New morpholine-liganded palladium(II) N-heterocyclic carbene complexes: Synthesis, characterization, crystal structure, and DNA-binding studies

Arch Pharm (Weinheim). 2019 Dec;352(12):e1900187. doi: 10.1002/ardp.201900187. Epub 2019 Oct 4.

Abstract

A series of the morpholine-liganded palladium(II) complexes (1a-e) bearing N-heterocyclic carbene (NHC) functionalized by benzonitrile were synthesized. These complexes were synthesized from (NHC)Pd(II)(pyridine) complexes (PEPPSI) and morpholine. The new complexes were fully characterized by using 1 H NMR, 13 C NMR, Fourier-transform infrared spectroscopy, and elemental analysis techniques. Single-crystal X-ray diffraction was used to determine the structure of a derivative. The DNA-binding studies of the new (NHC)Pd(II)morpholine complexes were examined using the pBR322 plasmid. The 2,4,6-trimethylbenzyl derivative compound has the most DNA binding activity. In addition, for the 3-methylbenzyl derivative compound, oxidation effects were observed at concentrations higher than 100 µg/ml. Also, the molecular and crystal structures of the complex 3-methylbenzyl derivative compound were recorded by using a single-crystal X-ray diffraction method.

Keywords: DNA binding; N-heterocyclic carbene; structure elucidation; substituent effect; synthesis.

MeSH terms

  • Binding Sites
  • Coordination Complexes / chemical synthesis*
  • Coordination Complexes / chemistry
  • Coordination Complexes / pharmacology
  • Crystallography, X-Ray
  • DNA, Circular / chemistry
  • Ligands
  • Methane / analogs & derivatives*
  • Methane / chemistry
  • Morpholines / chemical synthesis*
  • Morpholines / chemistry
  • Morpholines / pharmacology
  • Nitriles / chemistry
  • Palladium / chemistry*
  • Plasmids / chemistry

Substances

  • Coordination Complexes
  • DNA, Circular
  • Ligands
  • Morpholines
  • Nitriles
  • carbene
  • Palladium
  • benzonitrile
  • Methane