Silver N‐heterocyclic carbene complexes bearing fluorinated benzyl group: Synthesis, characterization, crystal structure, computational studies, and inhibitory properties against some metabolic enzymes

Abstract

A series of the silver N‐heterocyclic carbene (NHC) complexes have been synthesized from the reactions between benzimidazolium salts bearing fluorinated benzyl group and Ag2O via the deprotonation method. All Ag(I)NHC complexes were characterized by known spectroscopic techniques (1H nuclear magnetic resonance [NMR], 13C NMR, and Fourier transform infrared [FT‐IR]) and elemental analysis. The molecular structures of the two complexes were unambiguously elucidated through single‐crystal X‐ray diffraction analysis. Namely, X‐ray studies show that the coordination geometry around the Ag(I) atom in the case of complex 2c is revealed to be almost linear with C–Ag–Cl angle, whereas in complex 2e, it appears as a nonlinear structure. The inhibitory profiles of these new complexes are investigated on some metabolic enzymes. Representatively, the most potent complex against human carbonic anhydrase isoenzymes I and II (hCAs I and II), 2d, was 1.8 times more potent than standard inhibitor acetazolamide against hCAs I and II. On the other hand, complexes 2c and 2b as most potent compounds against both cholinesterase enzymes was around 5 and 1.6 times more potent than tacrine against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), respectively. The most active α‐glucosidase inhibitor 2d had similar activity to acarbose as a standard inhibitor. Furthermore, it confirms its in vitro studies as a result of molecular docking studies for each enzyme with (i) binding energy and inhibition constant values and (ii) the definition of the best conformation and nonbonding interactions of the related complexes (2b, 2c, and 2d) against the different target proteins.

Polyphenol Contents, Potential Antioxidant, Anticholinergic and Antidiabetic Properties of Mountain Mint (Cyclotrichium leucotrichum)

“…One α-glycosidase unit is the quantity of enzyme, which catalyzes the hydrolysis of 1.0 mol p-NPG per minute at pH 7.4. [63] 4.8.3. α-Amylase Inhibition Studies α-Amylase inhibitory effects of MECL and WECL was realized according to the procedure of Xiao. [64] using starch as substrate.…”

“…One α-amylase unit is defined as the quantity of α-amylase required to release 1 μmol of reducing sugar estimated as glucose per min (pH 6.9, 40 °C). [63]…”

Synthesis and biological evaluation of Au‐NHC complexes

“…[ 63–67 ] No exceptional values are found for the bond lengths and angles in the benzimidazole ring for both complexes, and these values agree well with those reported for carbene complexes. [ 63,65,68–70 ]…”

Screening of Carbonic Anhydrase, Acetylcholinesterase, Butyrylcholinesterase, and α-Glycosidase Enzyme Inhibition Effects and Antioxidant Activity of Coumestrol

“…The sample was applied to the affinity column and equilibrated with Tris-Na 2 SO 4 /HCl (22 mM/25 mM, pH: 8.7). Finally, the hCA II isozyme was eluted with sodium acetate/NaClO 4 (0.5 M, pH 5.6, 25 °C) [ 101 ]. The protein content during the purification steps was determined via the Bradford method [ 102 ].…”