scholarly journals Search of new luminophores with predetermined physicochemical and chemical properties ХVІ. N-arylmethylene- and N–hetarylmethylene- substituted for polyvinylamine

2018 ◽  
Keyword(s):  
Formic Acid ◽  
Chemical Properties ◽  
Transformation Products ◽  
Aldehyde Group ◽  
Short Wave ◽  
Low Grade ◽  
Hard State ◽  
Short Wave Region ◽  
Similar Solutions ◽  
Derivatives Of

Investigation of transformation of polyacrylamide (PAA) in the polyvinylamine (РVAm) the reaction of Hofmann and further transformation of NH2-groups polymer by the Leuckart—Wallach reaction. The reliability of the transformation of PAA into PVAm is confirmed by the reaction of diazotization and acylation of the samples obtained by PVA and by the color reactions of the PVAm transformation products. The structure of PVAm is also confirmed by data from IR spectroscopy and pH-metric titration. The product obtained is a vinylamine copolymer (up to 80%), acrylamide and acrylic acid. Syntheses of N-arylmethylene- and N-hetarylmethylene substituted PVAm, is carried out by the reduction alkylating of NH2-groups of РVAm by aromatic and heterocyclic aldehydes [5‑(4‑chlorophenyl)-2-(4-formylphenyl)oxazol-1,3, 5-(4-methoxyphenyl)-2-(4-formylphenyl)oxazol-1,3, 5‑(4‑methylphenyl)-2-(5-formylfuryl-2)oxazol-1,3, 5-(4-methoxyphenyl)-2-(5-formylfuryl-2)oxazol-1,3, 3,5-diphenyl-1-(4-formylphenyl)-2-pyrazoline, pyrene-3-aldehyde, possessing luminescence, in presence formic acid. The indicated derivatives of PVAm are got also by successive formation with NH2-groups of elementary links of grounds of Schiff and reduction of them NaBH4. The derivatives of PVAm containing N-arylmethylene and N‑hetarylmethylene groups [...–CH2−CH(NH−CH2−Ar) – ... and ... –CH2−CH(NH−CH2−Het) – ...), respectively], low-grade in water, nonpolar organic, partially soluble in polar solvents and readily soluble in acid solutions.The got standards of modified PVAm, containing elementary links of …–СН2−СН(NH−CH2−Ar)–… and ...–СН2−СН(NH−CH2−Het)–..., luminesce both in the hard state and in solutions. IR-specta (hard state) РVAm and modified foods is studied, spectrums of absorption and luminescence of N-arylmethylene- and N‑hetarylmethylene substituted for PVAm, (in solutions of the mixed solvent is ethyl acetate - formic acid). The fluorescence maxima of PVAm derivatives are shifted to the short-wave region in comparison with similar solutions for initial aldehydes due to the reduction of the chromophore chain through the replacement of the aldehyde group with methylene.

scholarly journals Search for new luminophores with predetermined physicochemical and chemical properties. XIV.N-Arylmethylene- and N-hetarylmethylene derivatives of poly (3‒aminopropene)

2020 ◽  
Keyword(s):  
Formic Acid ◽  
Mixed Solvent ◽  
Spectral Characteristics ◽  
Chemical Properties ◽  
Specific Effect ◽  
Heterocyclic Aldehydes ◽  
Derivatives Of ◽  
Harsh Conditions ◽  
Low Solubility ◽  
And Chemical Properties

The possibility of creating polymers with fluorescence, derivatives of poly (3-aminopropene) (PAP) by alkylation of amino groups with aromatic or heterocyclic aldehydes by Leykart-Wallach reaction with own fluorescence was investigated. Synthesis of N-alkylated PAP derivatives was performed by sequential conversion: acrylamide → PAA (Mν = 100 kDa) → PAP → alkylated PAP. Due to the impossibility of using LiAlH4 to reduce the amide groups of polyacrylamide to amine due to the low solubility of PAA in the non-aqueous (diethyl ether, tetrahydrofuran, etc.) solvents, the reduction of PAA by other reducing agents was optimized. It was found that the best conditions for the reduction of amide groups of PAA to amine - acetic acid - dioxane as a solvent and NaBH4 (suspended in anhydrous 1,4-dioxane) as a reducing agent. According to IR spectroscopy, the products obtained are copolymers of 3-aminopropene (the main amount of elementary units), acrylamide and acrylic acid. To modify the structure of the obtained polymer, the Leuckart-Wallach reaction was used, where the following aldehydes having luminescence were selected: pyrene-3-aldehyde, 2-hydroxy-1-naphthaldehyde, anthracene-9-carbaldehyde, and 3.5 phenyl-1-(4-formylphenyl)-2-pyrazoline. To obtain N-Ar/Het-methylene derivatives, a mixture of PAP, aldehyde and 98% formic acid was heated under harsh conditions (6 hours, glycerol bath), isolated and purified. The obtained modified samples of polymers are intensely fluorescent both in the solid state and in the form of solutions, which indicates the successful passage of the Leykart-Wallach reaction. Spectral characteristics were obtained for solutions in a mixed solvent – ethyl acetate – formic acid (9 : 1). For both the original aldehydes and the copolymers in the mixed solvent used, the spectral fluorescence curves lose their oscillatory structure, probably due to the specific effect of the mixed solvent on the phosphor molecules (for the original aldehydes) and the side methylamino-N-arylmethylene - […СН2-СН(СН2-NH-CH2-Ar)- …] and methylamino-N-getarylmethylene […-СН2-СН(СН2-NH-CH2-Het)-…] groups both in the ground and in the excited state, and for polymers of inhomogeneity of the medium with local polarity zones.

scholarly journals Lignans of Sesame (Sesamum indicum L.): A Comprehensive Review

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 883
Author(s):  
Mebeaselassie Andargie ◽  
Maria Vinas ◽  
Anna Rathgeb ◽  
Evelyn Möller ◽  
Petr Karlovsky
Keyword(s):  
Biological Activities ◽  
Chemical Properties ◽  
Transformation Products ◽  
Extensive Literature ◽  
Controversial Issues ◽  
Sesame Seeds ◽  
Historical Texts ◽  
Health Promoting ◽  
Processed Products

Major lignans of sesame sesamin and sesamolin are benzodioxol--substituted furofurans. Sesamol, sesaminol, its epimers, and episesamin are transformation products found in processed products. Synthetic routes to all lignans are known but only sesamol is synthesized industrially. Biosynthesis of furofuran lignans begins with the dimerization of coniferyl alcohol, followed by the formation of dioxoles, oxidation, and glycosylation. Most genes of the lignan pathway in sesame have been identified but the inheritance of lignan content is poorly understood. Health-promoting properties make lignans attractive components of functional food. Lignans enhance the efficiency of insecticides and possess antifeedant activity, but their biological function in plants remains hypothetical. In this work, extensive literature including historical texts is reviewed, controversial issues are critically examined, and errors perpetuated in literature are corrected. The following aspects are covered: chemical properties and transformations of lignans; analysis, purification, and total synthesis; occurrence in Seseamum indicum and related plants; biosynthesis and genetics; biological activities; health-promoting properties; and biological functions. Finally, the improvement of lignan content in sesame seeds by breeding and biotechnology and the potential of hairy roots for manufacturing lignans in vitro are outlined.

scholarly journals Synthesis of monoketo and monohydroxy eicosanoic acids and esters with substituents at odd-numbered (3-13) carbons

2002 ◽  
Vol 67 (7) ◽  
pp. 473-480 ◽  
Author(s):  
Hulya Çelik
Keyword(s):  
Nmr Spectroscopy ◽  
High Purity ◽  
1H Nmr Spectroscopy ◽  
Methyl Esters ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Keto Acids ◽  
Physical And Chemical ◽  
Derivatives Of ◽  
And Chemical Properties

In this study, monoketo and monohydroxy eicosanoic acids and their methyl esters with the position of the substituent on odd numbered carbon atoms from 3 to 13 were synthesized with high purity. Furthermore, the semicarbazone and anilide derivatives of the obtained keto acids were prepared. They were characterized by TLC, IR and 1H-NMR spectroscopy and their physical and chemical properties were established.

scholarly journals Optimization of the observation of postpartum pyo-inflammatory diseases in patients after vacuum-aspiration using the method of fluorescent spectroscopy

2018 ◽  
Vol 22 (1) ◽  
pp. 156-159
Author(s):  
O.V. Bulavenko ◽  
L.R. Ostapiuk ◽  
V.O. Rud ◽  
A.S. Voloshinovskii ◽  
T.S. Maliy
Keyword(s):  
Fluorescence Spectroscopy ◽  
Inflammatory Diseases ◽  
Uterine Cavity ◽  
Short Wave ◽  
Maternity Hospital ◽  
The State ◽  
Optimal Time ◽  
Vacuum Aspiration ◽  
Manual Vacuum Aspiration ◽  
Short Wave Region

The growth of the frequency of postpartum purulent-inflammatory diseases requires the development of new approaches to their early diagnosis and treatment. The purpose of the study is to choose the optimal time for manual vacuum aspiration in patients with postpartum endometritis and to control the state of patients after it, using the method of fluorescence spectroscopy. The results of treatment of 392 patients who were on inpatient treatment in the gynecological department №2 of the City Clinical Maternity Hospital №2 were analyzed. Of these, 120 patients were selected for the diagnosis of which, in addition to the standard algorithm, the method of fluorescence spectroscopy was included. Manual vacuum aspiration was performed in 96 cases (80,0%). In 15% of patients, after vacuum-aspiration of the uterine cavity, blood serum tests using the method of fluorescence spectroscopy were carried out in dynamics. In 92,8% of them, an increase in fluorescence intensity and a shift of lmax in the short-wave region was observed, which was a reliable sign of improving the condition of the patients. Thus, the improvement of the state of patients after vacuum aspiration was confirmed at the appropriate level, using the method of fluorescence spectroscopy, which is a reliable method of diagnostics of postpartum purulent-inflammatory diseases.

scholarly journals Method of obtaining and studying the optical properties of carbon quantum dots.

2019 ◽  
Vol 19 (3) ◽  
pp. 226-229
Author(s):  
S.D. Bardasevska ◽  
I.M. Budzulyak ◽  
S.I. Budzulyak ◽  
B.I. Rachiy ◽  
R.V. Ilnytskyi ◽  
...  
Keyword(s):  
Raw Materials ◽  
Wavelength Region ◽  
Short Wave ◽  
Carbon Quantum Dots ◽  
Long Wavelength ◽  
Plant Raw Materials ◽  
Wave Region ◽  
Exciton Mechanism ◽  
Short Wave Region ◽  
Kinetics Of

The proposed method of synthesis of CQDs on the basis of nanoporous carbon obtained from plant raw materials. It is established that in the short-wave region a band is registered, which is due to the exciton mechanism of recombination, whereas in the long-wavelength region it is related to the state of defects. The kinetics of PL extinction is not strictly exponential, which most likely indicates the distributed nature of fading from individual emitters.

scholarly journals Mathematical modeling of a swirling jet in applications to low-emission combustion of low-grade fuels

2021 ◽  
Vol 23 (3) ◽  
pp. 308-317
Author(s):  
Usama J. Mizher ◽  
Peter A. Velmisov
Keyword(s):  
Carbon Dioxide ◽  
Natural Gas ◽  
Combustion Chamber ◽  
Negative Impact ◽  
Numerical Study ◽  
Combustion Process ◽  
Theoretical Data ◽  
Modern Society ◽  
Low Grade ◽  
Similar Solutions

Abstract. The search for new solutions in the field of energy, preventing negative impact on the environment, is one of the priority tasks for modern society. Natural gas occupies a stable position in the demand of the UES of Russia for fossil fuel. Biogas is a possible alternative fuel from organic waste. Biogas has an increased content of carbon dioxide, which affects the speed of flame propagation, and a lower content of methane, which reduces its heat of combustion. However, the combined combustion of natural gas and biogas, provided that the mixture of fuel and oxidizer is well mixed, can, on the one hand, reduce the maximum adiabatic temperature in the combustion chamber of power boilers at TPPs, and, on the other, increase the stability of biogas combustion. For the combined combustion of natural gas and biogas in operating power boilers, it is necessary to reconstruct the existing burners. For a high-quality reconstruction of burners capable of providing stable and low-toxic combustion of fuel, it is important to have theoretical data on the combustion effect of combustion of combinations of organic fuels on the temperature distribution in the combustion zone and on its maximum value. In this paper, self-similar solutions of the energy equation for axisymmetric motion of a liquid (gas) in a model of a viscous incompressible medium are obtained. Basing on them, a stationary temperature field in swirling jets is constructed. A set of programs based on the ANSYS Fluent software solver has been developed for modeling and researching of thermal and gas-dynamic processes in the combustion chamber. On the basis of the k - ϵ (realizable) turbulence model, the combustion process of a swirling fuel-air mixture is simulated. The results of an analytical and numerical study of the temperature and carbon dioxide distribution in the jet are presented.

scholarly journals Synthesis and Anticancer Activity of CDDO and CDDO-Me, Two Derivatives of Natural Triterpenoids

Molecules ◽  
2019 ◽  
Vol 24 (22) ◽  
pp. 4097 ◽  
Author(s):  
Rebecca Borella ◽  
Luca Forti ◽  
Lara Gibellini ◽  
Anna De Gaetano ◽  
Sara De Biasi ◽  
...  
Keyword(s):  
Biological Effects ◽  
Chemical Properties ◽  
Cell Types ◽  
Telomerase Activity ◽  
Culture Cell ◽  
Protease Inhibition ◽  
Mitochondrial Functions ◽  
Anti Inflammatory ◽  
Apoptotic Pathways ◽  
Derivatives Of

Triterpenoids are natural compounds synthesized by plants through cyclization of squalene, known for their weak anti-inflammatory activity. 2-cyano-3,12-dioxooleana-1,9(11)-dien-28-oic acid (CDDO), and its C28 modified derivative, methyl-ester (CDDO-Me, also known as bardoxolone methyl), are two synthetic derivatives of oleanolic acid, synthesized more than 20 years ago, in an attempt to enhance the anti-inflammatory behavior of the natural compound. These molecules have been extensively investigated for their strong ability to exert antiproliferative, antiangiogenic, and antimetastatic activities, and to induce apoptosis and differentiation in cancer cells. Here, we discuss the chemical properties of natural triterpenoids, the pathways of synthesis and the biological effects of CDDO and its derivative CDDO-Me. At nanomolar doses, CDDO and CDDO-Me have been shown to protect cells and tissues from oxidative stress by increasing the transcriptional activity of the nuclear factor (erythroid-derived 2)-like 2 (Nrf2). At doses higher than 100 nM, CDDO and CDDO-Me are able to modulate the differentiation of a variety of cell types, both tumor cell lines or primary culture cell, while at micromolar doses these compounds exert an anticancer effect in multiple manners; by inducing extrinsic or intrinsic apoptotic pathways, or autophagic cell death, by inhibiting telomerase activity, by disrupting mitochondrial functions through Lon protease inhibition, and by blocking the deubiquitylating enzyme USP7. CDDO-Me demonstrated its efficacy as anticancer drugs in different mouse models, and versus several types of cancer. Several clinical trials have been started in humans for evaluating CDDO-Me efficacy as anticancer and anti-inflammatory drug; despite promising results, significant increase in heart failure events represented an obstacle for the clinical use of CDDO-Me.

Hydroxycinnamoyl: Coenzyme A Transferase Involved in the Biosynthesis of Kaempferol-3-(p-coumaroyl Triglucoside) in Pisum sativum

1977 ◽  
Vol 32 (9-10) ◽  
pp. 765-768 ◽  
Author(s):  
Marie H. Saylor ◽  
Richard L. Mansell
Keyword(s):  
Coenzyme A ◽  
Chemical Properties ◽  
Acyl Donor ◽  
Coumaric Acid ◽  
Enzyme Preparations ◽  
Naturally Occurring ◽  
Enzymatic Formation ◽  
Derivatives Of ◽  
Acid Esters ◽  
And Chemical Properties

Abstract The major flavonoids of Pisum are derivatives of kaempferol and quercetin, including both tri-glucosides and acylated triglucosides in which the acyl group is p-coumaric acid. Although hydroxy-cinnamic acid esters of flavonoids are common pigments in many plants, neither the enzymes nor the precursors involved in their biosynthesis have been demonstrated. We report here that crude enzyme preparations extracted from peas catalyze the transfer of the p-coumaroyl moiety of p-coumaroyl: Coenzyme A to kaempferol-3-triglucoside forming kaempferol-3-(p-coumaroyl triglucoside) as the acylated product. The reaction product has been vigorously shown to be identical to the naturally occurring kaempferol-3-(p-coumaroyl triglucoside) in both chromatographic and chemical properties. The enzymatic formation of the acylated derivative occurred only minimally when incubated with the cofactors required for carboxyl group activation (ligase) and maximally when incubated with p-coumaroyl : Coenzyme A as the acyl donor.

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