Aminoguanidine Bicarbonate Research Articles

Aminoguanidinium hydrogen 1,1-cyclobutane dicarboxylate: Synthesis, structural characterization and molecular docking studies

On neutralization of Aminoguanidine bicarbonate (H2Agun) with 1,1 -cyclobutane dicarboxylic acid (H2CBD) resulted aminoguanidinium salt, [(HAgun)+(HCBD)-]. Using FT-IR, 1H NMR, 13C NMR, and analytical spectroscopy, the compound was identified and characterized. Furthermore, single X-ray diffraction experiment confirms the molecular structure of the salt. The molecular docking approach has been employed to investigate the inhibitory properties of aminoguanidinium hydrogen 1,1-cyclobutane dicarboxylate on three key cancer protein receptors: 3WZE (VEGFR kinase), 5ZMA (crystal structure of an allosteric Eya2 phosphates inhibitor lung cancer protein), and 1JNX (BRCT repeat region from the breast cancer associated protein). Observation of lower binding energy of −4.67 kcal/mol for 3WZE, −4.57 kcal/mol for 5ZMA and 1.7 kcal/mol for 1JNX, respectively, indicating high stability with the protein molecule.

Microwave-Assisted Synthesis of 5-Substituted 3-Amino-1,2,4-triazoles from Aminoguanidine Bicarbonate and Carboxylic Acids

The effect of the molar ratio between reagents, reaction time and temperature on the yield of 5-substituted 3-amino-1,2,4-triazoles obtained by the direct condensation of carboxylic acids with aminoguanidine bicarbonate under acid catalysis conditions was studied. As a result, a general green straightforward synthesis of the title compounds bearing aliphatic substituents or a phenyl ring was developed using sealed reaction vials under controlled microwave synthesis conditions that are suitable for the application of volatile starting carboxylic acids. Our straightforward synthetic method proposed in this work increases the synthetic accessibility of these widely used building blocks and therefore is able to significantly expand the structural diversity of compounds containing a triazole moiety for the needs of drug discovery.

Facile and green synthesis, crystal structure, antibacterial activity, Hirshfeld surface analysis, and computational investigation of a novel lithium(I) complex: Comparisons of theoretical and experimental analyses

A novel monovalent lithium complex, [Li(C6H4NO3)(H2O)2] (1), was prepared via a simple one-pot green reaction of 2-hydroxypyridine-3-carboxylic acid (2-hpca) with lithium carbonate and aminoguanidine (Amgu) bicarbonate in water. Complex 1 was investigated using elemental, ultraviolet–visible, Fourier transform infrared (FT-IR), thermal, and single-crystal X-ray diffraction (SC-XRD) measurements. We found that 1 crystallized in the monoclinic C2/m space group with a = 12.800(2) Å, b = 6.6657(13) Å, and c = 9.4687(19) Å. The Li ion exhibited four coordinates with a distorted square planar geometry. That is, the ion was surrounded by four oxygen atoms, of which two were derived from two water molecules, one was from the carboxylate group, and one was from the keto group of the 2-oxo-1,2-dihydropyridine-3-carboxylate ligand. Simultaneous thermogravimetry–differential thermal analysis of 1 exhibited dehydration followed by continuous low-temperature (∼400 °C) decomposition to produce lithium oxide as the end product in an air atmosphere. Furthermore, density functional theory (DFT) analysis was conducted to compare the theoretical and experimental data collected via SC-XRD. In addition, DFT was used to analyze the frontier molecular orbital energy levels and energy gaps. Moreover, we conducted Hirshfeld surface studies with respect to 1 to differentiate between the intermolecular hydrogen bond contacts. Energy frameworks for 1 were produced by analyzing the energy interactions between intermolecular hydrogen bonds to investigate the prevailing interactions involved in molecular packing. The in silico results showed that 1 has high potential for the development of antimicrobial drugs. Molecular docking studies were also conducted to determine the binding energy of 1 with Staphylococcus aureus (5CZZ) and Escherichia coli (3T88). The results were consistent with the experimental data obtained from the antibacterial activity of 1 with respect to Staphylococcus aureus and Escherichia coli.

Synthesis, Characterisation, Theoretical NMR Calculations and Crystal Structure of the 3-methyl-1H-1,2,4?4-triazole-5-amine acetate

The condensation reaction between aminoguanidine bicarbonate with carboxylic acids led to the formation of 3-methyl-1H-1,2,4-triazole-5-amine (mta), 3-methyl-1H-1,2,4l4-triazole-5-amine acetate (Hmta) and 3-phenyl-1H-1,2,4-triazole-5-amine (pta). The compound N-(3-methyl-1H-1,2,4-triazole-5-yl)propan-2-imine (mpta) was obtained by reacting the mta with acetone, upon an attempt of purifying mta in this solvent. The excess of acetic acid obtained the Hmta during the preparation of mta. These compounds were characterised by infrared and multinuclear NMR (1H and 13C) spectroscopy, microanalysis, and melting point. To investigate the formation of possible tautomeric conformations of mta, pta and mpta in solution, a theoretical approach was used to calculate the chemical shifts of carbon 13, based on the values of magnetic shielding tensor (NMR) by MPn and DFT methods. The biological assay of the triazoles mta, pta and mpta against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Salmonella typhimurium showed no activity at the highest concentration used in the experiment.

New Guanidinium and Aminoguanidinim Salts of 2-Hydroxypyridine-3-carboxylic acid: Preparation and spectral, structural, thermal, ADMET, biological, and molecular docking studies

The reaction of guanidine carbonate and aminoguanidine bicarbonate with 2-hydroxypyridine-3-carboxylic acid in various mole ratios (1:1, 1:2, and 2:1) resulted in the formation of the salts [GunH][C6H4NO3]▪H2O (1), [GunH][C12H9N2O6] ▪H2O (2), [GunH]2[C6H3NO3]▪H2O (3), [AmguH][C6H4NO3]▪H2O (4), [AmguH][C12H9N2O6] (5), and [AmguH]2[C6H3NO3]▪H2O (6) [where GunH+- guanidinium (+1) and AmguH+- aminoguanidinium (+1) salts]. Elemental analysis, FT-IR, 1H NMR, and TG-DTA studies were used to identify and characterize the synthesized simple salts. All compounds were polycrystalline in nature, except (1), which was obtained as single crystal. Single-crystal X-ray diffraction studies confirmed the structure of (1), which crystallizes in a monoclinic system with the P21/n space group, with molecular formula C7H12N4O4. FT-IR spectra of the aminoguanidinium salts reveal NN stretching frequencies in the range of 989–914 cm−1, indicating the presence of aminoguanidinium moiety. The NH2 protons of the guanidinium/aminoguanidinium moiety are assigned to the 7–7.5 δ signals in the 1H NMR signals for the simple salts (1)–(6). The thermal reactivity and stability of the as-prepared salts were investigated in air using simultaneous TG-DTA analysis. Except for compounds (5) and (6), the TG-DTA of all the salts showed dehydration followed by continuous decomposition to produce gaseous products. All the salts underwent endothermic decomposition followed by exothermic combustion in the temperatures range from 120 to 450 °C. Furthermore, the salts have appreciable drug-likeness characters according to Lipinski's regulations, as predicted by the in silico ADMET properties. Molecular docking studies of salts also revealed good binding affinity toward 3MIW, 4WM8, and 5IBV proteins. Among the six salts prepared, the diguanidinium salts showed good anticancer activity against human lung adenocarcinoma and human breast adenocarcinoma cell lines. The disk diffusion method was adopted to investigate the antibacterial activities of compounds (1)–(6) in vitro against two bacterial strains. All the salts displayed potential antibacterial activity against Escherichia coli and Staphylococcus aureus.

ADP-ribosyl transferase activity and gamma radiation cytotoxicity of Pseudomonas aeruginosa exotoxin A

This work explores the ADP-ribosyltransferase activity of Pseudomonas (P.) aeruginosa exotoxin A using the guanyl hydrazone derivative, nitrobenzylidine aminoguanidine (NBAG) and the impact of gamma radiation on its efficacy. Unlike the conventional detection methods, NBAG was used as the acceptor of ADP ribose moiety instead of wheat germ extract elongation factor 2. Exotoxin A was extracted from P. aeruginosa clinical isolates and screened for toxA gene using standard PCR. NBAG was synthesized using aminoguanidine bicarbonate and 4-nitrobenzaldehyde and its identity has been confirmed by UV, FTIR, Mass and 13C-NMR spectroscopy. The ADP-ribosyl transferase activity of exotoxin A on NBAG in the presence of Nicotinamide adenine dinucleotide (NAD+) was recorded using UV spectroscopy and HPLC. In vitro ADP-ribosyl transferase activity of exotoxin A protein extract was also explored by monitoring its cytotoxicity on Hep-2 cells using sulforhodamine B cytotoxicity assay. Bacterial broths were irradiated at 5, 10, 15, 24 Gy and exotoxin A protein extract activity were assessed post exposure. Exotoxin A extract exerted an ADP-ribosyltransferase ability which was depicted by the appearance of a new ʎmax after the addition of exotoxin A to NBAG/NAD+ mixture, fragmentation of NAD+ and development of new peaks in HPLC chromatograms. Intracellular enzyme activity was confirmed by the prominent cytotoxic effects of exotoxin A extract on cultured cells. In conclusion, the activity of Exotoxin A can be monitored via its ADP-ribosyltransferase activity and low doses of gamma radiation reduced its activity. Therefore, coupling radiotherapy with exotoxin A in cancer therapy should be carefully monitored.

Structural and multi-functional properties of novel thorium complex bearing higher analogue of guanidine base

New-fangled water mediated and air stable thorium complex of molecular formula (AgunH)2[Th(dip)3].H2O have been prepared by reacting thorium(IV) nitrate, dipicolinic acid (H2dip) and aminoguanidine bicarbonate (AgunH.HCO3) at appropriate molar ratio via., template method. The complex has been systematically characterized by chemical analysis, elemental, spectral, thermal and single crystal studies including luminescence and antioxidant properties. The IR spectrum of the resulting complex infers that the carboxylate anion behaves as a monodentate and facilitates to form a monomeric rather than polymeric environment. This is further confirmed by single crystal X-ray diffraction studies. Thermal stability of the title compound undergoes step-wise decomposition to endure ThO(CO3) as the end residue. The single crystal X-ray study reveals that the thorium complex crystallizes in the triclinic crystal system with centric space group (P-1) of Z = 2. Each dipicolinate anion (dip2−) exhibits tridentate coordination modes through a nitrogen atom of pyridine ring and oxygen atoms of the carboxylate groups to form nine coordination with tri-capped trigonal prismatic geometry. Further, the anionic complex is neutralized by two aminoguanidinium (AgunH+) cations and stabilized along with a lattice water molecule. This material shows enhanced luminescent properties, this is due to the crucial role of dipicolinate anion not for aminoguanidinium moiety. Whereas, the aminoguanidinium species is promote to act as a secondary antioxidant.

High Thermal Stability and Insensitive Fused Triazole-Triazine Trifluoromethyl-Containing Explosives (TFX).

A trifluoromethyl-containing fused triazole-triazine energetic molecule, 3-nitro-7-(trifluoromethyl)-1,2,4-triazolo[5,1-c]-1,2,4-triazin-4-amine (TFX), has been synthesized in three steps from amino guanidine bicarbonate and trifluoroacetic acid. The process was found to be effective, nontoxic, and simple. The X-ray structure analysis of TFX finds that there are inter- and intramolecular hydrogen bonds and π–π interactions in the crystal lattice. TFX with a high density (1.88 g·cm–3) at room temperature, excellent thermal stability (Tp = 300.3 °C), moderate energetic performance, and with insensitivity to mechanical stimulation has potential as heat-resistant energetic materials.

Structural and antioxidant properties of guanylhydrazinium pyrazine-2-carboxylate

In general, molecules with certain functional groups such as amine (-NH2) and carboxyl (-COOH) can promote the growth of co-crystals leading to the formation of supramolecular networks. However, if the differences in the pKa values of the two molecules are large [pKa (base)—pKa (acid)], salts can result instead of ‘real’ co-crystals. Here, we report the formation of such salt by letting pyrazine-2-carboxylic acid (pKa = 2.9) crystallize together with aminoguanidine (pKa = 11.5; high Δpka = 8.6) a nitrogen-rich organic base. The title salt has been prepared by slow evaporation of an equimolar ratio of guanylhydrazine bicarbonate (i.e., aminoguanidine bicarbonate (AgunH.HCO3)) and pyrazine-2-carboxylic acid (Pymca) in aqueous medium. The salt was characterized by IR spectroscopy, powder and single-crystal X-ray diffraction techniques. This material shows enhanced antioxidant activity and this is due to the crucial role of hydrazinic moiety in the aminoguanidinium salt.

PARTICIPATION OF INOS IN THE EFFECT OF IL-1β ON LUNG VENTILATION AND HYPOXIC CHEMORECEPTION

With systemic inflammation, hypoxia, and an increase in the respiratory, a significant increase in the systemic level of pro-inflammatory cytokines is observed. Recently we demonstrated that elevated IL-1β level in blood reduces the ventilatory response to hypoxia. The aim of the present study was to examine the hypothesis that the respiratory effect of IL-1β may be mediating the NO-dependent mechanisms.The experiments were performed on anaesthetized rats. We studied the effects of intravenous administration of cytokine during inhibition of iNO-synthase. In order to we used aminoguanidine bicarbonate - specific inhibitor of iNOS, which was injected in the tail vein for 30 minutes before the administration of cytokine. During the hypoxic rebreathing experiments, was found that the increase of IL-1β level in blood weakens the respiratory response to hypoxia. The ventilatory, tidal volume and mean inspiratory flow responses decreased by 29%, 31% and 53% respectively. INO-synthase inhibitor pretreatment eliminated these respiratory effects of IL-1β. Thus the data indicate that the ability of IL-1β to reduce the ventilatory hypoxic response is mediated by the NO-dependent pathway.

Trifluoromethyl–containing 1,2,4-triazines. Synthesis on the base of perfluorobiacetyl and reactions with thiosemicarbazide and thiourea

Cis-, trans-isomers of 5,6-dihydroxy-5,6-bis(trifluoromethyl)- [1,2,4]-triazinan-3-thione (yield ˜69%), 5-hydroxy-5,6-bis(trifluoromethyl)-4,5-dihydro-2H- [1,2,4]-triazine-3-thione(one) (yield ˜75 − 81%) and 5,6-bis(trifluoromethyl)-1,2,4-triazine-3-amine (yield ˜60%) were synthesized by the reaction of perfluorobiacetyl with thiosemicarbazide, semicarbazide hydrochloride and aminoguanidine bicarbonate. Treating the synthesized 3-thioxo(oxo)-1,2,4-triazines with thiosemicarbazide, thiourea and hydrazine dihydrochloride gave the reduction products − 5,6-bis(trifluoromethyl)-4,5-dihydro-2H- [1,2,4]-triazine-3-thione (yield 14 − 52%) and 5,6-bis(trifluoromethyl)-4,5-dihydro-2H- [1,2,4]-triazine-3-one (yield 20–23%). The reactions with thiosemicarbazide and thiourea was accompanied by the formation of unexpected products − 5-thioxo-3a,6a-bis(trifluoromethyl)hexahydro-2H-imidazo[4,5-d]-1,3-thiazol-2-one and 5,6-bis(trifluoromethyl)-1,2,4-triazine-3-amine. The reaction of 5,6-dihydroxy-5,6-bis(trifluoromethyl)-imidazolidine-2-thione and the synthesized 3-thioxo(oxo)-1,2,4-triazines with aminoguanidine bicarbonate gives 5,6-bis(trifluoromethyl)-1,2,4-triazine-3-amine (yield ˜35 − 47%) and also can be used as a method for its preparation.

Synthesis and Investigation of 2,3,5,6-Tetra-(1H-tetrazol-5-yl)pyrazine Based Energetic Materials.

The structures and properties of several energetic compounds based on a high-nitrogen-content anion, namely 2,3,5,6-tetra(1H-tetrazol-5-yl)pyrazine (H4 TTP) are reported here for the first time. These energetic salts were synthesized by reacting H4 TTP with various alkali metal hydroxides (sodium, potassium, rubidium, caesium) and N-based (ammonia, hydrazine, hydroxylamine, guanidine carbonate, aminoguanidine bicarbonate). The resulting materials were comprehensively characterized by multinuclear (1 H, 13 C) NMR spectroscopy, infrared spectroscopy, elemental analysis, DSC, as well as low-temperature single-crystal X-ray diffraction. Heats of formation for the metal-free species as well as detonation parameters were calculated. The presented energetic materials (EMs) show high thermal stability (207 °C≤Tdec ≤300 °C), while the metal-free ionic derivatives exhibit desirable properties such as detonation velocity (6873 m s-1 ≤VC-J ≤8364 m s-1 ), detonation pressure (14.3 GPa≤pC-J ≤24.9 GPa), and specific impulse (141.4≤Isp ≤192.5 s).

Structural resemblance and variation in transition metal complexes derived from dipicolinic acid and guanylhydrazine

New aminoguanidinium transition metal dipicolinates of the formula (AgunH)[MIII(dip)2]·xH2O, M = Cr, x = 1.5; Fe, x = 2, (AgunH)2[MII(dip)2]·nH2O, where M = Mn, n = 2; Co or Ni, n = 0 and Zn, n = 1, and [Cu(Agun)2][Cu3(dip)4(Agun)2]·4H2O have been prepared by the reaction of respective metal nitrates with aqueous mixture of dipicolinic acid (H2dip) and aminoguanidine bicarbonate (AgunH·HCO3) in appropriate mole ratios. These compounds have been characterized by various physico-chemical techniques. Among them Ni, Cu, Cr and Fe complexes have been structurally characterized. The asymmetric units of the Ni and Cr structures contain two independent molecules, whereas Fe has four. Unlike these, the copper compound has a unique structure with a tri-nuclear centrosymmetric anionic complex and cationic bis(aminoguanidine)copper(II). In all of these compounds, the dipicolinate dianion is acting as a tridentate (O,N,O) donor ligand, except copper in-which one of the dipicolinates is tetradentate (O,N,O,O). Cytotoxicity and DPPH scavenging activity studies reveal that the copper complex exhibits superior activity to that of cobalt and nickel.

Synthesis and Investigation of 2,6-Bis(picrylamino)-3,5-dinitro-pyridine (PYX) and Its Salts.

2,6-Bis(picrylamino)pyridine (1; pre-PYX) and 2,6-bis(picrylamino)-3,5-dinitropyridine (2; PYX) were synthesized using an improved literature method. Compounds 1 and 2 were reinvestigated in detail and the X-ray structures (1: ρ=1.698 g cm(-3) at 173 K; 2: ρ=1.757 g cm(-3) at 298 K) are given. The reactions of 2 with different bases, such as alkali metal hydroxides (sodium, potassium, rubidium, cesium), and N-bases (ammonia, hydrazine, hydroxylamine, guanidinium carbonate, aminoguanidine bicarbonate) are reported, as well as metathesis reactions producing energetic salts. Several energetic compounds were synthesized and characterized for the first time using vibrational (IR, Raman) and multinuclear NMR spectroscopy, mass spectrometry, elemental analysis, and DSC. The crystal structures of four energetic salts were determined using low temperature single-crystal X-ray diffraction. Heats of formation for the metal-free species were calculated using the Gaussian 09 software. Detonation parameters were estimated using the EXPLO5 program. The sensitivities towards impact, friction, and electrostatic discharge were also determined.

The chemistry of aminoguanidine derivatives – preparation, crystal structure, thermal properties, and molecular docking studies of aminoguanidinium salts of several carboxylic acids

The reaction of aminoguanidine bicarbonate (Amg) with oxamic, oxalic, malonic and sulfoacetic acids yielded (AmgH)H2NOC–COO (1), OOC–CONHNHC(NH2)NH2 (2) (AmgH)HOOC–CH2–COO (3) and O3S–CH2–CONHNHC(NH2)NH2 (4), respectively. For the first time, we studied the salt-forming ability of aminoguanidine with several carboxylic acids, such as oxamic, oxalic, malonic and sulphoacetic acids. We also compared the structural and thermal properties of these salts. Oxamic and malonic acids form only mono-aminoguanidinium salts, whereas oxalic acid mainly forms di-aminoguanidinium oxalate. In addition, oxalic acid forms guanylhydrazido-oxalic acid which exists as zwitter ion. Unlike other acids, sulfoacetic acid readily forms only the zwitter ionic salts (2-guanylhydrazido-oxo-methanesulfonic acid) rather than the usual simple salt. This result may be a result of the highly acidic nature of the sulfonic group, which favors acid catalyzed condensation. More significantly, for the first time, the ability guanylhydrazido-oxalic acid (2) and 2-guanylhydrazido-oxo-methanesulfonic acid (4) to inhibit human butyrylcholinesterase (human BChE) receptor has been studied with a molecular docking approach. The binding of the compounds to human BChE was examined as it is crucial to understanding the biological significance of aminoguanidine derivatives. The compounds were identified and characterized by analytical, FT-IR spectroscopic and thermal studies. Furthermore, the structures of compounds 1, 2 and 4 were confirmed by single X-ray diffraction studies. Compounds 1 and 2 crystallized in a monoclinic crystal system with P21/c and Cc space groups, respectively, whereas compound 4 crystalized in an orthorhombic system with a Pbca space group. All the compounds (1–4) underwent endo- followed by exothermic decomposition in the temperature range from 130 to 600°C to yield gaseous products.

Непептидные ингибиторы фурина на основе амидиногидразонов диарилальдегидов

A series of novel non-peptidic furin inhibitors containing amidinohydrazone moieties has been synthesized under interaction of dialdehydes, the derivatives of ethylene diethylvanillin ethers, with aminoguanidine bicarbonate. Two aryl cycles were bridged by 1,2-ethylene-, 1,4-buthylene- or 1,4-dimethylenebenzene-group. The compounds have been found to inhibit furin. The antifurin activity was shown to grow with the increase of the length and/or hydrophobicity of the bridge. The most potent compound, containing in the bridge the lypophylic benzene cycle was found to inhibit the activity of furin with Ki = 0.51 microM.

Effect of aminoguanidine and copper(II) ions on the formation of advanced glycosylation end products. In vitro study on human serum albumin.

Nonenzymatic glycosylation of proteins is a weighty consequence of hyperglycaemia in diabetes. This study examines the possible effect of copper(II) ions on the glycosylation of human serum albumin (HSA) and the resulting formation of advanced glycosylation end products (AGEs). HSA in phosphate-buffered saline was incubated with 100 mmol/l glucose. The effect of addition of copper(II) ions and/or aminoguanidine bicarbonate (CAS 2582-30-1) was investigated. The determination of AGE levels derived from glycosylated/glycoxidated HSA was performed using a specific spectrofluorometric assay (excitation 346 nm; emission 418 nm). The results showed that the addition of copper(II) ions to the incubation medium containing glucose increased the formation of AGEs. Further, in the presence of copper(II) ions, a significant blockade of aminoguanidine inhibitory effect on the formation of AGEs was observed.

Novel Regiospecific Method for Synthesis of 2‐(3,5‐Diaryl‐4,5‐dihydro‐1H‐pyrazol‐1‐yl)‐4,6‐diarylpyrimidines

The facile, regiospecific, one‐pot synthesis of 2‐(3,5‐diaryl‐4,5‐dihydro‐1H‐pyrazol‐1‐yl)‐4,6‐diarylpyrimidines derivatives has been described, involving a [3+2] and [3+3] cyclocondensation between the α,β‐unsaturated ketones and aminoguanidine bicarbonate.

Synthesis and anticonvulsant activity of some potent 5,6-bis aryl 1,2,4-triazines.

In the present research, a series of 5,6-bis aryl 1,2,4-triazines 5a~5f were synthesized by condensation of various benzils 4a~4f with aminoguanidine bicarbonate and were screened in vivo, for their anticonvulsant and neurotoxicity studies. Compounds 5a, 5b and 5d were found to be potent molecules of this series, when compared with the reference drugs phenytoin sodium, diazepam and lamotrigine. The structures of these compounds were established by IR, (1)H NMR, (13)C NMR and mass spectroscopic data.

The oxidation of hydroquinone catalysed by Cu(II) ions immobilized on acrylic resins. The influence of ionic liquid

Series of acrylic resins with aminoguanidyl groups were prepared by aminolysis of nitrile groups in acrylonitrile, vinyl acetate and divinylbenzene terpolymer using aminoguanidine bicarbonate and hydrazine and subsequent substitution with thiourea/ethyl iodide (TEI) mixture. Complexation of the carriers with copper(II) acetate leads to the heterogenized catalysts with immobilized copper. Their catalytic activity was measured in the model oxidation reaction of hydroquinone (H 2Q) to p-benzoquinone (Q) using hydrogen peroxide. The catalysts were tested in the same reaction in the presence of ionic liquid [bmim]BF 4 (1-butyl-3-methylimidazolium tetrafluoroborate). Under optimal conditions the main product, i.e. p-benzoquinone was obtained after 60 min with 66% yield. The catalytic activity of the catalysts depends on Cu(II) loading and concentration of ion-exchange groups after sorption. Selectivity increases slightly in the presence of ionic liquid.