Ethanone Oxime Research Articles

Photoinduced Perfluoroalkyloximation of Alkenes with Simple Perfluoroalkyl Halides

Comprehensive SummaryIn this paper, the difunctionalizative perfluoroalkyloximation of alkenes has been developed for the first time. This photochemical method allows for the synthesis of various perfluoroalkyl ethanone oximes with excellent regioselectivity and good functional group tolerance. Our method employs the most common perfluoroalkyl source, perfluoroalkyl iodides, as Rf reagents. Besides long‐chain perfluoroalkyl groups, this approach could be extended to incorporating additional groups, including trifluoromethyl, difluoromethyl, sulfonyl, and malonate, selectively into olefins, resulting in a range of β‐substituted ethanone oximes. Notably, the potential of this method in the Fukuyama indole synthesis, generating novel 2‐perfluoroalkylated 3‐(α‐oximidobenzyl)indoles via a radical cascade mechanism with 2‐vinylphenylacryloyl isocyanate as the radical acceptor, presents a compelling avenue for drug synthesis. The protocol is efficient, scalable, and useful for late‐stage modification of bioactive molecules.

Effect of ligand substituents on the reactivity pathways of copper(II) complexes towards electrocatalytic water oxidation.

The electrocatalytic water oxidation activity of three copper(II) complexes [Cu(L1H)(L1)](ClO4) (1), [Cu(L2H)(L2)(H2O)](ClO4) (2) and [Cu(L3H)(L2)](ClO4) (3) with aryl oxime ligands L1H, L2H and L3H [L1H = 1-(pyridin-2-yl)methanone oxime, L2H = 1-(pyridin-2-yl)ethanone oxime and L3H = 1-(pyridin-2-yl)propanone oxime] was investigated. All the three ligands have in common a pyridyl group attached to the carbon centre of the oxime moiety and differ in the second substituent attached to the carbon centre. Electrochemical investigation of the catalytic activity of complexes 1, 2 and 3 shows that the nature of the substituent attached to the carbon centre has an influence on the catalytic pathway and overall catalytic activity of these complexes.

Bioactive Compounds in Barangan Banana Peel (Musa acuminata Colla.) as an Alternative for Antibacterial Drug Development

Barangan banana (Musa acuminata Colla.) is one of the banana varieties which is often found in Indonesia and is widely consumed so that banana peels become organic waste and need to be processed further. The novelty of this research is to prove the antibacterial activity of the ethanol extract contained in banana peels on the Pseudomonas aeruginosa bacteria which is supported by the GCMS instrument to show the active compounds contained which can be used in the development of anti-bacterial drugs. Pseudomonas aeruginosa is an opportunistic pathogen that is widespread and inhabits the homeland and environments in contact with humans and animals. These bacteria can attack infections of the skin, blood, lungs and digestive tract. The ethanol extract was tested against Pseudomonas aeruginosa using the agar well diffusion method. the compounds contained in the samples were analyzed using Phytochemical Test obtained alkaloids, flavonoid, terpenoids, steroids, saponins and tannins were obtained. There are six active compounds: Palmitinic acid (C16H32O2), Cyclopentanol acetate (C7H12O2), 1-(2-Thienyl) Ethanone oxime (C6H7NOS), 2-Furancarboxaldehyde (C5H4O2), 4H-Pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl- (C6H8O4), and 2(3H)-Furanone, 5-methyl- (C5H6O2) with percent area respectively : 3,49, 12,60, 26,46, 20,85, 3,82, and 2,98 %. Antibacterial activity with inhibition zone diameters at concentrations of 100, 50, 25, and 12.5 mg/ml were 12.80, 10.70, 5.00 and 2.00 mm, respectively. This work will advance the development of antimicrobial drugs.

Preparation of Hydrophobic Cryogel Containing Hydroxyoxime Extractant and Its Extraction Properties of Cu(Ⅱ).

Hydrophobic cryogels with monolithic supermacropores based on poly-trimethylolpropane trimethacrylate (pTrim) containing 1-(2-Hydroxyl-5-nonyphenyl)ethanone oxime (LIX84-I) were successfully prepared by a cryo-polymerization technique using organic solvents with freezing points between room temperature and around 0 °C as solvents. The prepared cryogels were characterized in terms of macroscopic shape and porous structure. The cryogels had a monolithic supermacroporous structure and high contents of LIX84-I depending on the added amount of the extractant to the monomer solution. The amount of LIX84-I impregnated in the cryogel had a linear relationship with the added amount of LIX84-I in the monomer solution for cryo-polymerization. Cu(II) in the aqueous solution was immediately adsorbed into the cryogel containing LIX84-I.

Structural, spectroscopic, theoretical calculation and Hirshfeld surface analyses of 3-D supramolecular dinuclear zinc(II) and copper(II) complexes

Two three-dimensional dinuclear zinc(II) and copper(II) complexes, [Zn2(L2)2(CH3COO)2] (1) and [Cu2(L2)2(NO3)2] (2) (HL2 = 1-(2-{[(E)-2-hydroxy-benzyli-dene]amino}phenyl)ethanone oxime), were synthesized by Zn(II) acetate tetrahydrate or Cu(II) nitrate trihydrate with based ligand HL1 (2-(2-phenoxy)-4-methyl-1,2-quinazoline-N3-oxide, H is the deprotonate hydrogen) originally. HL1 and both complexes were characterized by elemental analyses and spectroscopic methods, as well as were confirmed by single-crystal X-ray crystallography. It was revealed that two complexes had 2:2 ligand-to-metal ratios and 1 was hexa-coordinated whereas 2 was penta-coordinated. In the crystal structures, HL1 showed a chain-like, while complexes showed 2-D network stacking constructions, and both complexes further formed a 3-D supramolecular structure. The frontier molecular orbital energy of all compounds was calculated, and TD-DFT calculations were performed to analyze the electronic transitions of HL1 and both complexes. Additionally, the structural optimization and electronic transitions of the molecules were obtained via DFT calculations, molecular electrostatic potential (ESP), Hirshfeld surface analysis (HSA), and two-dimensional fingerprint (2D-FP), supporting X-ray diffraction results with the existence of the H···H and C/O···H bonds as the main interactions in the crystal lattice. Especially, cyclic voltammetry (CV) and electron paramagnetic resonance (EPR) spectroscopy properties of 2 were further analyzed. In terms of biological applications, all compounds were investigated for antibacterial activity, and the results displayed two complexes had the best antibacterial performance than others.

Decatungstate Catalyzed Photochemical Acetylation of C(sp3)-H Bonds.

A direct acetylation of inert C(sp3)-H bonds was developed that was catalyzed by decatungstate under visible light irradiation and was followed by radical addition-disassociation with phenylsulfonyl ethanone oxime. The reaction displays site-selectivity in multiple C(sp3)-H bonds without prefunctionalization and directing groups. Various functional groups are well-tolerated and natural molecules are structurally feasible. CF3-modified phenylsulfonyl ethanone oxime was discovered to be necessary for enhancing the electrophilicity of imine and lowering the C-S bond cleavage energy.

Spectroscopic studies, TD/DFT calculations, electrochemical, antibacterial, and Hirshfeld surface analysis of Ni(II) and Co(III) complexes based on 3-ethoxy salicylaldehyde

The ligand 2-(3-ethoxy-2-hydroxyphenyl)-4-methyl-1,2-dihydroquinazolin 3-oxide (HL1, H is the deprotonatable hydrogen) has been synthesized, and two metal complexes, namely [Ni(L2)2]·2CH3OH (1) and [Co(L2)2]·NO3·H2O (2) (where HL2 =1-(2-{[(E)-(3-ethoxy-2-hydroxybenzylidene]amino} phenyl)ethanone oxime) were obtained via complexation reaction between HL1 and nickel(II) acetate tetrahydrate or cobalt(II) nitrate hexahydrate. HL1 and both complexes were characterized by elemental analysis, as well as compared by spectroscopic methods such as FT-IR, UV–Vis and fluorescence spectroscopy. X-ray crystallography revealed that both complexes have distorted octahedral geometries but with a different configuration of the two tridentate (L2)– ligands around the metal centers. Complex 1 contained two lattice methanol molecules whereas 2 were counterbalanced by a nitrate anion beside an uncoordinated water molecule. The crystal structures show a 2-D and 3-D supramolecular architecture due to intermolecular interaction. Electrochemical properties of both complexes were tested by cyclic voltammetry and Electron paramagnetic resonance (EPR) spectroscopy of 2 was also investigated. Fascinatingly, antibacterial efficiencies of all compounds were compared. Furthermore, molecular electrostatic potential (ESP) was computed for both complexes to predict the reaction sites of electrophilic and nucleophilic attacks. Density Functional Theory (DFT) calculations were done to ascertain the optimum geometric configurations. The non-covalent interaction was determined using the Hirshfeld program.

Synthesis of New 1-Aryl-2-(3,5-dimethylpyrazol-1-yl)ethanone Oxime Ether Derivatives and Investigation of Their Cytotoxic Effects

In this study, 12 new 1-aryl-2-(3,5-dimethylpyrazol-1-yl)ethanone oxime ether derivatives were designed and synthesized to investigate their cytotoxic effects. The in vitro cytotoxic activities of the compounds were evaluated against cervix, colon, breast, glioma, neuroblastoma, and lung cancer cell lines, as well as a healthy cell line using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazo-lium bromide (MTT) assays with 5-fluorouracil (5-FU) as the reference compound. Compound 5f (IC50 = 5.13 µM) was found to be more effective than 5-FU (IC50 = 8.34 µM) in the C6 cancer cell line, and it had no cytotoxic effect on the L929 healthy cell line. Flow cytometry was used to investigate the mechanism of action of compound 5f on the cell cycle of the C6 cell line. The analysis showed that cell death was significantly due to apoptosis. These results indicate that compound 5f induces cell cycle arrest, and may be effective in treating glioma.

Two mono‐ and dinuclear Cu (II) complexes derived from 3‐ethoxy salicylaldehyde: X‐ray structures, spectroscopic, electrochemical, antibacterial activities, Hirshfeld surfaces analyses, and time‐dependent density functional theory studies

AbstractThe quinazoline‐type ligand 2‐(3‐ethoxy‐2‐hydroxyphenyl)‐4‐methyl‐1,2‐dihydroquinazolin 3‐oxide (HL1, H is the deprotonatable hydrogen) was synthesized. Two mono‐ and dinuclear Cu (II) complexes, [Cu(L2)2]·2CH3OH (1), and [Cu4(L2)4(NO3)2] (2) (HL2 = 1‐(2‐{[(E)‐(3‐ethoxy‐2‐hydroxybenzylidene]amino}phenyl)ethanone oxime), were obtained via complexation of HL1 with Cu (II) acetate monohydrate or Cu (II) nitrate trihydrate in methanol. HL1 and both complexes were characterized by elemental analyses and spectroscopic methods. The structures of complexes were confirmed by single‐crystal X‐ray crystallography and the ratio of ligand to metal in 1 was 2:1 whereas 2 was 1:1. In the crystal structures, hexa‐coordinated Cu (II) complex 1 was assembled into an infinite 1‐D, 2‐D network and 3‐D supramolecular framework. Complex 2 included four deprotonated (L2)− units, four coordinated Cu (II) and two coordinated nitrate anions, forming an infinite 2‐D layer and interesting butterfly‐shaped 3‐D supramolecular skeleton. Specifically, the Cu1 and Cu4 centers were four‐coordinated, while the Cu2 and Cu3 centers were penta‐coordinated in 2. Furthermore, electrochemical properties and antibacterial activities of both complexes were also investigated. In addition, the electron paramagnetic resonance (EPR) spectra of 1 and 2 were also studied. The optimal geometries, HOMO‐LUMO energies and molecular electrostatic potential diagrams of two complexes were calculated using density functional theory (DFT)/B3LYP, and specific electronic transitions in the UV–vis spectra of 1 and 2 were recorded by time‐dependent DFT (TD‐DFT) calculations. Additionally, the noncovalent interactions between both complexes were also confirmed by Hirshfeld surfaces.

Synthesis and cytotoxicity studies on new pyrazolecontaining oxime ester derivatives

Purpose: To synthesize a series of new 1-(2-naphthyl)-2-(1H-pyrazol-1-yl)ethanone oxime ester derivatives (5-12) with potential anticancer properties, and to determine their cytotoxic effects in mouse fibroblast and human neuroblastoma cell lines.
 Methods: The title compounds were obtained through sodium salt reaction of 1-(naphthalene-2-yl)-2- (1H-pyrazol-1-yl)etanone oxime (4) with various acyl chlorides. The cytotoxic effects were evaluated by MTS colorimetric assay, while physicochemical descriptors were calculated using QikProp software.
 Results: Most of the compounds showed approximately 50 – 60 % inhibition against SH-SY5Y neuroblastoma cells at 100 μM. Of these, compound 7a was the most active combination with an IC50 value of 85.94 µM. The toxic effect of the compounds on mouse fibroblast cell line was insignificant (p < 0.05) even when the dose was increased. The calculated physicochemical properties of the compounds were within drug-like chemical space.
 Conclusion: The synthesized oxime ester derivatives with pyrazole ring exhibit selective toxicity to neuroblastoma cells without affecting healthy mouse fibroblast cells. The compounds proved to be druglike while their pharmacokinetic features were also encouraging, and were in line with in silico predictions.

Two dinuclear copper (II) and nickel (II) complexes based on 4‐(diethylamino)salicylaldehyde: X‐ray structures, spectroscopic, electrochemical, antibacterial, Hirshfeld surfaces analyses, and time‐dependent density functional theory calculations

The quinazoline‐type ligand 2‐(4‐diethylamino‐2‐hydroxyphenyl)‐4‐methyl‐1,2‐dihydroquinazoline 3‐oxide (HL1; H is the deprotonatable hydrogen) was prepared. Two 2‐D supramolecular complexes [Cu2(L2)2(NO3)2] (1) and [Ni2(L2)2(CH3COO)2] (2) (L2 = 1‐(2‐{[(E)‐(4‐diethylamino‐2‐hydroxybenzylidene]amino} phenyl)ethanone oxime) were synthesized using HL1 and characterized by elemental analysis, spectroscopic methods, and single‐crystal X‐ray diffraction studies. It revealed that 1 had coordinated two nitrate ions whereas 2 had acetate ions. In the crystal structures, six‐coordinated Cu (II) complex 1 formed an infinite 2‐D and X‐shaped 3‐D supramolecular frameworks. Simultaneously, Ni (II) complex 2 assembled into wavy 2‐D networks. Furthermore, electrochemical properties and antimicrobial activities of all compounds were as well investigated. Afterwards, the electrophilic and nucleophilic attack sites identified by electrostatic potential (ESP) calculations confirmed that hydrogen bonds were observed in the optimized structure of the crystal, and the closest contact between the active atoms of both complexes was confirmed through Hirshfeld surface analysis and time‐dependent density functional theory (TD‐DFT) calculations.

Preparation, Synthesis New Azo Ligand (E)-1-(3- ((E)-(4,5-diphenyl-1H-imidazol-2- yl)diazenyl)phenyl)ethanone Oxime and Some of its Metal Complexes

Preparation, Synthesis New Azo Ligand (E)-1-(3- ((E)-(4,5-diphenyl-1H-imidazol-2- yl)diazenyl)phenyl)ethanone Oxime and Some of its Metal Complexes

Design, Synthesis and Antifungal Activity of Novel 1-(Adamantan-1-yl) ethanone Oxime Esters

Background: Oxime compounds, including oxime ethers and oxime esters, possess various biological activities. Many oxime ethers have been widely used in the fields of pesticides and medicines. However, oxime ethers are rarely used in the field of pesticides. Methods: We chose the excellent fungicide pyrifenox as the lead compound, integrated pyridinyl, adamantyl and benzoyl moieties into one molecule, while also designed and synthesized ten 1- (adamantan-1-yl)ethanone oxime esters containing pyridinyl moiety. Moreover, we also evaluated their preliminary antifungal activities against S. sclerotiorum and B. cinerea. Results: The target compounds were characterized by NMR, IR and HRMS. The preliminary bioactivity test showed that they exhibited some antifungal activity to S. sclerotiorum and B. cinerea, and EC50 values were in the range of 14.16-32.97 and 27.60-52.82 μg/mL, respectively. Conclusion: Some target compounds such as 3d, 3e, 3h and 3i, exhibited moderate activities against S. sclerotiorum, with EC50 values of 14.16-18.18 μg/mL.

Synthesis, crystal structure, TD/DFT calculations and Hirshfeld surface analysis of 1-(4-((Benzo)dioxol-5-ylmethyleneamino)phenyl)ethanone oxime

1-(4-((Benzo)dioxol-5-ylmethyleneamino)phenyl)ethanone oxime was synthesized using piperonal and characterized by 1H and 13C NMR spectrum, elemental analysis and UV–Vis spectroscopy, as well as by single-crystal X-ray crystallography. In the crystal structure, with the help of hydrogen bonds, C–H···π and π···π stacking interactions, a self-assembling two-dimensional (2-D) and three-dimensional (3-D) supramolecular frameworks were formed. The geometry of the compound had been optimized by the DFT method and the results were compared with the X-ray diffraction data. The calculated HOMO and LUMO energies showed the character of the title compound. The electronic transitions and spectral features were performed by TD-DFT calculations. The Electrostatic Potentials (ESP) analysis was utilized to visualize the charge distribution on the molecule, and the mapping demonstrated the reactive sites, which confirmed the observation of the optimized structure formed in the crystals by hydrogen bonds. In addition, the noncovalent supramolecular interactions among the compound were quantified by feat of Hirshfeld surface analysis.

Reinvestigation of the reaction of 3-substituted 1,2,4-triazines with nitronate anions: unexpected behavior of 3-(2-ethoxyphenyl)-1,2,4-triazine in the reaction with anions of nitroalkanes

3-Substituted 1,2,4-triazines easily react with nitronate anions to replace hydrogen atom in the position C-5 according to nucleophilic substitution mechanism and form appropriate oximes of 5-formyl- or 5-acyl-1,2,4-triazines. Present study has shown that the course of the reaction strongly depends on the structure of the substituent in the position C-3 of 1,2,4-triazine ring. Thus, 2-ethoxyphenyl substituent in 1,2,4-triazine allowed to form, besides appropriate oximes, also new nitronic acid derivatives stabilized by intramolecular hydrogen bonds. The synthesis pathway and molecular structures of oximes were confirmed by X-ray analysis performed for model compound 1-[3-(2-ethoxyphenyl)-1,2,4-triazin-5-yl]ethanone oxime. The presence of the new nitronic acid derivatives in the reaction mixture and the theoretical calculations at DFT/B3LYP/6-311++G(d,p) level strongly suggest that intermediate stabilized by bifurcated intramolecular hydrogen bond is a common intermediate for the construction of appropriate oximes.

Cube‐like 12‐MC‐4 and Offset Stacked 10‐MC‐3 Metallacrowns: Synthesis, Structure, and Magnetic Properties

Two complexes [MnIII4(naphthsao)4(naphthsaoH)4] (1) and [FeIII6O2(naphthsao)4(O2CPh)6] (2) [naphthsao = 1‐(1‐hydroxy‐naphthalen‐2‐yl)ethanone oxime] were obtained through the reactions of naphthsao ligand and MnCl2·4H2O or FeCl3·6H2O in the presence of triethylamine (Et3N). Their structures were determined by X‐ray single crystal diffraction, elemental analysis, and IR spectra. Complex 1 displays 12‐MC‐4 metallacrown structural type with cube‐like configuration and 2 shows an offset stacked 10‐MC‐3 structural type with the ring connectivity containing Fe–O–C–O–Fe–O–N–Fe–O–N. Magnetic susceptibility measurement reveals the ferromagnetic interactions and field‐induced slow relaxation of the magnetization for 1, whereas out‐of‐phase signal is not observed for 2.

New complexes of chelating Schiff base: Synthesis, spectral investigation, antimicrobial, and thermal behavior studies

The new bidentate Schiff base ligand (E)-1-(4-((E)-(4-(diethylamino)-2-hydroxybenzylidene)amino)phenyl)ethanone oxime [HL], has been synthesized via condensation equal amounts of 1-(4-aminophenyl)ethanone oxime and 4-Diethylaminosalicylaldehyde. The title ligand characterized by using (IR, UV-Vis) spectroscopies, (1H, 13C) NMR spectra, Mass spectrum and X-Ray crystallography. Chelated complexes of prepared ligand with Co(II), Ni(II) and Cu(II) ions, have been also prepared with a ratio of (1:2), (M:L) and characterized by (IR, UV-Vis) spectroscopies, magnetic susceptibility, molar conductivity and flame atomic absorption measurements. Results of spectral studies proved the chelation behavior of this ligand, which coordinated to metal ions as a monobasic N,O bidentate ligand, via imine and phenolic oxygen atom, after losing its proton. Tetrahedral geometry has been proposed for Co(II) complex and square planar geometry has been proposed for Ni(II) and Cu(II) complexes, respectively. The analysis studies of (TG/DTG/DTA) data reflected potential and good thermal stability of [HL] and its metal complexes. We also obtained the biological activity of the prepared compounds against two Gram-positive bacteria (Staphylococcus aureus & Staphylococcus epidermidis), four Gram-negative bacteria (Salmonella, E-coli., Pseudomonas aeruginosa & Klebsiella spp.) and one fungal (candida albicans).

Ligand assisted electrocatalytic water oxidation by a copper(ii) complex in neutral phosphate buffer.

The electrocatalytic water oxidation activity of a copper(ii) complex, 1, [Cu(L1H)(L1)(OH2)](ClO4), with a redox active aryl oxime ligand, L1H [L1H = 1-(pyridin-2-yl) ethanone oxime] has been investigated. Complex 1 shows a remarkably high turnover frequency of ∼100 s-1 in neutral phosphate buffer at about 675 mV overpotential with ∼94% faradaic efficiency. Electrochemical analysis suggests the involvement of a ligand moiety in a proton-coupled-electron-transfer (PCET) step during the catalytic cycle of complex 1, which in turn provides a route for accumulation of high oxidizing equivalents at the reaction center.

Synthesis of α-trifluoromethyl ethanone oximes via the three-component reaction of aryl-substituted ethylenes, tert-butyl nitrite, and the Langlois reagent

A three-component reaction of aryl-substituted ethylenes, tert-butyl nitrite, and the Langlois reagent to synthesize a-trifluoromethyl ethanone oximes was developed.

Synthesis, anticonvulsant screening, and molecular modeling studies of new arylalkylimidazole oxime ether derivatives.

In this study, 15 new oxime ether derivatives were synthesized and their anticonvulsant activities were screened in vivo. The compounds were synthesized by the reaction of various alkyl halides with 1-(2-naphthyl)-2-(1H-imidazol-1-yl)ethanone oxime. Their anticonvulsant activities were determined using acute (maximal electroshock, subcutaneous metrazol [SCM], and 6 Hz seizure test) and chronic (corneal-kindled mouse) seizure models, their neurotoxic effects were evaluated by models of behavioral toxicity according to the Epilepsy Therapy Screening Program protocol of the NIH. All our compounds were protective in at least one of the tests. Quantification studies were applied to some of the active compounds and the intraperitoneal ED50 values in mice were found between 25.48 and 99.56 mg/kg. Some pharmacokinetic properties of the compounds were predicted in silico and molecular docking studies were performed to provide insights into their possible anticonvulsant mechanism regarding their SCM activity.