Chalcone Oximes Research Articles

A Review of the In Vitro Inhibition of α-Amylase and α-Glucosidase by Chalcone Derivatives.

Diabetes mellitus is a chronicmetabolic disease relating to steady hyperglycemia resulting from the impairment of the endocrine and non-endocrine systems. Many new drugs havingvaried targets were discovered to treat this disease, especially type 2 diabetes. Among those, α-glucosidase inhibitors showed their effects by preventing the digestion of carbohydrates through their inhibition against α-amylase and α-glucosidase. Recently, chalcones have attracted considerable attention as they have a simple structure, are easily synthesized as well as have a variety of derivatives. Some reports suggested that chalcone and its derivates could inhibit α-amylase and α-glucosidase. This narrative review provides a comprehensive evaluation of the inhibition of chalcone and its derivatives against α-amylase and α-glucosidase that were reviewed and reported in published scientific articles. Twenty-eight articles were reviewed after screening 207 articles found in four databases, including PubMed, Google Scholar, VHL (Virtual Health Library), and GHL (Global Health Library). This review presented the inhibitory effects of varied chalcones,including chalcones with a basic structural framework,azachalcones, bis-chalcones, chalcone oximes, coumarin-chalcones, cyclohexane chalcones, dihydrochalcones, and flavanone-coupled chalcones. Many of these chalcones had significant inhibition against α-amylase as well as α-glucosidase that were comparable to or even stronger than standard inhibitors. This suggested that such compounds could be potential candidates for the discovery of new anti-diabetic remedies in the years to come.

Performance Evaluation of New Chalcone Oxime Functionalized Graphene Oxide as a Corrosion Inhibitor for Carbon Steel in a Hydrochloric Acid Solution

This study aims to synthesize new chalcone oxime functionalized graphene oxide (CO-GO) and investigate the enhancement in corrosion protection. The morphology and structure of the synthesized CO-GO have been characterized by elemental analysis: Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermal gravimetric analysis (TGA), and scanning electron microscopy (SEM). Moreover, the effectiveness of corrosion inhibition was investigated by utilizing electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP). The results of the above analyses demonstrate that CO-GO has an outstanding corrosion inhibitor performance of up to 94% and acts as a mixed-type inhibitor with a primarily anodic action. The effect of temperature on a carbon steel surface indicates that the tested composites are chemisorbed. A few techniques were able to provide surface characterization such as scanning electron microscopy and ultraviolet (UV)-visible spectroscopy to confirm inhibitor adsorption on the carbon steel surface.

Corrosion inhibition behavior of chalcone oxime derivatives on carbon steel in 0.5 M H2SO4

Corrosion inhibition behavior of chalcone oxime derivatives on carbon steel in 0.5 M H2SO4

Chalcone oxime derivatives as new inhibitors corrosion of carbon steel in 1 M HCl solution

In this research, 1,3-diphenylprop-2-en-1-one oxime (CO) and 4-nitrophenyl-1-phenylprop-2-en-1-one(CO-NO2) was synthesized and its adsorption properties and corrosion inhibition ability was evaluated for carbon steel (CS) in 1 M HCl at 293–323 K temperature using chemical and electrochemical techniques such as weight loss measurements (WL), potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). Results evince that the inhibition activity (IE%) enhances with the compounds concentration and may achieve a maximum of 95 and 91% for CO and CO-NO2, respectively at 293 K. In obedience with PDP findings, the tested compounds act as some mixed-type inhibitors. Survey of the temperature effect discloses that the inhibitory molecule is chemisorbed on carbon steel substrate. The adsorption of CO and CO-NO2 occurs in accordance to the Langmuir’s isotherm. Scanning Electron Microscopy (SEM) and UV–visible revealed the development of barrier film hindering the access of aggressive ions into steel surface. The theoretical findings suggested by electronic/atomic computer simulations supported the inhibitive chemicals interfacial adsorption through reactive centers.

Novel Class of Chalcone Oxime Ethers as Potent Monoamine Oxidase-B and Acetylcholinesterase Inhibitors.

Previously synthesized novel chalcone oxime ethers (COEs) were evaluated for inhibitory activities against monoamine oxidases (MAOs) and acetylcholinesterase (AChE). Twenty-two of the 24 COEs synthesized, except COE-17 and COE-24, had potent and/or significant selective inhibitory effects on MAO-B. COE-6 potently inhibited MAO-B with an IC50 value of 0.018 µM, which was 105, 2.3, and 1.1 times more potent than clorgyline, lazabemide, and pargyline (reference drugs), respectively. COE-7, and COE-22 were also active against MAO-B, both had an IC50 value of 0.028 µM, which was 67 and 1.5 times lower than those of clorgyline and lazabemide, respectively. Most of the COEs exhibited weak inhibitory effects on MAO-A and AChE. COE-13 most potently inhibited MAO-A (IC50 = 0.88 µM) and also significantly inhibited MAO-B (IC50 = 0.13 µM), and it could be considered as a potential nonselective MAO inhibitor. COE-19 and COE-22 inhibited AChE with IC50 values of 5.35 and 4.39 µM, respectively. The selectivity index (SI) of COE-22 for MAO-B was higher than that of COE-6 (SI = 778.6 vs. 222.2), but the IC50 value (0.028 µM) was slightly lower than that of COE-6 (0.018 µM). In reversibility experiments, inhibitions of MAO-B by COE-6 and COE-22 were recovered to the levels of reference reversible inhibitors and both competitively inhibited MAO-B, with Ki values of 0.0075 and 0.010 µM, respectively. Our results show that COE-6 and COE-22 are potent, selective MAO-B inhibitors, and COE-22 is a candidate of dual-targeting molecule for MAO-B and AChE.

An Easy Access to Oxime Ethers by Pd‐Catalyzed C—O Cross‐Coupling of Activated Aryl Bromides with Ketoximes and Chalcone Oximes

Summary of main observation and conclusionAn efficient Pd‐catalyzed method for C—O cross‐coupling of ketoximes and chalcone oximes with activated aryl bromides and bromo‐chalcones has been developed. All oxime ethers were obtained in good to excellent yields by [(π‐allyl)PdCl]2/tBuXPhos (L7) catalyst system. TrixiePhos (L11) was also found to be effective for the oxime coupling. This method offers an easy and smooth coupling of chalcone oximes with activated aryl bromides and bromo‐chalcones, which has not been previously explored.

K2S2O8‐Mediated Efficient Oxidative Deoximation of Flavonoid Oximes under Mild Reaction Conditions

AbstractDeveloped a novel K2S2O8‐mediated methodology for the oxidative deoximation of flavanone and chalcone oximes to synthesize the corresponding flavanones and chalconesin good to excellent yields (92‐70%). Our methodology is successfully applied for the deoximation of flavanone oximes, chalcone oximes, ketoximes and aldoximes. This methodology is equally useful for the hindered and functionalized aldoximes and ketoximes. Mild reaction condition, shorter reaction time, high yields, easy work‐up and purification of the products are the key advantages of the methodology.

Microwave-Assisted Synthesis and Characterization of Oxime Derivative of Substituted Chalcone and Its Nickel(II) Complex

In this study, microwave-assisted green synthesis of a complex of Ni (II)-2′,4′-dihydroxy 4-fluoro chalcone oxime has been carried out. The structure of the complex was characterized by elemental analysis, molar conductance, magnetic moment, IR, 1 H-NMR, 13 CNMR spectroscopic data and thermal studies. IR data showed that Ni(II) is coordinated to the ligand through the phenolic-O and azomethine-N of the latter. TGA studies confirmed the presence of coordinated water molecules. The 1 : 2 metal to ligands stoichiometry was indicated by mole ratio method, which was further confirmed by Job’s method of continuous variation modified by Turner and Anderson. Stability constant ( K s) of the complex determined by mole ratio method was 8.5245. Standard free energy change (Δ G 0 ) for metal–ligand complex formation was found to be –11.7026 K cal/mol at 27 ± 2°C. On the basis of analytical data, octahedral structure has been proposed for the complex. All compounds were tested for antibacterial activity and showed moderate to good activity against Escherichia coli and Staphylococcus aureus at different concentrations. In this study, we report synthesis of oxime derivative of chalcone and its Ni(II) complex in the hope of developing new compounds which might be used as analytical reagents or intermediates in the synthesis of various classes of bioactive compounds.

Synthesis, Theoretical Calculation and α-glucosidase inhibition of new chalcone oximes

Synthesis, Theoretical Calculation and α-glucosidase inhibition of new chalcone oximes

An Improved, Efficient and Microwave Assisted Synthetic Method for the Synthesis of Chalcone Oximes: An Experimental and Computational Study

An Improved, Efficient and Microwave Assisted Synthetic Method for the Synthesis of Chalcone Oximes: An Experimental and Computational Study

TBAI-catalyzed intramolecular annulation of chalcone oximes toward isoxazoles

A TBAI-catalyzed intramolecular annulation of chalcone oximes toward isoxazoles was developed, providing 3,5-diarylisoxazoles in good yields. Functional groups such as methoxy, ethyoxyl, chloro, bromo, fluoro and nitro were well tolerated in this reaction. Notably, the reaction ran under metal-free in water.

Evaluation of Novel Chalcone Oximes as Inhibitors of Tyrosinase and Melanin Formation in B16 Cells.

A series of hydroxy-substituted chalcone oxime derivatives were synthesized. These compounds were then evaluated for their inhibitory activities on tyrosinase and melanogenesis in murine B16F10 melanoma cells. The structures of the synthesized compounds were confirmed by (1) H NMR, (13) C NMR, FTIR, and HRMS. Two of the compounds exhibited much higher tyrosinase inhibitory activities (IC50 values of 4.77 and 7.89 μM, respectively) than the positive control, kojic acid (IC50 : 22.25 μM). Kinetic studies revealed them to act as competitive tyrosinase inhibitors with their Ki values of 5.25 and 8.33 μM, respectively. Both the compounds inhibited melanin production and tyrosinase activity in B16 cells. Docking results confirmed that the active inhibitors strongly interacted with the mushroom tyrosinase residues.

Integrated kinetic studies and computational analysis on naphthyl chalcones as mushroom tyrosinase inhibitors.

Melanin helps to protect skin from the damaging ultraviolet radiation of the sun. Tyrosinase, the key enzyme in melanogenesis is responsible for coloration of skin, hair and eyes. This enzyme is considered to have a critical role in governing the quality and economics of fruits and vegetables, as tyrosinase activity can lead to spoilage through browning. Development of tyrosinase inhibitors is a promising approach to combat hyperpigmentation conditions like ephelides, lentigo, freckles and post-inflammatory hyperpigmentation. In the present study, we have used a docking algorithm to simulate binding between tyrosinase and hydroxy-substituted naphthyl chalcone oxime compounds and studied the inhibition of tyrosinase. The results of virtual screening studies indicated that the estimated free energy of binding of all the docked ligands ranged between -19.29 and -9.12 kcal/mol. Two of the oximes synthesized were identified as competitive tyrosinase inhibitors and were found to be twice as potent as the control kojic acid with their IC50 values of 12.22 μM and 19.45 μM, respectively. This strategy of integrating experimental and virtual screening methods could give better insights to explore potent depigmentation agents.

Electrochemical synthesis of 3,5-disubstituted isoxazoles

The electrochemical oxidation of chalcone oximes has been explored using preparative scale electrolysis and cyclic voltammetry (CV). The results show that a constant current electrolysis of chalcone oximes in an undivided cell affords the corresponding isoxazoles in moderate to good yields, using graphite as the working electrode and NaClO4/CH3OH as the supporting electrolyte. The cyclic voltammograms for nearly all of the chalcone oximes investigated exhibit only one oxidation peak. On the basis of preparative electrolysis results and CV analysis, a reaction mechanism, involving a combination of electrochemically-generated base and an iminoxy radical intermediate, is proposed.

ChemInform Abstract: Synthesis of 3,5‐Diarylisoxazoles under Solvent‐Free Conditions Using Iodobenzene Diacetate.

AbstractA simple and solvent‐free reaction of chalcone oximes with iodobenzene diacetate to synthesize 3,5‐diarylisoxazoles (II) (17 examples) in good yields is shown.

Synthesis, biological evaluation, and molecular docking studies of novel chalcone oxime derivatives as potential tubulin polymerization inhibitors

Compounds of novel chalcone oxime derivatives containing different substituent groups were designed, synthesized and evaluated for the inhibitory activity against tubulin polymerization and cancer cell inhibitory activity.

Synthesis of 3,5-diarylisoxazoles under solvent-free conditions using iodobenzene diacetate

Abstract A simple and efficient method has been developed for conversion of chalcone oximes to 3,5-diaryl isoxazoles in excellent yields under solvent-free conditions. The synthesized compounds were characterized by infrared spectroscopy, 1 H NMR, 13 C NMR and HRMS.

Design, synthesis, and biological evaluation of chalcone oxime derivatives as potential immunosuppressive agents

A series of deoxybenzoin oximes were recently reported as potent immunosuppressive agents by our group. In order to continue the original research for potential immunosuppressive agents with high efficacy and low toxicity, we synthesized a series of new chalcone oximes and evaluated them for their cytotoxicities and immunosuppressive activities. Among the synthesized compounds, chalcone oximes 25 and 27 exhibited lower cytotoxicities and higher inhibitory activities on anti-CD3/anti-CD28 co-stimulated lymph node cells than other compounds. Specially, compound 27 displayed 200-fold lower cytotoxicity (CC50=2174.39μM) than cyclosporin A (CC50=10.10μM) and showed SI value (SI=176.69) close to cyclosporin A (SI=154.13). Besides, the preliminary mechanism of inhibition effect of compounds 25 and 27 was also detected by flow cytometry, and the compounds exerted immunosuppressive activities via inducing the apoptosis of activated lymph node cells in a dose dependent manner. Also, the deep mechanism of apoptosis was detected by Western blot analysis.

A Convenient Preparation of 3,5-Diarylisoxazoles

3,5-Diarylisoxazoles 2 a-i were prepared in moderate to high yields (51-94%) by oxidation of chalcone oximes with a new metal complex oxidant, tetrakis(pyridine)cobalt(II) dichromate (TPCD).

Synthesis and Physicochemical Studies on Ruthenium(III) and Rhodium(III) Complexes with Chalcone Oximes

Abstract The reactions of ruthenium(III) and rhodium(III) chloride with neutral chalcone oximes (COxH). 2-hydroxychalcone oximes (COx′H-). 2′-hydroxychalcone oxime (SCOx″H2) and 2, 2′-dihydroxychalcone oxime (DCOx″′H3) have been studied in absolute ethanol and complexes of types [M(COxH)3Cl3], [M(COx′H)3], [M(SCOx″H)3] and [M(DCOx″′H2)2Cl] have been isolated, and characterized on the basis of elemental analyses, electrical conductance, magnetic moment and spectral (electronic, infrared and 1H n. m. r.) data. The probable structures of the complexes are suggested.