Odesa National University Herald. Chemistry最新文献

{"title":"INFLUENCE OF BIMETALLIC COMPLEXES GERMANY (IV) AS MODIFIERS OF UNSATURATED OLIGOESTER ON THE KINETICS OF ITS COPOLYMERIZATION WITH METHYLMETHACRYLATE","authors":"O. O. Kiose, S. M. Savin, I. Seifullina, O. E. Martsinko, O. A. Chebanenko","doi":"10.18524/2304-0947.2021.4(80).250928","DOIUrl":"https://doi.org/10.18524/2304-0947.2021.4(80).250928","url":null,"abstract":"The possibility of using a number of bimetallic complexes of germanium (IV) - zinc / cobalt (II) / nickel (II) / cuprum (II) with hydroxycarboxylic acids as modifiers of unsaturated oligoester in the processes of its copolymerization with methyl methacrylate has been investigated. The modification was carried out by adding the corresponding complex to the reaction mixture during the polycondensation of maleic and phthalic anhydride with ethylene glycol at 175 °C. The kinetics of copolymerization at the initial stages was studied by dilatometry at temperatures from 50 °C to 60 °C. It has been shown that the modified polyglycolmalenatephthalate with the studied complexes can significantly increase the rate and reduce the temperature coefficient of the reaction during its copolymerization with methyl methacrylate. The advantages of the studied coordination compounds as modifiers in comparison with unmodified systems and 1,10-phenanthroline have been proved. The effect of the modifier (1,10-phenanthroline), depending on its content in the modified polyglycolmalenatephthalate, on the kinetic characteristics of copolymerization with methylmethacrylate in the range from 0 to 0.5 mol/L was investigated. The calculations of the influence of the temperature coefficient of reaction on the maximum allowable diameter on the example of a spherical sample when reaching a critical temperature of 90 0C for non-isotremic copolymerization processes. Physico-mechanical characteristics have been studied and it has been shown that the addition of a modifier does not significantly change them.  In addition, germanium (IV) compounds retain a higher oxidation state, which makes it possible to use the finished polymer product as a biological material for special purposes. The proposed methods can be used to improve the characteristics of semi-finished products in the industrial production of copolymer products without significant changes in the technological process.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"55 15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91395128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SYNTHESIS AND CHARACTERIZATION OF COORDINATION COMPOUNDS OF 3d-METAL MALEATES WITH THIOSEMICARBAZIDE","authors":"T. Koksharova, T. Mandzii, A. Kovalyov, D. V. Kramarenko, T. Y. Brazhnik, O. Ivanenko","doi":"10.18524/2304-0947.2021.3(79).240752","DOIUrl":"https://doi.org/10.18524/2304-0947.2021.3(79).240752","url":null,"abstract":"Complexes of copper(II), nickel(II), cobalt(III), and zinc(II) maleates with thiosemicarbazide were synthesized. The resulting compounds were characterized by the elemental analysis data, infrared spectroscopy, diffuse reflectance spectroscopy, and thermogravimetry.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"36 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91468909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"WATER ROLE IN THE GASES CHEMOSORPORATION PROCESSES BY SORPTION-ACTIVE MATERIALS","authors":"A. Ennan, R. M. Dlubovskiy, R. Khoma","doi":"10.18524/2304-0947.2021.3(79).240717","DOIUrl":"https://doi.org/10.18524/2304-0947.2021.3(79).240717","url":null,"abstract":"The work summarizes the literature data on the hydration and chemisorption of toxic gases by polymeric sorption-active materials. The mechanisms of absorption by granular and fibrous ion-exchange and impregnated materials and the state of adsorbed water have been studied using various research methods (gravimetric, sorption-thermochemical, derivatographic, IR spectroscopic). The regularities of the hydration processes of granular strongly acidic sulfonic cationexchangers of the brands KU‑2 and KU‑23 (macroporous analogue), fibrous strongly acidic sulfonic cation- exchanger VION KS‑3, fibrous weakly acid carboxylic cation exchanger VION KN‑1 in various ionic forms are considered. Among the anion exchangers, the hydration of granular strongly basic anion- exchangers of the brand AV‑17, granular weakly basic anionexchangers of the brands AN‑25 (AN‑251 macroporous analogue) and ANKB‑35, fibrous strongly basic anion- exchangers of the brands FIBAN A‑6 and FIBAN A‑12, fibrous medium basic anion- exchangers of the brands CM‑2, fibrous weakly basic anion- exchangers of the brands CM-A1, VION AN‑1, VION AN‑3, FIBAN A‑5, FIBAN A‑11 and FIBAN AK‑22 are considered. It has been established that, by nature, the bond with the active centers of water is derided into a «bound» and a ordiner – «free». The first one is a monolayer and the nearest bonded with the ion of the ball; the other is the osmotic swelling water. It has been shown that for the effective absorption of most toxic gases and vapors (SO2, HCl, Cl2, SiF4, HF, NO2, NH3, аміни, COCl2, O3), it is necessary to have «free» water, which is not only a diffusion medium in which mass transfer proceeds, but also is a direct participant in chemisorption.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73396879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"LANTHANIDE COMPLEXES WITH REGIOISOMERS OF CHLORO-SUBSTITUTED TETRAPHENYLPORPHYRIN","authors":"N. Semenishyn","doi":"10.18524/2304-0947.2021.3(79).240750","DOIUrl":"https://doi.org/10.18524/2304-0947.2021.3(79).240750","url":null,"abstract":"Several isomeric complexes of Yb (III) and Lu(III) with H2tpp and its tetrachloro-substituted derivatives were synthesized. Symmetrical ortho-, meta- and para-positioning of four heavy atoms allows to study their effect on emission features of complexes. Obtained results show the rise of 4f-luminescence effectiveness in the row ortho-meta-para isomers.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"127 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74689037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"MIXED-LIGAND HETEROMETALLIC COMPLEXES OF Ge(IV)-M2+ (Mn, Fe, Co, Ni, Zn) WITH 1,3-DIAMINO-2-HYDROXYPROPANE N,N,N',N'-TETRAACETIC ACID","authors":"E. Chebanenko, I. Seifullina, E. Martsinko","doi":"10.18524/2304-0947.2021.3(79).240751","DOIUrl":"https://doi.org/10.18524/2304-0947.2021.3(79).240751","url":null,"abstract":"There have been developed a novel synthetic method that allowed to obtain raw of mixed-ligand heterometallic binuclear complexes of Ge(IV)-M2+ (Mn, Fe, Co, Ni, Zn) with 1,3-diamino‑2-hydroxypropane N, N, N’, N’-tetraacetic acid (H5hpdta). Compounds have been characterized by the set of methods: elemental analysis, thermogravimetry, IR‑spectroscopy, spectrum of diffuse reflection, magnetic suspensibility. According to the elemental analysis, the molar ratio Ge: M: H5hpdta: bipy= 1:1:1:1 in the obtained compounds 1‑5 corresponds to the formula [(H2O)(OH)Ge(m-hpdta)M(bipy)]·nН2О (M=Mn n=3 (1), Fe n=2 (2), Co n=4 (3), Ni n=4 (4), Zn n=3 (5). Complexes have yellow (1), red (2), orange (3), violet (4) and pink (5) colors and are stable on air. Compounds 1‑5 exist in the form of crystal hydrates, that contain certain amount of water molecules, that are eliminated into the gas phase while heating in the wide range of temperatures (t=80‑250 °C), which is accompanied with the low-temperature endothermic effect. This indicates the presence of a system of stable hydrogen bonds in their crystal structure. Analysis of the IR‑spectra 1‑5 revealed that form and coordination of ligands is similar. Deprotonation of all carboxylic groups in the ligands (H5hpdta) and their bonding to germanium and d-metal is confirmed with the absence in the IR‑spectra 1‑5 absorption bands characteristic for the free СООН H5hpdta (1716 сm‑1) and nas(СОО-) і ns(СОО-) bands. Disappearance of the ν(С-OН)-1210 сm‑1 and appearance of the ν(С-O)alk., νas(Ge-O-M), νs(Ge-O- M) absorption band indicates that OH‑group of H5hpdta is deprotonated and performs bridging function. 2,2`-bipyridine bidentatly coordinates to the d-metal, binds to the O, N‑atoms of hpdta5- ligand and reaches coordination number 6. The last ligand plays the bringing role between Ge-dmetal, shows itself as ditopic, octadentate in total. According to the magnetic moments of 3, 4 and their diffuse reflection spectra, polyhedrons of Co (II), Ni (II) are octahedrons, which are realized due to the bidentate coordination of bipyridine and four bonds with nitrogen and oxygen of hpdta5-. Structure of heterometallic binuclear complexes 1‑5 is similar. Ligand hpdta5- shows itself as octadentate ditopic, all carboxylate groups monodentatly coordinate to metals, oxygen atom of the deprotonated OH‑group performs the bridging function.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90995288","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"REDOX PROCESSES IN THE REACTIONS OF N-ARYLSULFONYL-1,4-NAPHTНOQUINONЕIMINES WITH CERTAIN NUCLEOPHILES","authors":"A. Avdeenko, Yu. P. Kholmovoi, A. L. Yusina","doi":"10.18524/2304-0947.2021.3(79).240753","DOIUrl":"https://doi.org/10.18524/2304-0947.2021.3(79).240753","url":null,"abstract":"Quinone-hydroquinone pairs are prototypes of organic redox systems, and studies of the electrochemical behavior of these compounds are of great interest for research. Electrochemical behavior associated with the equilibrium of electron-proton transfer provides information about the molecular structure and environment of the process. Apart from chemical aspects, quinones play an important role in the biochemistry of living cells. Quinone derivatives, used as drugs for several types of human cancers, have been found to have their biological activity related to their redox behavior. Quinoneimines-aminophenols form similar pairs. In nucleophilic addition reactions of N‑substituted p-quinoneimines, parallel redox processes are often observed, and the higher the redox potential of quinoneimine, the greater the likelihood of such processes. Naphthoquinoneimines with aromatic amines and acylhydrazines follow the scheme of 1,4-addition, but as reaction products are oxidized products -4-arylsulfonylamido‑2-arylamino(2-aroylamino)-1,4-naphthoquinoneimines. The oxidant may be the original naphthoquinoneimine and oxygen. Studies have shown that oxygen in the reaction of 1,4-naphthoquinoneimines with acylhydrazines is the only oxidant that oxidizes the product of 1,4-addition, as evidenced by the study of redox potentials. Both oxidized and reduced form of the compounds, as naphthoquinoneimine and the corresponding aminonaphthol, are used to determine the redox potential by direct potentiometry. Due to the instability of the reduced form in the case of the pair naphthoquinoneimine-aminonaphthol, we used only the reduced form, which is oxidized in the cell by oxygen. The redox potential of the naphthoquinoneimine-aminonaphthol galvanic pair was determined as the average value between the potential Emax, which was established in the system upon complete oxidation of the starting substance, that is, when only naphthoquinone imine remains in the system, and the potential Emin, which was registered at the beginning of the process in the system with the reduced form – the corresponding aminonaphthol. This is the method of direct potentiometry in the variant of the middle potential.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"23 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84843337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SORPTION OF ERYTHROSINE ONTO SILICA GEL MODIFIED BY CETYLPYRIDINIUM BROMIDE","authors":"O. Guzenko, O. Zhukovetska, D. M. Mukienko, V. V. Shopovalenko, A. Chebotarev, D. Snigur","doi":"10.18524/2304-0947.2021.3(79).240755","DOIUrl":"https://doi.org/10.18524/2304-0947.2021.3(79).240755","url":null,"abstract":"In the current paper, adsorbent based on silica gel L 40/100 modified with cetylpyridinium bromide was obtained. The presence of cetylpyridinium cations on the silica gel surface was confirmed by the diffuse reflectance infrared fourier transform spectroscopy method. The sorption conditions of erythrosine from dilute aqueous solutions with the proposed sorbent were studied and optimized. It is shown that the use of modified silica gel allows efficient (>95%) extraction of erythrosine from aqueous solutions. Under optimal sorption conditions (pH 7, sorbent dosage 0.1 g and sorption time is 15 min), the sorption capacity of modified erythrosine sorbents was determined. It is shown that, with increasing temperature, a change in the isotherm type from the H‑type to the L‑type is observed. This change can be explained by the aggregation of erythrosin in solution, which is a competitive sorption process. It was shown that adsorption isotherms were well described by the Langmuir equation. Thermodynamic studies have made it possible to establish the spontaneous sorption. The desorption of erythrosine from the surface of silica gel modified with cetylpyridinium bromide was studied. It is shown that when using solutions of sulfuric acid, sodium hydroxide and distilled water, desorption does not occur. It was shown that the most effective eluent is solution of sodium dodecylsulfate in alkaline medium, and desorption of erythrosine occurs due to the destruction of ion pairs of dye anions with cetylpyridinium cations fixed on the surface. The data obtained can then be used to develop a test system for determination of erythrosine via corresponding colorimetric scales or for quantitative solid phase extraction and adsorption-spectroscopic quantification of erythrosine in some real samples.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75316649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"NEW ACID-BASIC INDICATORS: RESEARCH USING A SMARTPHONE","authors":"A. Avdeenko, Yu.P. Holmovoj, S. Konovalova, I. Yakymenko","doi":"10.18524/2304-0947.2021.1(77).226144","DOIUrl":"https://doi.org/10.18524/2304-0947.2021.1(77).226144","url":null,"abstract":"Modern cameras, desktop scanners, smartphones allow not only registering an image, but also determining its color characteristics. That allows us to quickly, objectively and automatically determine the color characteristics of colored samples in acid-base titration, because there is a significant error at visually determining the pH range of the color transition. In analytical chemistry the characteristics of acid-base indicators are very important, in particular their pH transition interval. But the disadvantage of most indicators is the wide range of color transition: from 1 to 3 pH units. The aim of this work is to find new acid-base indicators that change color in an alkaline environment and have a narrow pH range of the color transition. We have developed the apparatus and technique of convenient and highprecision simultaneous determination of the pH of the medium and the color of the acidbase indicators. In acid-base titration the PH measurements were performed with a combined glass electrode AD1131 by рН-meter AD1000. The color transition was determined with help of a smartphone with the subsequent processing of the results by computer software. The color characteristics were measured for each channel of the RGB model in the range from 0 to 255. Our apparatus is small and mobile, and allows us simultaneously to measure the pH of the medium and accurately to determine the color characteristics. As a result, we can construct graphical dependencies of color on pH for each channel of the RGB model. We found the N-arylsulfonyl-2-aroylamido-1,4-benzo(naphto)quinone monoimines and 2,5-dibenzoylamido-1,4-benzoquinone are good acid-base indicators. They “work” in the pH range from 8.82 to 11.35 and have a very narrow color transition interval from 0.10 to 0.61. Solutions of these compounds in an alkaline medium have bright intense colors due to formation of mesomeric ions. That allows using of these indicators in the titration of weak acids with strong bases and vice versa by the method of neutralization.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"23 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90592336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"POTENTIOMETRIC STUDY OF KINETICS AND MECHANISM FORMATION OF SILVER NANOPARTICLES STABILIZED BY SYNTHETIC FULVATES","authors":"V. Litvin, Ю. С. Сметенко, І. О. Озівська","doi":"10.18524/2304-0947.2021.3(79).240754","DOIUrl":"https://doi.org/10.18524/2304-0947.2021.3(79).240754","url":null,"abstract":"Silver nanoparticles are actively studied due to their unique properties and wide use in various fields. In this study, silver nanoparticles were obtained by reacting Ag+ ions with synthetic fulvic acids derived from quercetin. Synthetic fulvic acids perform a dual function: a reducer of silver ions and a stabilizer of the formed nanoparticles The presence of silver nanoparticles in the solution is confirmed by the presence of a maximum in the absorption spectrum at 400 nm, which is due to the phenomenon of surface plasmon resonance. The parameters of the crystal lattice were established using the X‑ray diffraction method. The average nanoparticle size calculated by the Scherrer formula is 28 nm. The kinetics and mechanism formation of silver nanoparticles were studied by potentiometry, which allows direct and continuous control of the consumption of silver ions in the synthesis process. It is established that the mechanism of the process depends on the pH of the medium. In particular, at high pH values of the reaction medium there is a heterogeneous mechanism, while at low – homogeneous. The heterogeneous mechanism of formation of silver nanoparticles is characterized by the presence of three stages, in particular: 1) formation of Ag2O microparticles after mixing reagents, 2) reduction of Ag+ ions by synthetic fulvic acids from quercetin on the surface of formed Ag2O microparticles, which are heterogeneous nucleation centers. 3) reduction of Ag+ ions from solution on the surface of silver nanoparticles after complete dissolution of Ag2O microparticles (this process is described by first-order kinetics by Ag+). Activation parameters for different stages of silver nanoparticle formation using quercetin fulvic acids were calculated. A potentiometric study of the influence of the degree of aeration of the medium on the kinetics of changes in the pAg system was performed.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"68 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83261281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ALTERNATIVE METHODS OF SYNTHESIS OF NOVEL HETEROSYNTHONES – FUNCTIONALIZED HYPOXANTHINE PYRIMIDINES","authors":"V. Povstyanoy, T. A. Yuyrova, A. N. Retchitskiy, A. A. Krysko","doi":"10.18524/2304-0947.2021.2(78).233823","DOIUrl":"https://doi.org/10.18524/2304-0947.2021.2(78).233823","url":null,"abstract":"It has been known that derivatives of dihydropyrimidine and xanthine possess the physiological activity of the wide spectrum of action. The combination of the specified heterocyclic fragments within one molecule can lead to the increase of its known types of biological activity as well as to the discovery of novel types of activity. We have previously reported the synthesis of intermediates, which consist of functionalized dihydropyrimidines, connected via a methylene bridge with the halogen substituted derivatives of the ophylline, 3-methylxanthine and imidazole. It was also observed that these compounds would react with N‑nucleophiles with the formation of various branched and cyclic products. The aim of this work was to determine the optimal conditions for obtaining heterocyclic products as a result of conjugation of bromomethyldihydropyrimidine and hypoxanthine at the positions C6 and C1 via a methylene bridge. It is important to note, that the latter can be widely modified by using structurally diverse aromatic aldehydes during the synthesis of dihydropyrimidine core by using Biginelli reaction, which explains structural diversity of the reaction products. After having tried various reaction conditions, we have concluded that the optimal method for obtaining the products entailed keeping equimolar ratios of bromomethyl substituted dihydropyrimidines and 1-potassium‑2-chloro‑7-methylhypoxanthine in dry ethanol for 4 hours. The ester group at the C5 of dihydropyrimidine ring and a chlorine leaving group at C2 of hypoxanthine fragments of the molecule allow to consider these structures as pro missing synthons for farther synthesis of condensed pyrimidine and xanthine systems. The structures of novel compounds have been confirmed with the methods such as HPLC/MS, 1H, and 13C NMR spectroscopy.","PeriodicalId":19451,"journal":{"name":"Odesa National University Herald. Chemistry","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89035803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}