An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Beilstein Journal of Organic Chemistry, Jul 30, 2013
A method for the synthesis of N-aryl-C-nitroazoles is presented. A coupling reaction between vari... more A method for the synthesis of N-aryl-C-nitroazoles is presented. A coupling reaction between variously substituted arylboronic acids and 3(5)-nitro-1H-pyrazole catalyzed by copper salt has been carried out in methanol in the presence of sodium hydroxide to afford the desired N-aryl-C-nitroazoles in good yields. This synthetic route has also been successfully applied to obtain N-phenyl derivatives of 4-nitropyrazole, 2-nitroimidazole, 4(5)-nitroimidazole and 3-nitro-1,2,4-triazole.
1H, 13C NMR (FID and processed spectra) and HR-MS spectroscopic data of amino-phenol chelating li... more 1H, 13C NMR (FID and processed spectra) and HR-MS spectroscopic data of amino-phenol chelating ligands, their derivatives with B-galactose, N,O-ligands and HR-MS spectra of Fe iron(III) complexes as bioresponsive, smart, enzyme sensitive systems
A facile stepwise synthesis of 2,5-disubstituted 1,3,4-oxadiazoles proceeding via oxidative cycli... more A facile stepwise synthesis of 2,5-disubstituted 1,3,4-oxadiazoles proceeding via oxidative cyclization of N-acylhydrazones is reported. The reaction is efficiently promoted by 2,3-dichloro-5,6-dicyano-1,4benzoquinone (DDQ) to afford the desired products mostly in high yields and in relatively short times. The final 1,3,4-oxadiazole derivatives are also synthesized directly from acid hydrazides and aldehydes in a one-pot procedure. The substrate scope and limitations of the reported transformation are discussed in detail.
The highly active, reusable and regioselective crown ethers bases catalytic systems, especially 1... more The highly active, reusable and regioselective crown ethers bases catalytic systems, especially 15-Crown-5/NaOH, 18-Crown-6/KOH, dibenzo-18-Crown/6-t-BuOK, and 18-Crown-6/t-BuOK, for double bond migration in various allyl and diallyl compounds have been presented. Allyl and/or diallyl: arenes and heteroarenes, ethers, acetal, sulfides, selenide, sulfoxides, imines, phosphine, and phosphine oxide were smoothly converted into their corresponding 1-propenyl derivatives under very mild conditions. Some of the C,O- and O,S-diallyl compounds were fully regioselectively isomerized to allyl-(1-propenyl) derivatives. An unprecedented and significant effect of increasing the reaction rate and shortening the quantitative reaction conversion time without decreasing the selectivity under ultrasound-assisted conditions was observed. Various solvents, including low-boiling point ones containing only C, H and/or O atoms, such as DMFL, DME, THF, Et2O, toluene, and 1,4-dioxane, can be used instead of the most frequently used DMSO. Remarkably highly effective recycling of 18-Crown-6/t-BuOK and dibenzo-18-Crown-6-t-BuOK catalytic systems for isomerization of low-boiling or high-boiling point allyl compounds respectively and crown ethers from all examined catalytic systems was developed. The opportunity to effectively combine the double bond migration with in situ generation of nitrile oxide and finally 1,3-DC-cycloaddition into one pot variant synthesis of isoxazolines from Qallyl has also been announced.
International Journal of Molecular Sciences, Mar 30, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
1H, 13C NMR (FID and processed spectra) and HR-MS spectroscopic data of amino-phenol chelating li... more 1H, 13C NMR (FID and processed spectra) and HR-MS spectroscopic data of amino-phenol chelating ligands, their derivatives with B-galactose, N,O-ligands and HR-MS spectra of Fe iron(III) complexes as bioresponsive, smart, enzyme sensitive systems
ABSTRACT The synthesis of several 3-arylquinazolin-4(3H)-imines by the simple heating of 2-amino-... more ABSTRACT The synthesis of several 3-arylquinazolin-4(3H)-imines by the simple heating of 2-amino-N′-arylbenzamidines in triethyl orthoformate solution at 100 °C is described.
The systems containing EHPG, EHPG-OCH 3 and EHPG-NH-Ac and Tb(III) ions were used to study chemil... more The systems containing EHPG, EHPG-OCH 3 and EHPG-NH-Ac and Tb(III) ions were used to study chemiluminescence (CL) and electrochemiluminescence (ECL) processes. In the CL studies the Fenton system (Fe(II)/(III)-H 2 O 2) was used as a source of reactive oxygen species (ROS). Kinetic CL curves and CL spectral distributions were recorded. On the basis of the results obtained, it was demonstrated that Tb(III) acted as a sensitizer. Similarly obtained CL decays in the systems of Fe(II)/(III)-EHPG (or its derivatives)-H 2 O 2 and Fe(II)/(III)-EHPG (or its derivatives)-Tb(III)-H 2 O 2 , independently on the Tb(III) concentration, showed that the lanthanide ions did not influence the kinetics of the oxidation of EHPG (or its derivatives) in the Fenton systems. The CL intensity increased with the increasing concentration of Tb(III) ions, which were the main emitters in the reaction systems. Spectrophotometric and luminescent studies of the systems before and after the additions of hydrogen peroxide proved that the excitation of the lanthanide ion was a result of energy transfer from the excited products of the oxidation of EHPG or its derivatives to the uncomplexed Tb(III) ions. ECL was generated on the surface of a nonstructural modified aluminum electrode with the use of K 2 S 2 O 8 , H 2 O 2 or KN 3 as coreactants in aqueous solution. In these studies we employed Al electrodes covered with a 2-4 nm layer of Al 2 O 3 doted with Tb(III) or Dy(III) ions. The electrodes were polarized using cathodic and anodic pulses of various amplitude and frequency. The relative ECL efficiencies were determined as a function of electric pulse parameters, electrolyte compositions and the thickness of barrier or porous layer of the Al 2 O 3 electrode.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
Beilstein Journal of Organic Chemistry, Jul 30, 2013
A method for the synthesis of N-aryl-C-nitroazoles is presented. A coupling reaction between vari... more A method for the synthesis of N-aryl-C-nitroazoles is presented. A coupling reaction between variously substituted arylboronic acids and 3(5)-nitro-1H-pyrazole catalyzed by copper salt has been carried out in methanol in the presence of sodium hydroxide to afford the desired N-aryl-C-nitroazoles in good yields. This synthetic route has also been successfully applied to obtain N-phenyl derivatives of 4-nitropyrazole, 2-nitroimidazole, 4(5)-nitroimidazole and 3-nitro-1,2,4-triazole.
1H, 13C NMR (FID and processed spectra) and HR-MS spectroscopic data of amino-phenol chelating li... more 1H, 13C NMR (FID and processed spectra) and HR-MS spectroscopic data of amino-phenol chelating ligands, their derivatives with B-galactose, N,O-ligands and HR-MS spectra of Fe iron(III) complexes as bioresponsive, smart, enzyme sensitive systems
A facile stepwise synthesis of 2,5-disubstituted 1,3,4-oxadiazoles proceeding via oxidative cycli... more A facile stepwise synthesis of 2,5-disubstituted 1,3,4-oxadiazoles proceeding via oxidative cyclization of N-acylhydrazones is reported. The reaction is efficiently promoted by 2,3-dichloro-5,6-dicyano-1,4benzoquinone (DDQ) to afford the desired products mostly in high yields and in relatively short times. The final 1,3,4-oxadiazole derivatives are also synthesized directly from acid hydrazides and aldehydes in a one-pot procedure. The substrate scope and limitations of the reported transformation are discussed in detail.
The highly active, reusable and regioselective crown ethers bases catalytic systems, especially 1... more The highly active, reusable and regioselective crown ethers bases catalytic systems, especially 15-Crown-5/NaOH, 18-Crown-6/KOH, dibenzo-18-Crown/6-t-BuOK, and 18-Crown-6/t-BuOK, for double bond migration in various allyl and diallyl compounds have been presented. Allyl and/or diallyl: arenes and heteroarenes, ethers, acetal, sulfides, selenide, sulfoxides, imines, phosphine, and phosphine oxide were smoothly converted into their corresponding 1-propenyl derivatives under very mild conditions. Some of the C,O- and O,S-diallyl compounds were fully regioselectively isomerized to allyl-(1-propenyl) derivatives. An unprecedented and significant effect of increasing the reaction rate and shortening the quantitative reaction conversion time without decreasing the selectivity under ultrasound-assisted conditions was observed. Various solvents, including low-boiling point ones containing only C, H and/or O atoms, such as DMFL, DME, THF, Et2O, toluene, and 1,4-dioxane, can be used instead of the most frequently used DMSO. Remarkably highly effective recycling of 18-Crown-6/t-BuOK and dibenzo-18-Crown-6-t-BuOK catalytic systems for isomerization of low-boiling or high-boiling point allyl compounds respectively and crown ethers from all examined catalytic systems was developed. The opportunity to effectively combine the double bond migration with in situ generation of nitrile oxide and finally 1,3-DC-cycloaddition into one pot variant synthesis of isoxazolines from Qallyl has also been announced.
International Journal of Molecular Sciences, Mar 30, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
1H, 13C NMR (FID and processed spectra) and HR-MS spectroscopic data of amino-phenol chelating li... more 1H, 13C NMR (FID and processed spectra) and HR-MS spectroscopic data of amino-phenol chelating ligands, their derivatives with B-galactose, N,O-ligands and HR-MS spectra of Fe iron(III) complexes as bioresponsive, smart, enzyme sensitive systems
ABSTRACT The synthesis of several 3-arylquinazolin-4(3H)-imines by the simple heating of 2-amino-... more ABSTRACT The synthesis of several 3-arylquinazolin-4(3H)-imines by the simple heating of 2-amino-N′-arylbenzamidines in triethyl orthoformate solution at 100 °C is described.
The systems containing EHPG, EHPG-OCH 3 and EHPG-NH-Ac and Tb(III) ions were used to study chemil... more The systems containing EHPG, EHPG-OCH 3 and EHPG-NH-Ac and Tb(III) ions were used to study chemiluminescence (CL) and electrochemiluminescence (ECL) processes. In the CL studies the Fenton system (Fe(II)/(III)-H 2 O 2) was used as a source of reactive oxygen species (ROS). Kinetic CL curves and CL spectral distributions were recorded. On the basis of the results obtained, it was demonstrated that Tb(III) acted as a sensitizer. Similarly obtained CL decays in the systems of Fe(II)/(III)-EHPG (or its derivatives)-H 2 O 2 and Fe(II)/(III)-EHPG (or its derivatives)-Tb(III)-H 2 O 2 , independently on the Tb(III) concentration, showed that the lanthanide ions did not influence the kinetics of the oxidation of EHPG (or its derivatives) in the Fenton systems. The CL intensity increased with the increasing concentration of Tb(III) ions, which were the main emitters in the reaction systems. Spectrophotometric and luminescent studies of the systems before and after the additions of hydrogen peroxide proved that the excitation of the lanthanide ion was a result of energy transfer from the excited products of the oxidation of EHPG or its derivatives to the uncomplexed Tb(III) ions. ECL was generated on the surface of a nonstructural modified aluminum electrode with the use of K 2 S 2 O 8 , H 2 O 2 or KN 3 as coreactants in aqueous solution. In these studies we employed Al electrodes covered with a 2-4 nm layer of Al 2 O 3 doted with Tb(III) or Dy(III) ions. The electrodes were polarized using cathodic and anodic pulses of various amplitude and frequency. The relative ECL efficiencies were determined as a function of electric pulse parameters, electrolyte compositions and the thickness of barrier or porous layer of the Al 2 O 3 electrode.
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