Density functional theory molecular modelling, DNA interactions, antioxidant, antimicrobial, anticancer and biothermodynamic studies of bioactive water soluble mixed ligand complexes

Abstract

A novel series of bioactive water soluble mixed ligand complexes (1-5) [M(L)(phen)AcO]. nHO {where M = Cu (1) n = 2; Co (2), Mn (3), Ni (4), n = 4 and Zn (5) n = 2} were synthesized from 2-(2-Morpholinoethylimino) methyl)phenol Schiff base ligand (LH), 1, 10-phenanthroline and metal(II) acetate salt in a 1:1:1 stoichiometric ratio and characterized by several spectral techniques. The obtained analytical and spectral data suggest the octahedral geometry around the central metal ion. Density functional theory calculations have been further supportive to explore the optimized structure and chemical reactivity of these complexes from their frontier molecular orbitals. Gel electrophoresis result indicates that complex (1) manifested an excellent DNA cleavage property than others. The observed binding constants with free energy changes by electronic absorption technique and DNA binding affinity values by viscosity measurements for all compounds were found in the following order (1) > (2) > (4) > (5) > (3) > (LH). The binding results and thermodynamic parameters are described the intercalation mode. In vitro antioxidant properties disclose that complex (1) divulges high scavenging activity against DPPH, OH, O NO, and Fe. The antimicrobial reports illustrate that the complexes (1-5) were exhibited well defined inhibitory effect than ligand (LH) against the selected different pathogenic species. The observed percentage growth inhibition against A549, HepG2, MCF-7, and NHDF cell lines suggest that complex (1) has exhibited superior anticancer potency than others. Thus, the complex (1) may contribute as potential anticancer agent due to its unique interaction mode with DNA.GRAPHICAL ABSTRACT[Formula: see text] Communicated by Ramaswamy H. Sarma.

Spectro-electrochemical assessments of DNA/BSA interactions, cytotoxicity, radical scavenging and pharmacological implications of biosensitive and biologically active morpholine-based metal(ii) complexes: a combined experimental and computational investigation

“…Moreover, Ross and coworkers reported that the enthalpy changes (DH ) and entropy changes (DS ) occurred in the following order: (a) hydrophobic forces / DH > 0 and DS > 0, (b) van der Waals interaction and hydrogen bonding / DH < 0 and DS < 0, (c) electrostatic interactions / H < 0 or DH z 0 and DS > 0. 21,52 The observed results DH < 0 and DS < 0 clearly described that the interactions between complexes (1-5) and DNA could be attributed to van der Waals forces and hydrogen bonding. However, the loss of translational and rotational degrees of freedom and the interaction of counter ions along with hydrophobic forces in the complex-DNA adduct could provide for negative entropy and enthalpy changes with an exothermic effect.…”

“…More detail are given in our previous report. 21 Synthesis of the Schiff base ligand (HL) and its complexes (1)(2)(3)(4)(5) Details of the synthesized ligand (HL) and its complexes (1)(2)(3)(4)(5) together with information from the various structural characterization studies are enclosed in the ESI † (Scheme 1).…”

“…† The antioxidant studies for DPPH, hydroxyl, superoxide, nitric oxide radical scavenging and ferric reducing antioxidant power (FRAP) assay were carried out with careful monitoring of the absorbance at 517, 230, 590, 546 and 700 nm, respectively. 21 In vitro antimicrobial assay. Antimicrobial activities of all the compounds were screened against seven selected different pathogenic bacteria and three different fungi species by the Kirby-Bauer agar disc diffusion method 36 (Table 6).…”

“…The obtained results (mean OD AE SD) from triplicate wells were used in the calculations to determine the half-maximum inhibitory concentration (IC 50 ) by means of the percentage cell viability/growth inhibition of the test samples and the results were compared with the standard anticancer drug (cisplatin). 21,38 Results and discussions…”

Microwave assisted synthesis and antimicrobial evaluation of symmetrical 1,2-Phenylenediamine Schiff’s base derivatives

“…[8][9][10] Furthermore, the metal complexes of Schiff compounds have been of main attention for a lengthy time due to their capability to join oxygen to redox systems 11 that are oxidizing DNA. 12 They showed noteworthy antimicrobial activity owing to the free radical scavenging capability of their metal composites. Many research groups have been concerned in the chemical synthesis and biological testing of Schiff bases.…”