Macrocyclic copper(II) complexes containing diazacyclam-based ligand: spectral, structural and docking studies

Abstract

The macrocyclic copper complex, [Cu(ACE)(NO3)2]; ACE: 1,3,6,10,12,15hexaazatricyclo[13.3.1.1 6,10 ]eicosane, was synthesized by template condensation from a mixture of N 1-(2-aminoethyl)-1,3-diaminopropane, formaldehyde and copper(II) nitrate. Replacement of the nitrate with thiocyanato and azido ligands gives [Cu(ACE)NSC]NSC (2) and the 1Dcoordination polymer, [Cu(ACE)(μ-N3)]n[N3]n (3), respectively. Complex 1, [Cu(ACE)(NO3)]NO3, is an intermediate product in which one of the nitrate ions is separated from its parent molecule. Formation of 1 allow us to conclude that the mechanism of ion exchange reactions on its parent molecule is similar to SN1. These complexes have been characterized by FT-IR spectroscopy and X-ray crystallography. In the crystal structures of 1 and 2, the copper(II) ion has a distorted square pyramidal geometry in which the N4-donor ACE ligand lies on the equatorial plane and other ligand occupies the axial position. The copper(II) ion in 3 has an octahedral geometry, coordinating to one ACE ligand in the equatorial plane and two N-donor bridging azido groups in the axial positions. In all structures, owing to the Jahn-Teller effect, the coordinated bond length of the axial position is longer than the equatorial ones. The ability of ACE ligand and its complexes 1 and 2, along with their analogues, to interact with ten selected biomacromolecules (BRAF kinase, CatB, DNA gyrase, HDAC7, rHA, RNR, TrxR, TS, Top II, B-DNA) was investigated by docking calculations and compared with that of doxorubicin.

Investigation on the biological activities of an amino alcohol ligand and its salicylaldehyde schiff base along with their copper complexes supported by structural, spectral, theoretical and docking studies

“…Also in octahedral unit, the difference between the axial and equatorial bond length average is 0.697 Å. Based on this observation the zout elongation is con rmed for two complexes units and the elongation down the z-axis is far more dramatic in octahedral geometry than in square pyramidal geometry [31].…”

“…The ligand has no chiral center but after coordination of amine group, its nitrogen atom converts to the chiral atom. Checking the stereochemistry of the polymer revealed that all amines on the one chain have the same enantiomeric form whilst is different than the enantiomeric form of the adjacent chain and lead to a racemic mixture [21,27,31].…”

“…These proteins were selected either due to their reported roles in the cancer growth or as transport agents that affect drug pharmacokinetic properties (e.g., rHA). B-DNA was included to study the possibility of anticancer properties of the compounds [13,30,31].…”

New copper(II) cyclam complexes with aminocarboxylate co-ligands: Synthesis, characterization, and in vitro antiproliferative and antibacterial studies

“…Copper enzymes usually contain metal ions bound to a specific amino acid residue or directly to the amide groupcarbonyl or nitrogenin the peptide backbone, offering different coordination environments. [5][6][7] In the last two decades numerous complexes of transition metals with cyclam were synthesized. Different ways of coordination of macrocycle and its derivatives for different metal cations allows their application as antitumor, antiviral, antibacterial, antifungal or antimalarial agents.…”