Tetrakis(1H-benzimidazole-κN³)(nitrato-κO)copper(II) nitrate

Abstract

In the title salt, [Cu(NO3)(C7H6N2)4]NO3, one nitrate anion is coordinated to the CuII atom, which is also coordinated by the N atoms of four N-heterocycles. The geometry at the metal atom is a square pyramid in which the O atom of the anion occupies the apical position [Cu—O = 2.468 (5) and 2.590 (7) Å in the two independent formula units]. The cation lies on a twofold rotation axis; the coordinated nitrate anion is also disordered about this symmetry element. The lattice anion is also disordered about a twofold rotation axis. In the crystal, the cations are linked to the coordinated and free anions by N—H⋯O hydrogen bonds.

Preparation of Two Maleic Acid Sulfonamide Salts and Their Copper(II) Complexes and Antiglaucoma Activity Studies

“…[10][11][12] One of the methods used in glaucoma treatment is to reduce the production of aqueous humor 10,13 by using carbonic anhydrase inhibitors. 4,5,11,13,14 2-Aminopyridines and benzimidazoles serve as useful chelating ligands in a variety of inorganic and organometallic applications, [15][16][17] and also act as monodentate ligands which coordinate the metal ions through the nitrogen of the ring [16][17][18][19][20][21] in most cases. In addition, there are several works on 2-aminopyridine complexes in which the amino group also participates in coordination.…”

“…22,23 The chemistry of copper(II) carboxylate complexes with N-donor ligands especially with AP (2-animopyridine, 5) and BI (1H-benzimidazole, 8) has been extensively studied over the past few decades. 16,[18][19][20][21] Two types of ligands, generally acids (e.g., carboxylic acids) and bases, e.g., AP or BI, are brought together before coordination to the metal ion in order to prepare the mixed ligand complex compounds. 18,[24][25][26] The metal complexes with mixed ligands have shown better biological activities than the simple ones.…”