Bioorganic chemistry | 2019
Novel 2-aminopyridine liganded Pd(II) N-heterocyclic carbene complexes: Synthesis, characterization, crystal structure and bioactivity properties.
Abstract
In this work, the synthesis, crystal structure, characterization, and enzyme inhibition effects of the novel a series of 2-aminopyridine liganded Pd(II) N-heterocyclic carbene (NHC) complexes were examined. These complexes of the Pd-based were synthesized from PEPPSI complexes and 2-aminopyridine. The novel complexes were characterized by using 13C NMR, 1H NMR, elemental analysis, and FTIR spectroscopy techniques. Also, crystal structures of the two compounds were recorded by using single-crystal X-ray diffraction assay. Also, these complexes were tested toward some metabolic enzymes like α-glycosidase, aldose reductase, butyrylcholinesterase, acetylcholinesterase enzymes, and carbonic anhydrase I, and II isoforms. The novel 2-aminopyridine liganded (NHC)PdI2(2-aminopyridine) complexes (1a-i) showed Ki values of in range of 5.78\u202f±\u202f0.33-22.51\u202f±\u202f8.59\u202fnM against hCA I, 13.77\u202f±\u202f2.21-30.81\u202f±\u202f4.87\u202fnM against hCA II, 0.44\u202f±\u202f0.08-1.87\u202f±\u202f0.11\u202fnM against AChE and 3.25\u202f±\u202f0.34-12.89\u202f±\u202f4.77\u202fnM against BChE. Additionally, we studied the inhibition effect of these derivatives on aldose reductase and α-glycosidase enzymes. For these compounds, compound 1d showed maximum inhibition effect against AR with a Ki value of 360.37\u202f±\u202f55.82\u202fnM. Finally, all compounds were tested for the inhibition of α-glycosidase enzyme, which recorded efficient inhibition profiles with Ki values in the range of 4.44\u202f±\u202f0.65-12.67\u202f±\u202f2.50\u202fnM against α-glycosidase.