New solvatochromic complexes of 1,2‐bis[(5,6‐diphenyl‐1,2,4‐triazin3‐yl)hydrazinylidene‐methyl]benzene: Synthesis, spectroscopic, biological, docking, and theoretical studies

Abstract

A new bistriazine hydrazone ligand (H2L; H2BDTB) is derived from 5,6‐diphenyl‐1,2,4‐triazine‐3‐ylhydrazine (DTH) with o‐phthalaldehyde in ratio (2:1). The Fe(III), Co(II), Ni(II), Cu(II), and Th(IV) complexes (1–5), as well as the Co(II) complex (6) (prepared in the presence of cetyltrimethylammonium bromide [CTAB]), are synthesized. They are characterized by elemental analyses, spectral (ultraviolet–visible [UV–Vis], infrared [IR], mass, 1H NMR, and electron spin resonance [ESR]), magnetic susceptibility, molar conductivity, and thermal gravimetric analysis (TGA) measurements; and morphological structures are scanned by electron microscopy (SEM) that showed rod shape, irregular bulk sheets, and fused aggregated clusters for free ligand, Co(II) complexes (2 and 6), respectively. Moreover, cobalt(II) complex (6) exhibited an octahedral geometry; however, cobalt(II) complex (2) showed square planar geometry as deduced from magnetic moment and UV–Vis measurements. Fluorescence spectra for ligand and its Fe(III) and Th(IV) complexes have been measured in different solvents to investigate their solvatochromic behavior that used to estimate dipole moments either in ground and excited states. The antimicrobial and antitumor activities of free ligand and its complexes were investigated, in addition to molecular docking studies using MOE 2014.0901 software (PDB. I.D.3ce3). The data showed that Co(II) complex (6) can be nominated as one of the most powerful antitumor. The theoretical calculation for bistriazine ligand and its complexes were performed using DFT and PM3, and the data are correlated with the experimental results.

Co (II), Ni (II), and Cu (II) complexes of 4,6‐bis(2‐hydroxynaphthalen‐1‐yl)methyl‐ene)hydrazono)ethyl)benzene‐1,3‐diol: Synthesis, spectroscopic, biological, and theoretical studies

“…On the other hand, the negative values (−13.20 to −112 Jmol −1 ) indicate that the reactants are less ordered than the activated complex and/or the reactions are slow. The positive values of ∆G* (24.34–95.18 kJmol −1 ) illustrate the autocatalytic action of metal ions on thermal decomposition of the chelates and nonspontaneous processes. [ 96 ] …”

“…d. The positive values of ΔG* (24.34-95.18 kJmol À1 ) illustrate the autocatalytic action of metal ions on thermal decomposition of the chelates and nonspontaneous processes. [96]…”

Antibacterial and anticorrosion behavior of bioactive complexes of selected transition metal ions with new 2‐acetylpyridine Schiff base

“…Schiff bases have been regarded as important ligands due to their contribution to coordination chemistry due to their variable bonding, structural possibilities, and their applications in several fields; they can be simply prepared and associated with many metal ions without any requirement of purification because water is the only byproduct of condensation. [ 1–3 ]…”

“…Schiff bases have been regarded as important ligands due to their contribution to coordination chemistry due to their variable bonding, structural possibilities, and their applications in several fields; they can be simply prepared and associated with many metal ions without any requirement of purification because water is the only byproduct of condensation. [1][2][3] They have an amine group, similar to the natural biological systems, so they have different applications and functions as observing the conversion mechanism, racemization reaction in biological systems, biological probes, acting as antitumor, anti-HIV, antibacterial, antifertility, antimosquito larval, anti-inflammatory, and anticancer, DNA cleaving agents. [4][5][6] Beside biological activities, Schiff bases are also used as dyes, pigments, catalysts, and corrosion inhibitors.…”

“…The antimicrobial investigation established that some of the complexes are very effective toward Gram-positive, Gram-negative bacterial strains, and fungi. Also, Chang, et al [12] prepared three novel complexes, [Cu 4 (L) 4 Cl 4 ]Á H 2 O (1), Zn(L) 2 (2), and Cd(L) 2 (3), and characterized by XRD analyses. All the formed complexes have exceptional antitumor activity toward different cell lines.…”