Synthetic, structural and antifungal studies of coordination compounds of Ru(III), Rh(III) and Ir(III) with tetradentate schiff bases

Abstract

A series of octahedral Ru(III), Rh(III) and Ir(III) complexes have been prepared with tetradentate Schiff bases derived by condensing isatin with 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,2-diaminobenzene and 1,3-diaminobenzene. The obtained complexes were characterized on the basis of their elemental analyses, magnetic moment, conductance, IR electronic, 1HNMR and FAB mass spectra, as well as thermal analyses. The Ru(III) complexes are low spin paramagnetic, while Rh(III) and Ir(III) behave as diamagnetic complexes. The IR spectral data revealed that all the Schiff bases behave as tetradentate and are coordinated to Ru(III), Rh(III) and Ir(III) via nitrogen and oxygen. Antifungal studies of the ligands as well as their complexes were carried out by the agar plate method.

Isatin‐Schiff base copper(II) complexes—A DFT study of the metal‐ligand bonding situation

“…5). Isosurfaces on column (a) (BPW91-60/TZVP, cutoff 0.003) exhibit, as expected for d 9 configuration, not only positive spin accumulations at the metal centre and ligand atoms directly bonded to the metal centre, but also depletions in the spin density distribution along the Cu(II)-L bonds. Columns (b) and (c) compare the spin-densities distributions calculated by using 60% of HF exchange (BPW91-60) and the gradient-corrected level (BP86) in a cut-off of 0.0007, respectively.…”

“…In addition, different coordination complexes can not only catalyze the generation of hydroxyl radicals through Fenton or Haber-Weiss reactions [7a-c], but also interact with antioxidants, inducing significant cellular oxidative stress, e.g., 1,10-phenanthroline metal complexes, which disrupt mitochondrial function and induce oxidative stress by decreasing of reduced/oxidized glutathione ratios [8a]. Another examples include not only isatin hydrazone derivatives complexes of copper(II), nickel(II), and zinc(II) that presented antitumor activity on human leukemic cells [8b], but also tetradentate isatin complexes of ruthenium(III), iridium(III), and rhodium(III) that have shown antifungal activity, presenting considerable toxicity against Aspergillus niger and Fusarium oxysporium [9].…”

“…The same work suggests that the levels of glutathione in different redox states (GSH and GSSG) are particularly coupled with the verified intracellular uptake of the complexes [10a]. Another important characteristic of isatin-Schiff base copper(II) complexes is that they present a A plethora of experimental studies has focused the chemistry of isatin-Schiff base complexes, investigating the role of transition metals complexes on promoting PCD through oxidative stress process, either by generation of ROS or by inhibition of intracellular antioxidants [8][9][10]. Despite the considerable amount of experimental work reported above, theoretical studies devoted to the investigation of the bonding situation or the mechanism of action of isatin-Schiff base complexes in oxidative process are still lacking in the current literature.…”

Synthesis and spectroscopic characterization of antibacterial rhodium and ruthenium organometallics molded by C–H activation at theorthoposition of a phenyl ring

“…Four bands appeared between 486 and 474 nm, 401 and 399 nm, 346 and 342 nm, and 301 and 299 nm. The lowest energy absorption bands, assigned to 2 T 2g → 4 T 1g and 2 T 2g → 4 T 2g transitions of Ru(III), were observed as shoulders on the charge-transfer band [34]. The electronic spectral assignment suggested octahedral environment around the metal.…”

Rare Earth Complexes: The Search for Quasi-Monochromatic OLEDs

“…Isatin (indole-2, 3 dione) and its derivatives have shown a wide scale of biological activities such as antibacterial 1 , antifungal 2,3 , anticonvulsant 4 , anti-HIV 5 , anticancer and enzyme inhibitors 6 . Isatin is a unique molecule possessing both amide and keto carbonyl groups.…”