Effect of the formation of silver nano‐binuclear complex on the refinement of cytotoxic and antibacterial potency of coumarin Schiff base: Spectroscopy, thermal, X‐ray diffraction analyses and density functional theory calculations

Abstract

A new Schiff base (SCH) was prepared using 8‐acetyl‐7‐hydroxy‐4‐methylcoumarin and sulfaclozine. Its silver complex was also synthesized. These compounds were subjected to elemental and spectral analyses. The silver complex was also subjected to thermogravimetric analysis, molar conductance measurements, scanning electron microscopy, energy‐dispersive X‐ray analysis and X‐ray diffraction measurements. The formula of the complex was determined as [(Ag2SCH(NO3)2]. The molar conductance indicates its non‐electrolyte character. The electronic structure and nonlinear optical parameters of SCH and its complex were investigated theoretically at the B3LYP/GENECP level. The geometry of the studied complex is non‐planar as indicated from the dihedral angles between central Ag metal ion and coordinated centres of SCH. Density functional theory calculations were also carried out to calculate the global properties of hardness, global softness and electronegativity. The calculated energy gap between HOMO and LUMO energies shows that charge transfer occurs within the studied complex. The total static dipole moment, the mean polarizability, the anisotropy of the polarizability and the mean first‐order hyperpolarizability were calculated and compared with those of urea as a reference material. The results of the mean first‐order hyperpolarizability showed that SCH and its silver complex are excellent candidates as nonlinear optical materials. The compounds were screened for their antimicrobial effect against various species of bacteria and fungi. Their anticancer activities were evaluated in vitro against the human cancer cell line MCF‐7 (human breast adenocarcinoma).

Silver(I) complexes ofN,N′‐diarylformamidine ligands: Synthesis, crystal structures, and in vitro antibacterial studies

“…[ 7 ] Silver(I) complexes of pyrazolyl s‐triazine were observed to have antimicrobial properties which depended on the nuclearity of the complexes. [ 8 ] An investigation by El‐Ansary et al [ 9 ] showed the enhanced antimicrobial activity of Ag‐coumarin complexes compared with the free ligands, and similar results were also obtained for Ag‐isonicotinic acid complexes. [ 10 ] Interestingly, Ag‐naphthalenol Schiff base complexes showed manifold pharmaceutical therapy, namely, anticancer, antioxidant and antimicrobial offering combination drug treatment at one goal.…”

Theoretical calculations for new coumarin Schiff base complexes as candidates for in vitro and in silico biological applications

“…In a molar ratio of (2:1) (M:L), a proper weight of copper acetate or palladium chloride dissolved in ethanol was mixed with a proper weight of Schiff base, which was prepared and characterized previously. [ 12 ] After adding a few drops of NH 4 OH, about 15 min were given for the complex to condense before being transferred to the reflux system for around 10 h. The complex was then filtered, rinsed with distilled water and hot ethanol, dried, and placed in a desiccator with dry CaCl 2 .…”

“…Several commonly used metal ions, such as copper, zinc, and palladium, are more effective against a variety of diseases. [11] According to El-Ansary et al, [12] the nanosilver complex with coumarin Schiff base (Sb) was studied. In continuation to this work, nanocopper and palladium metal complexes of Schiff base (Sb) in addition to mixed zinc complex of Schiff base (Sb) and ciprofloxacin were synthesized and characterized using a variety of analytical methods in this study.…”

Natural Products–Pyrazine Hybrids: A Review of Developments in Medicinal Chemistry

“…The IC 50 of SCH (104) for the MCF-7 cell line was 90.5 µg/mL, while that of SCH-Ag (105) was 9.3 µg/mL. SCH (104) and SCH-Ag (105) showed less antitumor activity than cisplatin (IC 50 = 1.7 µg/mL) [114].…”