),UV-Vis spectroscopy and flame atomic absorption techniques in addition to magnetic susceptibility, and conductivity measurements. The study of the nature of the complexes formed in ethanol was done following the molar ratio method gave results, agreed with those obtained from isolated solid state studies. The antibacterial activity for the ligand and its metal complexes were examined against two selected microorganisms, Pseudomonas aeruginosa and Staphylococcus aureus.The results indicated that the complexes show the enhanced activity in comparison to the free ligand; these were attributed to the synergetic effect between the metal ion and the ligand in addition to the difference in the structural varieties.