Vol 89, No 12 (2019)
- Year: 2019
- Articles: 49
- URL: https://journals.rcsi.science/1070-3632/issue/view/13717
Article
Colloidal and Nanosized Catalysts in Organic Synthesis: XXIII. Reductive Amination of Carbonyl Compounds Catalyzed by Nickel Nanoparticles in a Plug-Flow Reactor
Abstract
Reductive amination of aldehydes and ketones with primary and secondary amines under catalysis with nickel nanoparticles supported on zeolite X, MgO, or activated carbon in the gas phase or in the gas-liquid system in a plug-flow reactor proceeds at atmospheric pressure of hydrogen with the formation of secondary or tertiary amines in high yield.
Synthesis of Cyclic Derivatives of Carbonyl Compounds of Furan Series
Abstract
Cyclic acetals of furan aldehydes (furfural, 5-hydroxymethylfuran-2-carbaldehyde and furan-2,5-dicarbaldehyde) and alcohols (ethylene glycol and 2-sulfanylethanol) were synthesized. The effect of the ratio of the starting reagents on the yield of acetals obtained was studied.
Synthesis, Structure, and Biological Activity of 4-R-4-Oxo-2-[2-(phenylamino)benzoyl]hydrazinylidene-N-hetarylbutanamides
Abstract
Decyclization of N′-[5-R-2-oxofuran-3(2H)-ylidene]-2-(phenylamino)benzohydrazides under the action of heterocyclic amines leads to the formation of N-hetaryl-4-R-4-oxo-2-[2-(phenylamino)benzoyl]hydrazinylidenebutanamides. Antinociceptive and anti-inflammatory activity of the obtained compounds was studied.
Synthesis and Halogenocyclization of 2-Allyloxyquinoline Derivatives
Abstract
Alkylation of 4,8-dimethyl- and 4,6,8-trimethylquinolin-2(1H)-one with allyl bromide in the presence of a base proceeds at the oxygen and nitrogen atoms with the predominant formation of the O-isomer. The reaction of 2-allyloxyquinolines with halogens leads to the formation of oxazolo[3,2-a]quinolinium salts. Structure of 1-bromomethyl-5,7,9-trimethyl-1,2-dihydro[1,3]oxazolo[3,2-a]quinolinium iododibromide was established by single crystal X-ray diffraction method.
Isoenthalpy Catalytic Effects of Pyridines in Reactions of Phenyloxyrane with N-Aroylbenzenesulfonamides
Abstract
Additive nature of the combined effect of the structure (X, Y substituents) and temperature on the rate and free activation energy has been established for the reactions of phenyloxirane with Y-substituted N-aroylbenzenesulfonamides catalyzed by X-substituted pyridines. The cross reaction series is isoenthalpic with respect to the structural effects. The mechanism of the catalytic process has been discussed.
Synthesis of New Fused Furo- and Thienopyridines
Abstract
A method was developed for the synthesis of new fused derivatives of pyrano[4,3-b]thieno(furo)-pyridine, namely 8,8-dimethyl-11-(2-furyl)-7,10-dihydro-8H-pyrano[3″,4″:5′,6′]pyrido[3′,2′:4,5]thieno(furo)[3,2-d]- pyrimidine-4(3H)-ones, from 2,2-dimethyltetrahydropyran-4-one. Optimal conditions for carrying out the cyclization reaction of ethyl {7,7-dimethyl-4-(2-furyl-3-cyano-7,8-dihydro-5H-pyrano[4,3-b]pyridin-2-yl]oxy}acetate into the corresponding amino ester were determined.
Reactions of 1-Alkyl-2-chloro-1H-indole-3-carbaldehyde with 4-Amino-5-alkyl(aryl)-4H-triazole-3-thioles
Abstract
The reaction of 1-alkyl-2-chloro-1H-indole-3-carbaldehydes with 4-amino-5-alkyl(aryl)-4H-1,2,4-triazole-3-thiols afforded new heterocyclic compounds, namely triazolo(thiadiazepino)indoles. Structure of the latter was established by single crystal X-ray diffraction method. This heterocyclic system is formed upon cyclization of the intermediate 5-alkyl-4-[indol-3-yl(methylideneamino)]-4H-1,2,4-triazole-3-thiols.
Synthesis of Stable σ-Adducts by Arylation of Quinazoline
Abstract
The reactions of quinazoline with 1,3,5-trimethoxybenzene, 3- and 4-methylbenzene-1,2-diamines, and 1-(4-methoxybenzylidene)-2-phenylhydrazine on heating in the presence of trifluoroacetic acid afforded the corresponding stable C–C σ-adducts.
Heat-Induced Reactions of 6-Bromo-, 6-Chloro-, and 6-(Methylsulfanyl)octafl uoroindane-5-thiols with Tetrafluoroethylene. Synthesis of Dodecafluoro-2H,3H,5H,6H,7H-indeno[5,6-b]thiophene
Abstract
Dodecafluoro-2H,3H,5H,6H,7H-indeno[5,6-b]thiophene has been synthesized as the major product of co-pyrolysis of 6-bromo-, 6-chlorooctafluoroindane-5-thiols, or bis(6-bromo-5-perfluoroindanyl)disulfane with tetrafluoroethylene under flow conditions at 400-625ºC, along with small amount of tetradecafluoro-1,2,3,5,6,7-hexahydro-s-indacene. Dodecafluoro-2H,3H,5H,6H,7H-indeno[5,6-b]thiophene formed in the reaction of 6-(meth-ylsulfanyl)octafluoroindane-5-thiol with tetrafluoroethylene at 420ºC has been isolated, and its structure has been confirmed by X-ray diffraction analysis. The schemes of the products formation involving intermediate radicals have been proposed.
Reactions of Benzylidene Chlorides with S-Methyl Diethylphosphinothioate
Abstract
S-Methyl diethylphosphinothioate reacted with benzylidene chlorides to give the corresponding aryl(chloro)methyl methyl sulfide and diethylphosphinoyl chloride. The product structure suggests initial attack of the methylsulfanyl group on the CH carbon atom of dichloromethylarene. Arenecarbothialdehyde dithioacetals and trimers and O,O-dialkyl[aryl(methylsulfanyl)methyl]phosphonates were synthesized.
New Tetrazole Tripodal Ligand Based on Triphenylphosphine Oxide
Abstract
A new tetrazole tripodal ligand, tris[2-(tetrazol-5-ylmethoxy)phenyl]phosphine oxide, has been obtained. Its structure in crystal and solutions has been elucidated by X-ray diffraction analysis as well as IR, Raman, and multinuclear (1H, 13C, 31P) NMR spectroscopy. Coordination properties of the polydentate ligand have been studied as exemplified by the complexation with lanthanum(III).
Metal Complexes of 2,9,16,23-Tetra-tert-butyl-3,10,17,24-tetranitrophthalocyanine with Lanthanides
Abstract
Metallization of 2,9,16,23-tetra-tert-butyl-3,10,17,24-tetranitrophthalocyanine or template condensation of 4-tert-butyl-5-nitrophthalodinitrile with chlorides of some lanthanides furnished the corresponding metal complexes. Their spectral properties were studied.
Synthesis and Luminescent Properties of Eu3+, Gd3+, and Tb3+ Complexes with Quinoline-4-carboxylic Acids
Abstract
New complex compounds LnL3·nH2O (n = 5–10) have been synthesized on the basis of Eu3+, Gd3+, and Tb3+ salts and quinoline-4-carboxylic acid derivatives obtained via the Pfitzinger reaction. Composition and structure of the ligands and the resulting complex compounds have been confirmed by NMR and IR spectroscopy, thermogravimetry, and complexometric titration. Europium complex with 1,2,3,4-tetrahydroacridine-9-carboxylic acid has exhibited efficient luminescence.
Luminescent Properties of Europium(III) Complexes with Quinaldic Acid and Sulfur–Containing Neutral Ligands
Abstract
The luminescent heteroligand complexes of europium(III) with quinaldic acid and sulfur-containing neutral ligands Eu(Quin)3∙D∙3H2O (Quin–quinaldic acid, D–dimethyl sulfoxide or dihexyl sulfoxide) and Eu(Quin)3∙3H2O have been obtained. Their composition and structure have been determined. The thermal and spectral-luminescent properties of the heteroligand europium(III) complexes have been studied. The quinaldate ion has been found to coordinate to the europium(III) ion as a bidentate ligand. The Stark structure of 5D0–7Fj (j = 0, 1, 2) transitions in the low-temperature luminescence spectra of the europium(III) complexes has been analyzed
Synthesis and Transport and Ionophoric Properties of α,ω-Diphosphorylated Azapodands: XII. Membrane Transport of Organic Acids by Diphosphorylated Diamines and Diazapodands
Abstract
Membrane transport of mono- and polyfunctional carboxylic acids mediated by phosphorylated diamines has been studied. The structure of complexes transferred through the membrane has been discussed; in some cases, a relation has been found between the efficiency of membrane transport of organic acid substrates and the structure of membrane carriers and their complexes with the acids. A correlation between the transmembrane flow and shift of some characteristic IR absorption bands (as well as change of their intensity) of the substrate–carrier complexes in comparison to the corresponding substrates and carriers has been estimated.
Chitosans: Thermochemical Study
Abstract
The physical and phase transitions of a series of chitosans differing in molecular weight and deacetylation degree have been revealed by means of differential scanning calorimetry, thermogravimetry, and mass spectrometry. The temperature ranges corresponding to the dehydration and thermolysis of the considered polymers have been determined. The devitrification temperature of the polymers has been recorded, and its two-parametric regression on the chitosans molecular weight and deacetylation degree has been found. The molecular weight of the polymer revealed stronger effect on the devitrification temperature in comparison with the deacetylation degree.
Sorption of Copper(II) Ions with Nanosized Magnesium Phosphate
Abstract
A new approach to the preparation of a nanosized sorbent based on magnesium phosphate has been developed. The patterns of copper(II) ions sorption with nanosized magnesium phosphate from aqueous solutions have been investigated. The sorption parameters have been determined, and the kinetics and mechanism of the processes have been elucidated. The high sorption ability of the nanoscale sorbent has been shown in comparison with existing sorbents based on magnesium phosphate.
Structure of the Li+ Ion Close Environment in Various Solvents
Abstract
The literature data on various methods for studying structural characteristics of the Li+ ion close environment in a number of oxygen-containing solvents were generalized. The coordination numbers of the Li+ cation, interparticle distances, and types of ionic association were discussed. The number of coordinated solvent molecules and the Li+–O distance in the first coordination shell are independent of the nature of the considered solvents.
Preparation of Nanosized α-Fe2O3 Using Mechanical Activation
Abstract
The processes occurring during the mechanical activation of a-Fe2O3 (hematite) in the presence of oleic acid in a centrifugal-planetary mill have been investigated. Mechanical activation for 10 h afforded hematite powder with particles size of 10–40 nm, as shown by means of X-ray diffraction analysis, FTIR spectroscopy, high-resolution transmission electron microscopy, and specific surface area measurements. Longer milling has led to mechanochemical transformation of hematite into Fe3O4 (magnetite).
SrO-Bi2O3-Fe2O3-Based Composites: Synthesis and Electrophysical Properties
Abstract
New composite solid electrolytes formed in the SrO–Bi2O3–Fe2O3 system have been studied. The total electrical conductivity of the composites synthesized via the solid-phase method increases with an increase in the Fe2O3 content, being of mixed ion-electronic nature. Dependence of the fraction of ionic conductivity on the composition has been established. The resulting materials have exhibited photocatalytic activity and are interesting as elements of electrochemical devices.
Synthesis of New 4,4a-Dihydroxanthones via [4+2]-Cycloaddition Reaction
Abstract
The effect of electronic properties of substituents in the reactants on the [4+2]-cycloaddition of 3-vinyl-chromen-4-ones (dienes) and N-vinylpyrrolidines (dienophiles) has been studied. The conditions determining the formation of 4,4a-dihydroxanthones or benzophenones as the major products have been found. The aromatization of 4,4a-dihydroxanthones via pyran ring opening has been interpreted by quantum chemical calculations. A wide series of new 4,4a-dihydroxanthone and benzophenone derivatives have been isolated.
Synthesis and Anticholinesterase Activity of 3-{[4-Methyl-3-(4-methylpiperazin-1-yl)]pent-1-en-1-yl}-4H-chromen-4-ones
Abstract
A procedure has been developed and optimized for the synthesis of 3-{[4-methyl-3-(4-methylpiperazin-1-yl)]pent-1-en-1-yl}-4H-chromen-4-ones (as dihydrochlorides) by an unusual version of the Morita–Baylis–Hillman reaction. A number of the title compounds with various substituents in the chromene fragment and their deamination products have been synthesized, and their inhibitory activity against butyrylcholinesterase has been studied.
Synthesis of Glass-Ceramics in Mixed Fluorozirconate–Phosphate Systems
Abstract
Fluorozirconate-phosphate glasses of the ZrF4–BaF2–NaPO3(LiPO3) and ZrF4–BaF2–LaF3–AlF3–LiPO3 systems doped with EuF3, ErF3, and NdF3 were studied by the differential-thermal (DTA) and X-ray diffraction (XRD) analysis, luminescence spectroscopy, scanning and transmission electron microscopy (SEM and TEM) methods. Addition of the phosphate component up to 20 mol % decreases the glass transition temperature and increases the glass stability to crystallization. Heat treatment in the range >Tg–Tc1 of glass transition and first maxima of crystallization temperatures causes crystallization of nanosized β-BaZrF6 particles. At LiPO3 (NaPO3) concentrations of more than 80 mol %, glasses containing a crystalline phase are formed during the synthesis process.
Synthesis of N-Derivatives of Cytisine, Anabasine, and Salsoline Alkaloids with Pharmacophore 3-Aminopyridine-2(1H)-one and 5-Methyl-7-phenyloxazole[5,4-b]pyridine Cycles
Abstract
The reaction of nucleophilic substitution of 2-chloro-N-(6-methyl-2-oxo-4-phenyl-1,2-dihydropyridin-3-yl)acetamide and 2-(chloromethyl)-5-methyl-7-phenyloxazolo[5,4-b]pyridine with cytisine, anabasine, and salsoline alkaloids has afforded the corresponding derivatives. Structure of the obtained compounds has been confirmed by means of 1H and 13C NMR spectroscopy.
Design, Synthesis, and Biological Evaluation of 1,2,4-Oxadiazole-Isoxazole Linked Quinazoline Derivatives as Anticancer Agents
Abstract
A series of novel 1,2,4-oxadiazole-isoxazole linked quinazoline compounds is designed, synthesized and screened for anticancer activity on four human cancer cell lines including MCF-7 (breast), A549 (lung), DU-145 (prostate), and MDA MB-231 (breast) by using MTT assay with etoposide used as a positive reference. All compounds demonstrate good to moderate anticancer activity and two compounds are found to be the most potent.
Synthesis and Serviceability of New Symmetric Bis-pyrazolone Metal Complex Acid Dyes
Abstract
Synthesis of new symmetric bis-pyrazolone acid dye and its 3d transition metal complexes is studied. Bis-pyrazolone is synthesized from (E)-6,6’-(ethene-1,2-diyl)bis(3-hydrazinylbenzenesulfonic acid) and ethyl ace-toacetate. The synthesized bis-pyrazolone is coupled with diazonium salt of 4-sulpho-2-aminophenol in alkaline medium targeting bis-pyrazolone ligand acid dye. Various metal complexes are obtained by treating a methanolic solution of metal salts with ligand acid dye in basic media. Structures of the synthesized ligand dye and its metal complexes are confirmed by UV-Vis, FTIR, and NMR spectra. The ligand acid dye and metal complex dyes demonstrate absorption in UV-Vis in the range of 400–600 nm. Ligand acid dye and its metal complexes demonstrate good to high value of light speed, washing fastness and rubbing fastness on leather.
Synthesis and Properties of Main-Chain Phosphorescent Polymer with Iridium Complex
Abstract
The main-chain phosphorescent polymers, PFCzIr(PhStz) and PFOIr(PhStz) with iridium complex (4-BrPhBt)2Ir(Pytz), are synthesized by the Suzuki polycondensation, in which the fluorene-carbazole and fluorene segments are used as a polymer backbone. The studied photoluminescent and electroluminescent properties demonstrate good overlap of the emission spectra of poly(fluorene-carbazole) (PFCz) or polyfluorene (PFO) host and the absorption spectra of the iridium complex guest that meets requirements for the efficient Forster transfer from the host polymer to the iridium complex in polymers. With the increase of the content of iridium complex, the host emission intensity decreases, while the guest emission intensity gradually increases. As compared with PFOIr(PhStz), host-guest system in PFCzIr(PhStz) is more efficient in Forster energy transfer, and the photoluminescence and electroluminescence properties are more sound. Among all polymers, PFCzIr(PhStz) 5.0 demonstrates the best performance in electroluminescence, its fluorescence quantum is 22.74%. The devices fabricated from PFCzIr(PhStz)5.0 exhibit yellow-red emission with a maximum brightness of 1568 cd/m2 at 14 V, luminous efficiency and power efficiency reach 6.24 cd/A and 2.45 lm/w.
Cu(I)-Catalysis of One-Pot Synthesis of Some Novel Regioselective Isoxazole-Benzimidazole Hybrids and Their In Vitro Anti-Cancer Evaluation
Abstract
Regioselective synthesis of some novel isoxazole-benzimidazole hybrids in high yields via Cu(I)-catalyzed tandem one-pot reaction of aromatic aldehydes with 1-prop-2-ynylbenzimidazole is developed. Structures of the synthesized compounds are confirmed by NMR and mass spectra. All the synthesized compounds have been tested for their in vitro anticancer activity against three human cancer cell lines including ACHN, MCF-7, and A375. Among these, three compounds demonstrate anticancer activity (0.54 to 4.21 µM) higher than the positive control doxorubicin.
Zn(II) Complexes with Quinoline Supported Amidate Ligands: Synthesis, Fluorescence, and Catalytic Activity
Abstract
Zn(II) complexes of N-(quinolin-8-yl)picolinamide (HL1) (1) and N2,N6-di(quinolin-8-yl)pyridine-2,6-dicarboxamide (H2L2) (2) have been synthesized by deprotonation of the ligands and characterized by IR, NMR, and Single crystal X-ray crystallography. The mononuclear [Zn(L1)2] (3) and homodinuclear [Zn2(L2)2] (4) complexes are characterized by distorted octahedral geometries stabilized by hydrogen bonding and weak π···π interaction. The complexes demonstrate intense fluorescence bands in comparison with their corresponding ligands with well-distinguished intensity. The complexes act as efficient catalysts in various transesterification reactions. Among those, the best results have been achieved with complex 3 in conversion of 4-nitrophenylacetate into methyl acetate within 3 h.
Design, Synthesis, and Anticancer Activity of 1,2,3-Triazole Likned Thiazole-1,2-isoxazole Derivatives
Abstract
A series of novel 1,2,3-triazole linked thiazole-1,2-isoxazole derivatives has been designed, synthesized and characterized by 1H and 13C NMR, and mass spectral analysis. The compounds have been tested for their anticancer activity towards MCF-7 (breast cancer), A549 (lung cancer), Colo-205 (colon cancer), and A2780 (ovarian cancer) by using the MTT method using etoposide as the reference. Most of the tested compounds demonstrate good to moderate activity against all cell lines. The compounds 14b, 14e, 14g, and 14h are characterized by inhibitory activity stronger than that of etoposide.
Chemical Preparation of Nanostructures of Ni(II), Pd(II), and Ru(III) Oxides by Thermal Decomposition of New Metallic 4-Aminoantipyrine Derivatives. Catalytic Activity of the Oxides
Abstract
This article is focused on preparation of Ni(II), Pd(II) and Ru(III) oxides in the nanoscale form from the complexes of N,N,N,N-tetradentate Schiff base with Ni(II), Pd(II) and Ru(III). The complexes have been synthesized and characterized by elemental analyses, magnetic susceptibility, molar conductivity, 1H and 13C NMR, FT-IR, UV-Vis, mass, and TG-DTG analysis. The accumulated data indicate that the central metal ion in the complexes is coordinated with four nitrogen atoms of the imino and amino groups. The complexes are characterized by a 1 : 1 metal : ligand ratio and octahedral geometry except for Pd(II) complex which has a tetradentate structure. The complexes have been used as precursors for NiO, PdO and RuO2 preparation of NPs by thermal decomposition at 600°C in the static air. Formation of the NPs is discussed in terms of FTIR, XRD, SEM, and TEM analyses data. The rate of catalytic decoloration activity of Malachite green dye under the action of metal oxides is considered. The dye has been successfully decolorized in presence of the NPs at room temperature.
Synthesis and Antibacterial Activity of Novel 3-N-Substituted 1,8-Naphthyridin-2(1H)-ones
Abstract
Synthesis of novel N-protected and unprotected 3-N-substituted 1,8-naphthyridin-2(1H)-ones with potential inhibiting activity of penicillin-binding protein 6 (PBP6) has been developed. The synthesis is designed around a Buchwald–Hartwig crosscoupling of various 3-bromo-6-substituted-1,8-naphthyridin-2(1H)-ones with two different functionalized anilines. According to the preliminary antibacterial evaluation, the products 9b–9d and 10b–10d have demonstrated high inhibiting activity against spore germination of Staphylococcus aureus (gram positive) and Escherichia coli (gram negative). The molecular docking procedure has denoted the probable interactions of the synthesized compounds 9b–9d and 10b–10d with the target protein.
Kumada Cross Coupling Reaction for the Synthesis of Quinazoline Derivatives, Evaluation of Their Antibacterial Activity and Docking Studies
Abstract
A series of C7-substituted-2-morpholino-N-(pyridin-2-ylmethyl)quinazolin-4-amine derivatives 3a–3t were synthesized by using Nickel catalyzed Kumada cross coupling reaction. The structure of the key intermediate 2 was assigned using 2D COSY and 2D NOESY correlation spectrum. All the target compounds were characterized and tested for their antibacterial activity against Gram-positive organisms such as Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis, and Gram-negative organisms such as Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumonia. The results indicated that compounds 3g–3m exhibited potent antibacterial activity with MIC values ranging from 1.17 to 4.68 μg/mL. These results are expected to be of help in understanding the structure activity relationship and further enable us to design novel antibacterial agents. Molecular docking of Escherichia coli Biotin Carboxylase (EcBC) enzyme was also performed in order to study the interactions of the synthesized compounds.
Efficient Synthesis of Phenoxathiines via the Cascade C–H Hydroxylation–C–S Coupling–C–O Cyclization Reaction
Abstract
The ligand-free and simple cascade C–H hydroxylation–C–S coupling–C–O cyclization reaction has been used as the synthetic approach to disulfides and o-chloro-iodobenzenes using CuI as a catalyst. This approach provides an easy and convenient method of synthesis of phenoxathiin derivatives.
Application of the Cleavable Isocyanide in Efficient Approach to Pyroglutamic Acid Analogues with Potential Biological Activity
Abstract
Two efficient procedures have been developed for the synthesis of pyroglutamic acid analogues 28, 29, and 34. According to the first method the Ugi (4C3C) reaction is followed by a post-transformation reaction, and the second method involves the Michael addition reaction. The present methodologies demonstrate the applicability of 1-(2,2-dimethoxyethyl)-2-isocyanobenzene (15) as a cleavable isocyanide in the Ugi/ post-transformation reaction and a strong nucleophile in the Michael addition reaction. The framework of pyroglutamic acid analogues has been constructed by the selective cleavage of the C-terminal amide bond and nucleophilic addition to the activated α,β-unsaturated carbonyl group.
Synthesis and Optical Properties of New S-Derivatives of 5,5′-(1,4-Phenylene)bis(4H-1,2,4-triazole-3-thiol) and 5,5′,5″-(Benzene-1,3,5-triyl)tris(4H-1,2,4-triazole-3-thiol)
Abstract
A simple one-pot synthetic method for novel S-alkenyl and propargyl derivatives of 5,5′-(1,4-phenylene)-bis(4H-1,2,4-triazole-3-thiol) and 5,5′,5″-(benzene-1,3,5-triyl)tris(4H-1,2,4-triazole-3-thiol) has been developed. Absorption and luminescence properties of the synthesized compounds have been estimated, and the fluorescence quantum yields have been determined.
Synthesis, Two-Photon Absorption, and Cellular Imaging of Two Curcumin Derivatives
Abstract
Two curcumin derivatives, 1,7-bis(4-bromoethyloxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione (1) and 1,7-bis(4-bromobutyloxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione (2), have been conveniently synthesized and their structures characterized by 1H NMR and mass spectra, and single crystal X-ray diffraction measurements. Single-photon and two-photon fluorescence properties have been studied. The calculated two-photon absorption cross-sections for both compounds by quantum chemical method are as high as 358 and 326 GM, respectively. Two-photon fluorescent imaging of MCF-7 cells labeled with the compound 1 indicates its potential application as a biological fluorescent probe.
Photoconductivity, Antioxidant, and Antimicrobial Activities of Some Acenaphthenequinone Derivatives
Abstract
Photoconductive acenaphthenequinone derivatives have been synthesized by a one-pot process of acenaphthenequinone with different aromatic hydrazides (nicotinic, isonicotinic, 2-thiophenecarboxylic, 2-furoic, 3-methoxybenzoic, 3-hydroxy-2-naphthoic, and 2,4-dihydroxybenzoic). Their structures are supported by elemental analysis, 1H and 13C NMR, IR, and MS spectroscopy. Photoelectrochemical (PEC) measurements reveal that the compounds demonstrate photoresponse upon illumination by light of intensities 1000 and 10000 W/m2. The photoconductivity behaviors of the derivatives is enhanced in the presence of electron donor groups attached to the aromatic ring. Thereby, these products may be used in material devices as organic thin film transistors, on/off sensors, etc. The antioxidant activity of the products has been tested by DPPH radical scavenging method in vitro, indicates their significant potential. Antimicrobial activity of the derivatives has been estimated by minimum inhibitory concentration (MIC, mg/mL) using the micro-broth dilution method. The compounds are moderately active against some Gram positive bacteria and Candida albicans and completely inactive against Gram negative bacteria tested.
LiCl-Accelerated Nickel Catalyzed Cross-Coupling of Aryl Tosylates with the Aryl Grignard Reagents
Abstract
A mild coupling reaction catalyzed by Ni(acac)2-L4 has been studied. The catalyst acts efficiently in the reaction of biaryl coupling between various electrophiles and common or functionalized aryl Grignard reagents with high functional group tolerance. The study demonstrates that LiCl acts as an essential component in efficient cross-coupling by accelerating reduction of Ni(II) to Ni(0). The new catalytic system for selective couplings of aryl tosylates with aryl chlorides has been developed.
Letters to the Editor
Reactions of Chloroethynylphosphonates with 2-Aminoquinoline and 1-Aminoisoquinoline
Abstract
The reactions of chloroethynylphosphonates with 2-aminoquinoline and 1-aminoisoquinoline proceeded chemo- and regioselectively to form novel fused tricyclic compounds with pharmacophore groups, namely dialkyl-(imidazo[1,2-a]quinolin-2-yl)- and (imidazo[2,1-a]isoquinolin-2-yl)phosphonates in high yield.
Selected articles originally published in Russian in Rossiiskii Khimicheskii Zhurnal (Russian Chemistry Journal)
C–O, C–S, C–N, and C–C Bond Formation at the Periphery of the Macrocycle during Chemical Modification of Phytochlorins: Key Methods and Synthetic Applications
Abstract
The main methods of C-O, C-S, C-N, and C-C bond formation at the periphery of the macocrocycle during chemical modification of phytochlorins in the synthesis of biologically active substances and model compounds and in the independent synthesis of natural chlorins are reviewed.
Еxcitation Energy Relaxation Processes Involving Chlorophyll Molecules In Vitro: Solutions and Self-Organized Nanoassemblies
Abstract
The review presents the main results obtained by the Belorussian scientific school of Acad. G.P. Gurinovich and his followers in the in the research on the spectral kinetic properties and photonics of pigment-pigment interactions of chlorophyll and its close analogs in vitro (from highly concentrated solutions to structurally organized heterogeneous nanoassemblies of various morphology), as well as on the interactions of multiporphyrin nanoassemblies with molecular oxygen. The adequacy of various theoretical models that describe the primary processes of photosynthesis (electronic excitation energy transfer and photoinduced charge transport) at short interchromophore distances, considering the properties of the medium and the conformational dynamics of interacting subunits, is substantiated. Application-oriented aspects concerning the use of multicomponent nanostructures on the basis of photostable tetrapyrrole compounds with controllable electron-transport properties and conformational mobility for the development of element base in molecular electronics, photonics, medicine, and nanobiotechnology are considered in brief.
Boron Dipirrins: Mechanism of Formation, Spectral and Photophysical Properties, and Directions of Functionalization
Abstract
Boron dipyrrins (Bodipy) are unique complexes occupying an intermediate position between classical coordination and organometallic compounds. The enormous interest of researchers from all over the world to the compounds of this class has by now provided an endless stream of publications that requires generalization. Existing reviews and original publications do not fully cover the structural diversity of Bodipy and their possible applications in engineering, medicine, analytical chemistry, optics, photonics, etc. In this paper, w e present the results, mainly of our own research, which for the first time allowed us to establish the physicochemical principles of the formation of Bodipy (the reasons for the low rates of complexation of ligands with boron trifluoride), changes in the spectral and photophysical properties of alkylated Bodipy complexes with the separation of contributions from universal and specific solvation, and examples of functionalization of inorganic and organic polymer materials based on Bodipy of different structures. Examples of the current team’s Bodipy research in different practical areas are presented.
The Problem of Preserving the Self-Color of Linen Textiles
Abstract
Issues of preservation of the self-color of gray linen fabrics were discussed. Textiles preparation variants and their influence on the color characteristics of flax were considered. For preserving the chromophoric structure of lignin, enzymatic and plasma treatment methods were proposed.
Plasticization Kinetics and Supramolecular Structure of the Cellulose Nitrates Obtained from Different Cellulose-Containing Raw Materials
Abstract
The kinetics of plasticization and the supramolecular structure of the cellulose nitrates obtained from wood, flax, and cotton celluloses were studied. These studies are essential for finding alternative sources of cellulose-containing raw materials for cellulose nitrate production with a view to overcoming the acute cotton scarcity problem. A precondition to the processing of cellulose nitrates is their plasticizability by semi-volatile low-molecular-weight compounds, and the quality of the resulting products is directly affected by the plasticization rate.
Metal Sorption by Materials with a Mobile Phase of Extractants
Abstract
Data on sorption of rare, noble, radioactive, and nonferrous metals from aqueous solutions by impregnates and TVEXs were analyzed. These are materials combining the properties of sorbents and extractants and differing in the production method. Their distinctive feature is that the extractant is not chemically bonded to the solid support, which is responsible for high kinetic characteristics of sorption processes involving these materials, favorably comparing with conventional sorbents. As a mobile phase to be deposited on the carrier (mainly polymeric) in the case of impregnates or to be introduced during synthesis of TVEXs served organophosphorus extractants, amines, quaternary ammonium bases, etc. Information regarding the effect of various parameters (solution acidity, metal concentration, phase ratio, temperature, and concentration of impurity elements) on separating capability and metal sorption capacity and kinetics was provided for this type of materials. Methods used for stabilizing the properties of impregnates with the view to minimize the extractant loss during application were considered.
Adsorption of Anionic Metallophthalocyanines on Submicron Chitosan-Sulfate Particles in Aqueous Dispersions
Abstract
The kinetic and capacity of the anionic metallophthalocyanines adsorption on the submicron chitosan-sulfate particles in aqueous dispersions were examined. Phthalocyanine dyes differing in the molecular size, as well as in the number and nature of the anionic groups, were used as model adsorbates. The suitability of well-known mathematical models for describing the adsorption kinetics was analyzed. Using the graphical testing method it was shown that the adsorption kinetics data are best fitted by the Ho-McKay pseudo-second-order model. The maximum adsorption is independent of the molecular size and tends to increase with decreasing solubility of the dye under the experimental conditions. It was proved that sulfonated metallophthalocyanines in the adsorption process partially replace the sulfate ions, thereby acting as polyanionic cross-linkers in the chitosan particle structure. Comparative evaluation of the dye desorption rates in the phosphate buffer was carried out.