Nadezhda Demina - Academia.edu (original) (raw)
Papers by Nadezhda Demina
Frontiers in Pharmacology
We investigated the inhibitory activities of novel 9-phosphoryl-9,10-dihydroacridines and 9-phosp... more We investigated the inhibitory activities of novel 9-phosphoryl-9,10-dihydroacridines and 9-phosphorylacridines against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and carboxylesterase (CES). We also studied the abilities of the new compounds to interfere with the self-aggregation of β-amyloid (Aβ42) in the thioflavin test as well as their antioxidant activities in the ABTS and FRAP assays. We used molecular docking, molecular dynamics simulations, and quantum-chemical calculations to explain experimental results. All new compounds weakly inhibited AChE and off-target CES. Dihydroacridines with aryl substituents in the phosphoryl moiety inhibited BChE; the most active were the dibenzyloxy derivative 1d and its diphenethyl bioisostere 1e (IC50 = 2.90 ± 0.23 µM and 3.22 ± 0.25 µM, respectively). Only one acridine, 2d, an analog of dihydroacridine, 1d, was an effective BChE inhibitor (IC50 = 6.90 ± 0.55 μM), consistent with docking results. Dihydroacridines inhibited Aβ4...
ChemistrySelect, 2021
A series of [1,2,4]triazolo[1,5‐a]pyrimidine‐cored push‐pull compounds, bearing ethynyl moieties,... more A series of [1,2,4]triazolo[1,5‐a]pyrimidine‐cored push‐pull compounds, bearing ethynyl moieties, was effectively prepared using transition‐metal‐free strategy involving the direct C−H functionalization of [1,2,4]triazolo[1,5‐a]pyrimidine scaffold with the Grignard‐Iocich reagents (ethynylmagnesium bromides). The basic optical and electrochemical properties of the synthesized derivatives were studied and gave grounds to consider the obtained compounds as promising UV dyes with high quantum yields.
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.
Organic & Biomolecular Chemistry, 2020
A number of 2,3-disubstituted benzo[b]thieno[2,3-d]thiophenes and benzo[4,5]selenopheno[3,2-b]thi... more A number of 2,3-disubstituted benzo[b]thieno[2,3-d]thiophenes and benzo[4,5]selenopheno[3,2-b]thiophenes have been obtained using a convenient approach based on the Fiesselmann thiophene synthesis.
Synlett, 2021
A series of 12H-[1]benzo[4′′,5′′]thieno[2′′,3′′:4′,5′]thieno[2′,3′:4,5]thieno[3,2-b]indoles were ... more A series of 12H-[1]benzo[4′′,5′′]thieno[2′′,3′′:4′,5′]thieno[2′,3′:4,5]thieno[3,2-b]indoles were efficiently prepared in three steps starting from available benzo[b]thieno[2,3-d]thiophen-3(2H)-ones. These fused ketones were treated with the Vilsmeier reagent and hydroxylamine hydrochloride to give the corresponding 3-chlorobenzo[b]thieno[2,3-d]thiophene-2-carbonitriles, which then reacted with methyl sulfanylacetate to form methyl 3-aminobenzo[4′,5′]thieno[2′,3′:4,5]thieno[3,2-b]thiophene-2-carboxylates, in accordance with the Fiesselmann thiophene synthesis protocol. Finally, the desired N,S-heterohexacenes were obtained by conversion of these fused 3-aminothiophene-2-carboxylates into the corresponding 3-aminothiophene intermediates, which acted as synthetic equivalents of thiophen-3(2H)-ones, followed by their acid-promoted reaction with arylhydrazines, in accordance with the Fischer indolization procedure.
![Research paper thumbnail of Synthesis of aryl-substituted thieno[3,2-b]thiophene derivatives and their use for N,S-heterotetracene construction](https://attachments.academia-assets.com/110668837/thumbnails/1.jpg)
](Beilstein Journal of Organic Chemistry, 2019
Fiesselmann thiophene synthesis was applied for the convenient construction of thieno[3,2-b]thiop... more Fiesselmann thiophene synthesis was applied for the convenient construction of thieno[3,2-b]thiophene derivatives. Thus, new 5- or 6-aryl-3-hydroxythieno[3,2-b]thiophene-2-carboxylates were obtained by condensation of 5- or 4-aryl-3-chlorothiophene-2-carboxylates, respectively, with methyl thioglycolate in the presence of potassium tert-butoxide. The saponification of the resulting esters, with decarboxylation of the intermediating acids, gave the corresponding thieno[3,2-b]thiophen-3(2H)-ones. The latter ketones were used to synthesize new N,S-heterotetracenes, namely 9H-thieno[2',3':4,5]thieno[3,2-b]indoles by their treatment with arylhydrazines in accordance with the Fischer indolization reaction.
![Research paper thumbnail of Modifications of 5,12-dihydroindolo[3,2-a]carbazole scaffold via its regioselective C2,9-formylation and C2,9-acetylation](https://attachments.academia-assets.com/110668853/thumbnails/1.jpg)
](Tetrahedron, 2019
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service... more This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
![Research paper thumbnail of Construction of new heteroacenes based on benzo[b]thieno[2,3-d]thiophene / quinoline or 1,8-naphthyridine systems using the Friedländer reaction](https://attachments.academia-assets.com/110668851/thumbnails/1.jpg)
](Tetrahedron Letters, 2019
Construction of new heteroacenes based on benzo[b]thieno[2,3-d]thiophene / quinoline or 1,8-napht... more Construction of new heteroacenes based on benzo[b]thieno[2,3-d]thiophene / quinoline or 1,8-naphthyridine systems using the Friedländer reaction
![Research paper thumbnail of Direct (het)arylation of [1,2,4]triazolo[1,5- a ]pyrimidines: Both eliminative and oxidative pathways](https://attachments.academia-assets.com/110668852/thumbnails/1.jpg)
](Tetrahedron, 2017
(Hetero)arylation of [1,2,4]triazolo[1,5-a]pyrimidine through the direct nucleophilic C-H functio... more (Hetero)arylation of [1,2,4]triazolo[1,5-a]pyrimidine through the direct nucleophilic C-H functionalization of the C-7 and C-5 positions has been implemented. The regioselective addition of a (het)aryl magnesium bromide to C-7 of 6-bromo-[1,2,4]triazolo[1,5-a]pyrimidine, followed by eliminative aromatization of the intermediate σ H-adducts, has afforded 7-(hetero)arylsubstituted [1,2,4]triazolo[1,5-a]-pyrimidines (the ܵ ே ு reaction, proceeding according to the "addition-elimination" scheme). A second treatment with a Grignard reagent has resulted in the C-5 σ H-adducts, which have been oxidized while being N-magnesium salts into [1,2,4]triazolo[1,5-a]pyrimidines, bearing various combinations of (hetero)aromatic substituents at C-5 and C-7 (the ܵ ே ு process, realizing via the "addition-oxidation" scheme). As a result of optical and electrochemical studies, the obtained compounds have proved to be promising luminescent dyes and push-pull systems.
Journal of fluorescence, Jan 31, 2015
Novel donor-π-acceptor dyes bearing the pyrimidine unit as an electron-withdrawing group have bee... more Novel donor-π-acceptor dyes bearing the pyrimidine unit as an electron-withdrawing group have been synthesized by using combination of two processes, based on the microwave-assisted Suzuki cross-coupling reaction and nucleophilic aromatic substitution of hydrogen. Spectral properties of the obtained dyes in six aprotic solvents of various polarities have been studied by ultraviolet-visible and fluorescence spectroscopy. In contrast to the absorption spectra, fluorescence emission spectra displayed a strong dependence from their solvent polarities. The nature of the observed long wavelength maxima has been elucidated by means of quantum chemical calculations. The electrochemical properties of these dyes have been investigated by using cyclic voltammetry, while their photovoltaic performance was evaluated by a device fabrication study. The experimental and calculation data show that all of the dyes can be regarded as potentially good photosensitizers for dye-sensitized solar cells.
Synthesis, 2021
The effect of chalcogenophosphoryl fragments on the anodic oxidation of 9-chalcogenophosphoryl-9,... more The effect of chalcogenophosphoryl fragments on the anodic oxidation of 9-chalcogenophosphoryl-9,10-dihydroacridines was studied in detail. The data of X-ray structural analyses, quantum chemical calculations, and cyclic voltammetry measurements obtained for these compounds provide an explanation of the observed features. The direct electrochemical phosphorylation of acridine was first carried out successfully.
Frontiers in Pharmacology
We investigated the inhibitory activities of novel 9-phosphoryl-9,10-dihydroacridines and 9-phosp... more We investigated the inhibitory activities of novel 9-phosphoryl-9,10-dihydroacridines and 9-phosphorylacridines against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and carboxylesterase (CES). We also studied the abilities of the new compounds to interfere with the self-aggregation of β-amyloid (Aβ42) in the thioflavin test as well as their antioxidant activities in the ABTS and FRAP assays. We used molecular docking, molecular dynamics simulations, and quantum-chemical calculations to explain experimental results. All new compounds weakly inhibited AChE and off-target CES. Dihydroacridines with aryl substituents in the phosphoryl moiety inhibited BChE; the most active were the dibenzyloxy derivative 1d and its diphenethyl bioisostere 1e (IC50 = 2.90 ± 0.23 µM and 3.22 ± 0.25 µM, respectively). Only one acridine, 2d, an analog of dihydroacridine, 1d, was an effective BChE inhibitor (IC50 = 6.90 ± 0.55 μM), consistent with docking results. Dihydroacridines inhibited Aβ4...
ChemistrySelect, 2021
A series of [1,2,4]triazolo[1,5‐a]pyrimidine‐cored push‐pull compounds, bearing ethynyl moieties,... more A series of [1,2,4]triazolo[1,5‐a]pyrimidine‐cored push‐pull compounds, bearing ethynyl moieties, was effectively prepared using transition‐metal‐free strategy involving the direct C−H functionalization of [1,2,4]triazolo[1,5‐a]pyrimidine scaffold with the Grignard‐Iocich reagents (ethynylmagnesium bromides). The basic optical and electrochemical properties of the synthesized derivatives were studied and gave grounds to consider the obtained compounds as promising UV dyes with high quantum yields.
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.
Organic & Biomolecular Chemistry, 2020
A number of 2,3-disubstituted benzo[b]thieno[2,3-d]thiophenes and benzo[4,5]selenopheno[3,2-b]thi... more A number of 2,3-disubstituted benzo[b]thieno[2,3-d]thiophenes and benzo[4,5]selenopheno[3,2-b]thiophenes have been obtained using a convenient approach based on the Fiesselmann thiophene synthesis.
Synlett, 2021
A series of 12H-[1]benzo[4′′,5′′]thieno[2′′,3′′:4′,5′]thieno[2′,3′:4,5]thieno[3,2-b]indoles were ... more A series of 12H-[1]benzo[4′′,5′′]thieno[2′′,3′′:4′,5′]thieno[2′,3′:4,5]thieno[3,2-b]indoles were efficiently prepared in three steps starting from available benzo[b]thieno[2,3-d]thiophen-3(2H)-ones. These fused ketones were treated with the Vilsmeier reagent and hydroxylamine hydrochloride to give the corresponding 3-chlorobenzo[b]thieno[2,3-d]thiophene-2-carbonitriles, which then reacted with methyl sulfanylacetate to form methyl 3-aminobenzo[4′,5′]thieno[2′,3′:4,5]thieno[3,2-b]thiophene-2-carboxylates, in accordance with the Fiesselmann thiophene synthesis protocol. Finally, the desired N,S-heterohexacenes were obtained by conversion of these fused 3-aminothiophene-2-carboxylates into the corresponding 3-aminothiophene intermediates, which acted as synthetic equivalents of thiophen-3(2H)-ones, followed by their acid-promoted reaction with arylhydrazines, in accordance with the Fischer indolization procedure.
Beilstein Journal of Organic Chemistry, 2019
Fiesselmann thiophene synthesis was applied for the convenient construction of thieno[3,2-b]thiop... more Fiesselmann thiophene synthesis was applied for the convenient construction of thieno[3,2-b]thiophene derivatives. Thus, new 5- or 6-aryl-3-hydroxythieno[3,2-b]thiophene-2-carboxylates were obtained by condensation of 5- or 4-aryl-3-chlorothiophene-2-carboxylates, respectively, with methyl thioglycolate in the presence of potassium tert-butoxide. The saponification of the resulting esters, with decarboxylation of the intermediating acids, gave the corresponding thieno[3,2-b]thiophen-3(2H)-ones. The latter ketones were used to synthesize new N,S-heterotetracenes, namely 9H-thieno[2',3':4,5]thieno[3,2-b]indoles by their treatment with arylhydrazines in accordance with the Fischer indolization reaction.
Tetrahedron, 2019
This is a PDF file of an unedited manuscript that has been accepted for publication. As a service... more This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Tetrahedron Letters, 2019
Construction of new heteroacenes based on benzo[b]thieno[2,3-d]thiophene / quinoline or 1,8-napht... more Construction of new heteroacenes based on benzo[b]thieno[2,3-d]thiophene / quinoline or 1,8-naphthyridine systems using the Friedländer reaction
Tetrahedron, 2017
(Hetero)arylation of [1,2,4]triazolo[1,5-a]pyrimidine through the direct nucleophilic C-H functio... more (Hetero)arylation of [1,2,4]triazolo[1,5-a]pyrimidine through the direct nucleophilic C-H functionalization of the C-7 and C-5 positions has been implemented. The regioselective addition of a (het)aryl magnesium bromide to C-7 of 6-bromo-[1,2,4]triazolo[1,5-a]pyrimidine, followed by eliminative aromatization of the intermediate σ H-adducts, has afforded 7-(hetero)arylsubstituted [1,2,4]triazolo[1,5-a]-pyrimidines (the ܵ ே ு reaction, proceeding according to the "addition-elimination" scheme). A second treatment with a Grignard reagent has resulted in the C-5 σ H-adducts, which have been oxidized while being N-magnesium salts into [1,2,4]triazolo[1,5-a]pyrimidines, bearing various combinations of (hetero)aromatic substituents at C-5 and C-7 (the ܵ ே ு process, realizing via the "addition-oxidation" scheme). As a result of optical and electrochemical studies, the obtained compounds have proved to be promising luminescent dyes and push-pull systems.
Journal of fluorescence, Jan 31, 2015
Novel donor-π-acceptor dyes bearing the pyrimidine unit as an electron-withdrawing group have bee... more Novel donor-π-acceptor dyes bearing the pyrimidine unit as an electron-withdrawing group have been synthesized by using combination of two processes, based on the microwave-assisted Suzuki cross-coupling reaction and nucleophilic aromatic substitution of hydrogen. Spectral properties of the obtained dyes in six aprotic solvents of various polarities have been studied by ultraviolet-visible and fluorescence spectroscopy. In contrast to the absorption spectra, fluorescence emission spectra displayed a strong dependence from their solvent polarities. The nature of the observed long wavelength maxima has been elucidated by means of quantum chemical calculations. The electrochemical properties of these dyes have been investigated by using cyclic voltammetry, while their photovoltaic performance was evaluated by a device fabrication study. The experimental and calculation data show that all of the dyes can be regarded as potentially good photosensitizers for dye-sensitized solar cells.
Synthesis, 2021
The effect of chalcogenophosphoryl fragments on the anodic oxidation of 9-chalcogenophosphoryl-9,... more The effect of chalcogenophosphoryl fragments on the anodic oxidation of 9-chalcogenophosphoryl-9,10-dihydroacridines was studied in detail. The data of X-ray structural analyses, quantum chemical calculations, and cyclic voltammetry measurements obtained for these compounds provide an explanation of the observed features. The direct electrochemical phosphorylation of acridine was first carried out successfully.