Synthesis, structural characterization and molecular modelling of bidentate azo dye metal complexes: DNA interaction to antimicrobial and anticancer activities

Abstract

A novel azo dye ligand, namely 1‐[(5‐mercapto‐1H‐1,2,4‐triazole‐3‐yl)diazenyl]naphthalen‐2‐ol (HL), was synthesized. Mn2+, Co2+, Ni2+, Cu2+ and UO22+ complexes were also prepared by the treatment of HL with Mn(CH3COO)2⋅4H2O, Co(CH3COO)2⋅4H2O, Ni(CH3COO)2⋅4H2O, Cu(CH3COO)2⋅H2O, CuCl2⋅2H2O, Cu(NO3)2⋅6H2O and UO2(NO3)2⋅6H2O. The structures of these metal chelates were confirmed using elemental, spectral, magnetic moment, molar conductance and thermal analyses. The analytical data confirmed the formation of the chelates in 1:1 (metal‐to‐ligand) ratio having the formula [ML(H2O)X]Y⋅H2O, where M is Mn2+, Co2+, Ni2+, Cu2+ or UO22+; X is Cl−, NO3− or CH3COO−; and Y is H2O. The azo compound acts in a monobasic bidentate manner via the nitrogen and oxygen atoms of azo and hydroxyl groups, respectively. All complexes were found to have tetrahedral structures, except the UO22+ complex that showed octahedral geometry. The mode of interaction between the synthesized complexes and calf thymus DNA was explored by the aid of absorption spectroscopy and viscosity measurements. The azo dye and its chelates were evaluated against the growth of various bacterial and fungal strains (Escherichia coli, Staphylococcus aureus, Aspergillus flavus and Candida albicans) with insight gained into the effect of type of metal centre, type of coordinated anion and position of the metal in the periodic table on the activity of the complexes. The geometric structure of the complexes was optimized using molecular modelling. The in vitro cytotoxicity of the synthesized compounds was tested against HEPG2 cell line.

Synthesis, structural identification, DNA interaction and biological studies of divalent Mn, Co and Ni chelates of 3‐amino‐5‐mercapto‐1,2,4‐triazole azo ligand

“…The pH was then adjusted to 7.2 using HCl] has been used as medium for the absorption and viscosity technique. [23,26] The purity of the DNA was checked by absorption spectroscopy using calculation of the molar absorption coefficient (6600 M −1 cm −1 ) by its absorbance values at λ max 260 nm and 280 nm. The ratio of A 260 /A 280 was measured to be 1.8-1.9.…”

“…Over the years, these compounds are found to possess extensive implementations in various biological applications, especially antimicrobial, anticancer and antimalarial therapy. [18][19][20][21][22] Owing to the above aforesaid significance of azo-containing ligands and in continuance to our research group interests in syntheses of azo compounds based on 3-amino-5-mercapto-1,2,4-triazole which we prospect to be good acting as anticancer, [23,24] we report herein the syntheses and study of new Mn (II), Co (II) and Ni (II) chelates of the azo ligand derived from the coupling of 3-amino-5-mercapto-1,2,4-triazole and 2,4-dihydroxybenzaldehyde. The structural characterization were achieved applying the alternative analytical and spectral tools.…”

Synthesis, characterization, structure determination from powder X-ray diffraction data, and biological activity of azo dye of 3-aminopyridine and its complexes of Ni(II) and Cu(II)

“…Cytotoxic studies of azo dye complexes against T47D, MTLn3 and RAW tumor cell lines exhibited a satisfactory inhibitory effect on cells comparable to that of cisplatin [10]. Synthesized complexes of Mn II , Co II , Ni II and Cu II of azo dye(1-[(5-mercapto-1H-1,2,4-triazole-3-yl)diazenyl]naphthalene-2-ol) exhibited attractive biological activity against many types of bacterial and fungal strains as Staphylococcus aureus, Escherichia coli, Candida albicans and Aspergillus flavus, and antitumor activity toward HEPG2 cell line [11]. 3-Aminopyridine derivatives exhibited antineoplastic activity in vivo toward the L1210 leukemia [12].…”

Synthesis, structure elucidation, DNA binding and molecular docking studies of novel copper(II) complexes of two 1,3,4‐thiadiazolethiosemicarbazone derivatives

“…The molar conductance values measured for 10 −3 M solution of the complexes dissolved in DMF was found to be within the range11.5–17.5 Ω −1 cm 2 mol −1 confirming their non‐electrolytic nature. [ 28,29 ] The compounds were found to the highly stable in air. All the isolated compounds are found to be air‐stable and readily dissolve in most polar organic solvent but slightly soluble in non‐polar solvents.…”