Novel morpholine liganded Pd-based N-heterocyclic carbene complexes: Synthesis, characterization, crystal structure, antidiabetic and anticholinergic properties

Abstract

This study involves the synthesis of novel N-heterocyclic carbene (NHC)PdX2(morpholine) complexes (1a-i). These Pd-based complexes are synthesized from pyridine enhanced precatalyst preparation stabilization and initiation (PEPPSI) complexes and morpholine. The new complexes were characterized by spectroscopy (IR, H-1 and C-13 NMR) techniques. Also, the crystal structures of lb and if were obtained by utilizing the single-crystal X-ray diffraction method. The synthesized compounds in this study were investigated for their inhibition action against equin serum butyrylcholinesterase (BChE) and Electrophorus electricus acetylcholinesterase (AChE) as the capability drug aims for Alzheimer's disease (AD). These novel morpholine liganded Pd-based N-heterocyclic complexes were good inhibitors of BChE, alpha-glycosidase, cytosolic carbonic anhydrase I and II isoforms (hCA I and II), and AChE, with K-i values in the range of 10.77 +/- 1.01-45.86 +/- 5.65 mu M for hCA I, 25.42 +/- 5.18-57.82 +/- 3.01 mu M for hCA II, 12.26 +/- 3.32-50.36 +/- 6.19 mu M for a-glycosidase, 9.97 +/- 1.26-60.75 +/- 15.98 M for BChE, and 10.28 1.55-30.12 3.22 M for AChE. The inhibition of the alpha-glycosidase enzyme, an important carbohydrate hydrolyzing catalyst, could be used as one of the efficient methodologies in both treating and preventing diabetes by controlling the suppressing postprandial hyperglycemia and postprandial glucose amounts. (C) 2018 Elsevier Ltd. All rights reserved.