Phenoxo-bridged dicopper complexes: Syntheses, characterizations, crystal structures and catecholase activity

Equilibria in Aqueous Cobalt(II)—Reduced Schiff Base N-(2-hydroxybenzyl)alanine System: Chemical Characterization, Kinetic Analysis, Antimicrobial and Cytotoxic Properties

“…They are also popular ligands for antiradical and antioxidant complexes [ 1 , 4 ]. In addition, Schiff base complexes exhibit anti-inflammatory [ 10 ], antibacterial [ 11 , 12 ], antifungal [ 13 ], anticarcinogenic [ 14 , 15 , 16 , 17 , 18 ], catecholase [ 19 , 20 ] activities and DNA-binding ability [ 21 , 22 ].…”

“…The present study examines the complexation equilibria in the aqueous system of cobalt(II) with the reduced Schiff base N -(2-hydroxybenzyl)alanine, AlaSal ( Figure 1 ), obtained as a result of a reaction between salicylaldehyde and L-alanine, followed by reduction. The formation of specific complex structures is strongly influenced by the nature of the ligands, the pH of the solution, the nature of solvents used, and the concentration of dioxygen in solution [ 20 ]. Therefore, in the initial stage of biological research into such compounds, it is necessary to determine the effect of pH on the types of complexes formed, and then their stability in aqueous solution.…”

Ancillary-Ligand-Assisted Variation in Nuclearities Leading to the Formation of Di-, Tri-, and Tetranuclear Copper(II) Complexes with Multifaceted Carboxylate Coordination Chemistry

“…The broad d–d absorption bands, with maxima at 686 nm (ε = 281 M –1 cm –1 ), 725 nm (ε = 122 M –1 cm –1 ), and 729 nm (ε = 95 M –1 cm –1 ) for 1 – 3 , respectively, are induced by the Hcpdp 2– /cpdp 3– ligand. These d–d transitions are consistent with copper(II) ions coordinated by oxygen and nitrogen donor atoms of the ligands. − The intense absorptions bands at 260 nm (ε = 3189 M –1 cm –1 ) and 230 nm (ε = 7307 M –1 cm –1 ), 259 nm (ε = 10060 M –1 cm –1 ) and 230 nm (ε = 11354 M –1 cm –1 ), and 263 nm (ε = 7856 M –1 cm –1 ) sh and 230 nm (ε = 11878 M –1 cm –1 ) are dominated by copper(II) ion-bound intraligand π–π* transitions for 1 – 3 , respectively. For comparison, the UV–vis spectrum of the free ligand H 3 cpdp in MeOH has been included, which exhibits three very strong absorption bands at 254 nm (ε = 218835 M –1 cm –1 ) sh , 261 nm (ε = 240441 M –1 cm –1 ), and 268 nm (ε = 182728 M –1 cm –1 ) sh in the charge-transfer region (Figure S12 of the Supporting Information).…”