Journal of Organic and Pharmaceutical Chemistry 2021-03-29T17:46:59+00:00 Dmitry Alexandrovich Lega Open Journal Systems «Journal of Organic and Pharmaceutical Chemistry» was begun to publish in 2003 and is regarded as assignee of «Fìzìologìčno aktivnì rečovini» journal that was founded in 1966. The journal was established by National Academy of Sciences (NAS) of Ukraine in cooperation with Institute of Organic chemistry of NAS of Ukraine and National University of Pharmacy (state registration certificate КВ №23086-12926ПР, 05.01.2018, ISSN 2308-8303 (Print); ISSN 2518-1548 (Online)). The journal is included in the List of specialized scientific editions of Ukraine for publishing results of PhD works in the fields of chemistry and pharmacy approved by the Ministry of Education and Science of Ukraine (decree of the Ministry of Education and Science of Ukraine №1643, 28.12.2019, category "B"). The preparative synthetic approach to 4-(trifluoromethoxy)piperidine and 4-(trifluoromethoxymethyl)piperidine 2021-01-27T00:04:36+00:00 Ivan G. Logvinenko Violetta G. Dolovanyuk Ivan S. Kondratov <p><strong> <span class="fontstyle0">Aim. </span></strong><span class="fontstyle2">To develop a convenient synthetic approach for the preparation of multigram amounts of 4-(trifluoromethoxy)-piperidine and 4-(trifluoromethoxymethyl)piperidine – promising building blocks for medicinal chemistry.<br /></span><strong><span class="fontstyle0">Results and discussion. </span></strong><span class="fontstyle2">4-(Trifluoromethoxy)piperidine (8.4 g) and 4-(trifluoromethoxymethyl)piperidine (12.9 g) were synthesized in 5 stages starting from 4-hydroxypiperidine (the overall yield 40 %) and 4-(hydroxymethyl)piperidine (the overall yield 13.5 %), respectively.<br /></span><strong><span class="fontstyle0">Experimental part. </span></strong><span class="fontstyle2">The first stage of the synthetic strategy was acylation of 4-hydroxypiperidine with benzoyl chloride. N-benzoyl-4-hydroxypiperidine obtained was transformed to N-benzoyl-4-(trifluoromethoxy)piperidine in two stages using the Hiyama method (the synthesis of the corresponding S-methyl xanthate with the subsequent desulfurization/fluorination using N-bromosuccinimide and Olah’s reagent). Then the N-benzoyl group was reduced to benzyl one, which was removed using 1-chloroethyl chloroformate. The similar approach was applied to the synthesis of 4-(trifluoromethoxymethyl)piperidine starting from 4-(hydroxymethyl)piperidine. The structure and composition of the compounds synthesized were confrmed by </span><sup><span class="fontstyle2">1</span></sup><span class="fontstyle2">Н, </span><sup><span class="fontstyle2">13</span></sup><span class="fontstyle2">C and </span><sup><span class="fontstyle2">19</span></sup><span class="fontstyle2">F NMR spectroscopy,<br />mass-spectrometry and elemental analysis.<br /></span><span class="fontstyle0"><strong>Conclusions.</strong> </span><span class="fontstyle2">The synthetic approach developed is a convenient method for the multigram preparation of<br />4-(trifluoromethoxy)piperidine and 4-(trifluoromethoxymethyl)piperidine and can be used for the synthesis of other secondary amines containing the CF</span><sub><span class="fontstyle2">3</span></sub><span class="fontstyle2">O-group.<br /></span><em><strong><span class="fontstyle3">Key words: </span></strong></em><span class="fontstyle2">fluorination; trifluoromethoxy group; xanthate; piperidine; protection group</span> </p> 2021-03-15T00:00:00+00:00 Copyright (c) 2021 National University of Pharmacy Convenient approaches to the synthesis of 6-amino- and 6-oxoimidazo[4,5-b]pyrazolo[3,4-e]pyridines 2021-03-18T19:02:44+00:00 G. G. Yakovenko M. V. Vovk <p><strong> <span class="fontstyle0">Aim. </span></strong><span class="fontstyle2">To develop convenient approaches to the synthesis of 6-amino- and 6-oxoimidazo[4,5-</span><em><span class="fontstyle3">b</span></em><span class="fontstyle2">]pyrazolo[3,4-</span><em><span class="fontstyle3">e</span></em><span class="fontstyle2">]pyridines as promising biologically active scaffolds.<br /></span><strong><span class="fontstyle0">Results and discussion. </span></strong><span class="fontstyle2">It has been found that cyclocondensation of N-Boc-4-aminopyrazole-5-carbaldehydes with creatinine can be used as an effective method for obtaining 6-aminoimidazo[4,5-</span><em><span class="fontstyle3">b</span></em><span class="fontstyle2">]pyrazolo[3,4-</span><em><span class="fontstyle3">e</span></em><span class="fontstyle2">]pyridines previously unknown. For the synthesis of their 6-oxoanalogs, the reaction of 5-aminopyrazolo[4,3-</span><em><span class="fontstyle3">b</span></em><span class="fontstyle2">]pyridine-6-carboxylic acids used in a modifed Curtius rearrangement with diphenylphosphorylazide was successful. This method was implemented through the stage of the intermediate aminoisocyanates formation.<br /></span><strong><span class="fontstyle0">Experimental part. </span></strong><span class="fontstyle2">The reaction of N-Boc-4-aminopyrazole-5-carbaldehydes with creatinine in the presence of pyrrolidine as a catalyst in refluxing acetic acid allowed to obtain 6-aminoimidazo[4,5-</span><em><span class="fontstyle3">b</span></em><span class="fontstyle2">]pirazolo[3,4-</span><em><span class="fontstyle3">e</span></em><span class="fontstyle2">]pyridines with the yields of 54 – 70 %. The structure of the compounds synthesized was proven by spectral measurements. In the </span><sup><span class="fontstyle2">1</span></sup><span class="fontstyle2">H NMR spectra there were singlets of H-3 (7.63 – 7.88 ppm) and H-8 (7.87 – 8.26 ppm) protons, as well as broad singlets of the NH</span><sub><span class="fontstyle2">2 </span></sub><span class="fontstyle2">group in the range of 7.05 – 7.21 ppm. Heating of 5-aminopyrazolo[4,3-</span><em><span class="fontstyle3">b</span></em><span class="fontstyle2">]pyridine-6-carboxylic acids with triethylamine and diphenylphosphorylazide in dioxane for 6 hours gave 1-substituted imidazo[4,5-</span><em><span class="fontstyle3">b</span></em><span class="fontstyle2">]pyrazolo[3,4-</span><em><span class="fontstyle3">е</span></em><span class="fontstyle2">]pyridine-6(5</span><em><span class="fontstyle3">Н</span></em><span class="fontstyle2">)-ones with the yields of 67 – 80 %. The IR-spectra of the compounds synthesized were characterized by the absorption bands of the C=O (1705 – 1708 cm</span><sup><span class="fontstyle2">-1</span></sup><span class="fontstyle2">) and NH (3275 – 3281 cm</span><sup><span class="fontstyle2">-1</span></sup><span class="fontstyle2">) groups. </span><sup><span class="fontstyle2">1</span></sup><span class="fontstyle2">H NMR-spectra were characterized by singlets of H-3 and H-8 protons in the intervals of 7.43 – 8.08 ppm and 7.92 – 8.32 ppm respectively, as well as by two broad singlets of NH-protons in the ranges of 10.90 – 11.12 ppm and 11.25 – 11.37 ppm.<br /></span><strong><span class="fontstyle0">Conclusions</span></strong><span class="fontstyle2"><strong>.</strong> Effective approaches to the synthesis of new promising heterocyclic systems of 6-amino- and<br />6-oxoimidazo[4,5-</span><em><span class="fontstyle3">b</span></em><span class="fontstyle2">]pirazolo[3,4-</span><em><span class="fontstyle3">e</span></em><span class="fontstyle2">]pyridines have been developed. Cyclocondensations of N-Boc-4-aminopyrazole-5-carbaldehydes with creatinine and 5-aminopyrazolo[4,3-</span><em><span class="fontstyle3">b</span></em><span class="fontstyle2">]pyridine-6-carboxylic acids with diphenylphosphorylazide have been proven to be convenient ways to obtain these compounds with good yields.<br /></span><em><strong><span class="fontstyle4">Key words</span><span class="fontstyle0">: </span></strong></em><span class="fontstyle2">N-Boc-4-aminopyrazole-5-carbaldehyde; creatinine; 5-aminopyrazolo[4,3-</span><em><span class="fontstyle3">b</span></em><span class="fontstyle2">]pyridine-<br />6-carboxylic acid; diphenylphosphorylazide; 6-amino(oxo)imidazo[4,5-</span><em><span class="fontstyle3">b</span></em><span class="fontstyle2">]pyrazolo[3,4-</span><em><span class="fontstyle3">e</span></em><span class="fontstyle2">]pyridines;<br />cyclocondensation</span> </p> 2021-03-15T00:00:00+00:00 Copyright (c) 2021 National University of Pharmacy The determination of the phytochemical composition of the Altabor substance 2020-05-05T04:31:18+00:00 S. Yu. Sheiko A. S. Shalamay <p><span class="fontstyle0">The development of medicines based on alder cone extracts led to the introduction of Altan and Altabor<br />medicines into medical practice. The technology of extraction cake from cones has made it possible to obtain extracts with different therapeutic properties.<br /></span><span class="fontstyle2"><strong>Aim.</strong> </span><span class="fontstyle0">To develop an effective method for studying the qualitative composition of the Altabor substance and<br />determine the quantitative content of its components.<br /></span><span class="fontstyle2"><strong>Results and discussion.</strong> </span><span class="fontstyle0">The Altabor substance is a complex mixture of ellagitannins containing more than 70 components. The main components of the extract (or their isomers) were determined by mass spectrometry and by comparing the retention times with the literature data. Gallic, ellagic, valoneic acids dilactone were conclusively determined by adding reference standards of these acids to the extract. The substance contains the following compounds: 2,3-hexahydroxydiphenoyl-(α/β)-glucose t</span><span class="fontstyle0"><sub>r1 </sub></span><span class="fontstyle0">= 0.55 min, t</span><span class="fontstyle0"><sub>r2 </sub></span><span class="fontstyle0">= 0.89 min (α and β isomers), 4,6-O-[(S)-valeonyl]-D-glucose (isomer) t</span><sub><span class="fontstyle0">r </span></sub><span class="fontstyle0">= 0.64 min, gallic acid t</span><sub><span class="fontstyle0">r </span></sub><span class="fontstyle0">= 1.198 min, pedunculagin t</span><sub><span class="fontstyle0">r1 </span></sub><span class="fontstyle0">= 3.63 min, t</span><sub><span class="fontstyle0">r2 </span></sub><span class="fontstyle0">= 4.62 min<br />(α and β isomers), proecoxin A (isomer) t</span><sub><span class="fontstyle0">r </span></sub><span class="fontstyle0">= 4.78 min, valoneic acid dilactone t</span><sub><span class="fontstyle0">r </span></sub><span class="fontstyle0">= 6.19 min, ellagic acid pentoside (isomer) t</span><sub><span class="fontstyle0">r </span></sub><span class="fontstyle0">= 7.07 min, ellagic acid t</span><sub><span class="fontstyle0">r </span></sub><span class="fontstyle0">= 7.335 min.<br /></span><strong><span class="fontstyle2">Experimental part. </span></strong><span class="fontstyle0">The composition analysis was performed using an Agilent 1200 chromatograph with a UV detector, a G6140 mass detector, an Alltech 3300 light scattering detector (ELSD), as well as the Agilent ChemStation Rev.B.04.03 software. The molecular weights of the compounds in the extract were determined using the method of mass spectrometry of ESI-electrospray ionization. The determination of the components was performed using an ultraviolet detector at a wavelength of 280 nm. The column was Rapid Resolution HT Cartige, 4.6 × 30 mm, 1.8 μm, Zorbax SB-C18.<br /></span><strong><span class="fontstyle2">Conclusions. </span></strong><span class="fontstyle0">A new effective method of analysis of the Altabor substance has been developed; it allows<br />determining the qualitative and quantitative content of its structural components. The method gives the possibility to control the process of obtaining the Altabor substance, study the dependence of its composition on the conditions of its obtaining, batch number, place, time of the natural raw material collection, and study the composition of other pharmaceutical substances, the plant raw material containing tannins. The advantage of the method is<br />the short time (up to 10 min) of analysis using high-performance liquid chromatography at high resolution.<br /></span><em><span class="fontstyle3"><strong>Key words:</strong> </span></em><span class="fontstyle0">gallotannins; ellagitannins; Altabor; chemical composition; structure; HPLC (high-performance liquid chromatography)</span> </p> 2021-03-15T00:00:00+00:00 Copyright (c) 2021 National University of Pharmacy A novel luminol-based chemiluminescence method for detecting acetylcholine 2021-03-08T19:44:15+00:00 M. Ye. Blazheyevskіy O. V. Koval’ska K. V. Dynnyk <p><span class="fontstyle0"><strong>Aim.</strong> </span><span class="fontstyle2">To develop а new simple non-enzymatic method for the determination of acetylcholine (ACh) by the chemiluminescent reaction of luminol under conditions of the enzymatic hydrolysis of acetylcholine (pH 8.5).<br /></span><span class="fontstyle0"><strong>Experimental part.</strong> </span><span class="fontstyle2">The method proposed is based on the perhydrolysis reaction of ACh by the excess of<br />hydrogen peroxide with the formation of peracetic acid. The latter was further determined by the activation effect of the luminol chemiluminescent oxidation reaction in the presence of hydrogen peroxide. The analytical signal was the summary luminescence (Σ) registered within certain time.<br /></span><span class="fontstyle0"><strong>Results and discussion.</strong> </span><span class="fontstyle2">The pH range of the analytically applicable system was from 8.2 to 8.5. The effect of ACh + H</span><sub><span class="fontstyle2">2</span></sub><span class="fontstyle2">O</span><sub><span class="fontstyle2">2 </span></sub><span class="fontstyle2">incubation period on the reaction progress was also studied. The increase of the incubation period enhanced the sensitivity of the method (the limit of detection (LOD)), but because of practical reasons (especially the detection speed) and practical experience the incubation period was set to 30 min. The linear dependence was observed in the acetylcholine chloride concentration range of (0.8 – 2.8) </span><span class="fontstyle3">× </span><span class="fontstyle2">10</span><sup><span class="fontstyle2">-4 </span></sup><span class="fontstyle2">mol/L. While determining acetylcholine chloride in the concentration range of (1.1 – 2.2) × 10</span><sup><span class="fontstyle2">-4 </span></sup><span class="fontstyle2">mol/L the relative standard deviation (RSD) did not<br />exceed 3 % ((</span><span class="fontstyle4">X </span><span class="fontstyle2">– </span><span class="fontstyle4">μ</span><span class="fontstyle2">) × 100 %/μ = –0.5…+0.5 %). The Limit of Quantitation (LOQ, 10S) was 7.7 × 10</span><span class="fontstyle2">-5 </span><span class="fontstyle2">mol/L.<br /></span><strong><span class="fontstyle0">Conclusions</span></strong><span class="fontstyle2"><strong>.</strong> A new non-enzymatic kinetic method for the chemiluminescent determination of ACh in aqueous solutions and the pharmaceutical formulation Acetylcholinchlorid Injeel</span><span class="fontstyle2">® </span><span class="fontstyle2">has been proposed. This method is simple, fast, inexpensive, and thus appropriate for the routine ACh quality control in the laboratories of hospitals, pharmaceutical industries and research institutions.<br /></span><em><strong><span class="fontstyle5">Key words: </span></strong></em><span class="fontstyle2">acetylcholine; chemiluminescence method</span> </p> 2021-03-15T00:00:00+00:00 Copyright (c) 2021 National University of Pharmacy Development of methods for standardization of Crocus sativus (saffron) stigmas for inclusion in the draft monograph of the State Pharmacopoeia of Ukraine 2020-11-08T19:34:13+00:00 O. O. Mykhailenko A. G. Kotov E. E. Kotova L. M. Sira V. M. Kovalyov V. A. Georgiants <p><span class="fontstyle0">Crocus sativus L. from the Iridaceae family is a medicinal and edible plant that has recently been actively cultivated in Ukraine. Saffron spice is crocus flower stigmas exhibiting a wide range of the pharmacological activity due to its three main bioactive compounds: crocin, picrocrocin and safranal. The quality of this raw material is regulated<br />by various normative documents, but there is no monograph in the State Pharmacopoeia of Ukraine (SPhU).</span></p> <p><strong> <span class="fontstyle0">Aim</span></strong><span class="fontstyle1"><strong>.</strong> To perform a comparative analysis of the monograph “Saffron for homoeopatic preparations” from the Ph. Eur. 9.0, “Saffron. Croci stigma” from the Deutscher arzneimittel codex (DAC) and “Spices – Saffron (</span><span class="fontstyle3">Crocus sativus </span><span class="fontstyle1">L.)” from the ISO 3632 by the following indicators: description, identifcation (microscopy and TLC), impurities, loss on drying, total ash and quantifcation of crocin, picrocrocin and safranal by UV-Vis-spectrophotometry to clarify the possibility of harmonizing the requirements of the national legal framework for </span><span class="fontstyle3">Crocus </span><span class="fontstyle1">stigmas with<br />the Ph. Eur. 9.0, DAC and ISO 3632. The results of the analysis will be taken into account in the development of the monograph of the national part of the SPhU “</span><span class="fontstyle3">Crocus </span><span class="fontstyle1">stigmas (saffron)”.<br /></span><span class="fontstyle0"><strong>Results and discussion.</strong> </span><span class="fontstyle1">The quality indicators of </span><span class="fontstyle3">Crocus </span><span class="fontstyle1">stigmas and their standardization determined<br />by the monograph in the Ph. Eur. 9.0, DAC and ISO 3632 on the raw material studied have been analyzed; some differences in the regulated quality indicators of the raw material have been found. The results of our own research have shown that the samples of the Ukrainian </span><span class="fontstyle3">Crocus </span><span class="fontstyle1">(saffron) meet all these requirements. The results of the macro- and microscopic examination of the raw material are given. The chromatographic examination has<br />been performed in accordance with the Ph. Eur. 9.0 and DAC using crocin as a standard compound; the quantitative determination of crocin, picrocrocin and safranal in 8 samples of </span><span class="fontstyle3">Crocus </span><span class="fontstyle1">stigmas has been performed by UV-Vis-spectrophotometry in accordance with the ISO 3632. It has been proposed to introduce the following indicators to determine the specifc absorption rate: for crocin (C</span><sub><span class="fontstyle1">44</span></sub><span class="fontstyle1">H</span><sub><span class="fontstyle1">64</span></sub><span class="fontstyle1">O</span><sub><span class="fontstyle1">24</span></sub><span class="fontstyle1">; Mw – 976.70) not less than 180, for safranal (C</span><sub><span class="fontstyle1">10</span></sub><span class="fontstyle1">H</span><sub><span class="fontstyle1">14</span></sub><span class="fontstyle1">O; Mw – 150.22) – not less than 30, for picrocrocin (C</span><sub><span class="fontstyle1">16</span></sub><span class="fontstyle1">H</span><sub><span class="fontstyle1">26</span></sub><span class="fontstyle1">O</span><sub><span class="fontstyle1">7</span></sub><span class="fontstyle1">; Mw – 330.37) – not less than 60 calculated with reference to the dried raw material.<br /></span><span class="fontstyle0"><strong>Experimental part.</strong> </span><span class="fontstyle1">For analysis the dried stigmas of </span><span class="fontstyle3">Crocus sativus </span><span class="fontstyle1">(saffron) collected in the village<br />Lyubimivka, Kherson region, Ukraine (2016-2018), as well as commercial samples of saffron from Morocco,<br />Azerbaijan, Spain were used. The analysis of the leading normative documents containing monographs “</span><span class="fontstyle3">Crocus </span><span class="fontstyle1">stigmas”, among them the Eur. Ph. 9.0, DAC and ISO 3632, was performed. The studies included description of the appearance of the whole </span><span class="fontstyle3">Crocus </span><span class="fontstyle1">stigmas; loss on drying and the mass fraction of volatile compounds (105 °C, 16 h); the mass fraction of total ash. The amount of picrocrocin, safranal and crocin was measured by direct reading of the absorption of 1 % aqueous solution of stigmas at 257 nm, 330 nm and 440 nm, respectively, using<br />a UV-Vis-spectrophotometer.<br /></span><strong><span class="fontstyle0">Conclusions</span></strong><span class="fontstyle1"><strong>.</strong> The analysis of the requirements to quality of the medicinal raw material – stigmas of </span><span class="fontstyle3">Crocus sativus </span><span class="fontstyle1">– has been performed based on the monographs: “Saffron for homoeopatic preparations” from the Ph. Eur. 9.0, “Saffron. Croci stigma” from the Deutscher arzneimittel codex and “Spices – Saffron (</span><span class="fontstyle3">Crocus sativus </span><span class="fontstyle1">L.)” from the ISO 3632. The main criteria for standardization of the raw material have been determined. It has been proposed to introduce the monograph to the national part of the SPhU “</span><span class="fontstyle3">Crocus </span><span class="fontstyle1">stigmas (saffron)” according to the following requirements: identifcation (macro- and microscopic signs; thin-layer chromatography (crocin); the quantitative<br />determination (the content of crocin, picrocrocin and safranal) adapted to the ISO 3632, performed by UV-Vis-spectrophotometry; impurities; loss on drying; total ash.<br /></span><em><strong><span class="fontstyle4">Key words: </span></strong></em><span class="fontstyle1">standardization; State Pharmacopoeia of Ukraine; </span><span class="fontstyle3">Crocus sativus </span><span class="fontstyle1">stigma; saffron; crocin</span> </p> 2021-03-15T00:00:00+00:00 Copyright (c) 2021 National University of Pharmacy The study of polyphenolic compounds of Pimpinella anisum herb and determination of their antioxidant activity 2021-03-08T19:40:06+00:00 U. Umarov S. V. Kolisnyk O. V. Kolisnyk M. Fatkhullaeva N. K. Chinibekova M. M. Khamdamov <p><span class="fontstyle1"><strong><span class="fontstyle0">Aim. </span></strong><span class="fontstyle2">To study the qualitative composition and quantitative content of the polyphenolic compounds in </span><span class="fontstyle3"><em>Pimpinella anisum</em> </span><span class="fontstyle2">herb and determine their antioxidant activity.<br /></span><span class="fontstyle0"><strong>Results and discussion.</strong> </span><span class="fontstyle2">Among the polyphenolic compounds contained in anise herb, chlorogenic acid<br />(4.409 mg/g) predominates. Signifcant amounts of catechins (3.104 mg/g), apigenin derivatives (3.077 mg/g) and luteolin (1.864 mg/g) also accumulate in the herb. Minor amounts of myricetin (0.105 mg/g) and naringenin (0.019 mg/g) derivatives, rutin (0.189 mg/g), quercetin (0.028 mg/g), apigenin (0.009 mg/g) and hesperetin (0.002 mg/g) are present. According to the research results, the antioxidant activity of polyphenolic compounds of anise herb with reference to ascorbic acid was found to be 67.76 ± 0.05 mmol/g. Rutin exhibited the antioxidant activity at the level of 3979.59 ± 0.08 mmol/g.<br /></span><span class="fontstyle0"><strong>Experimental part.</strong> </span><span class="fontstyle3"><em>Pimpinella anisum</em> </span><span class="fontstyle2">herb collected during the flowering stage in the summer of 2019 in<br />the Kharkiv region (Ukraine) was used for analysis. The analysis of 70 % ethanolic extract from anise herb was performed by high performance liquid chromatography using a Prominence LC-20 Shimadzu chromatographic system (Japan) with a SPD-20AV spectrophotometric detector, an Agilent Technologies Microsorb-MV-150 column (reversedphase, C18 modifed silica gel, length – 150 mm, diameter – 4.6 mm, particles size – 5 μm). Identifcation of substances in the extract was carried out by comparing the retention time and the spectral characteristics of the test substances with the same characteristics of the reference standards. The antioxidant activity was determined by the potentiometric method (pH meter – Hanna 2550, with redox electrode EZDO PO50) with reference to ascorbic acid.<br /></span><span class="fontstyle0"><strong>Conclusions.</strong> </span><span class="fontstyle2">The qualitative composition and quantitative content of polyphenolic compounds in the ethanolic extract of anise herb have been determined by high performance liquid chromatography. The total content of polyphenolic compounds is 17.576 mg/g. The antioxidant activity of polyphenolic compounds of anise herb with reference to ascorbic acid has been found to be 67.76 ± 0.05 mmol/g.<br /></span><em><span class="fontstyle4"><strong>Key words:</strong> </span></em><span class="fontstyle2">polyphenolic compounds; anise; herb; high performance liquid chromatography; antioxidant activity</span></span></p> 2021-03-15T00:00:00+00:00 Copyright (c) 2021 National University of Pharmacy The synthesis of 4-amino-5-(quinolin-2-yl)-4H-1,2,4-triazole-3-thiol and its interaction with aldehydes 2020-02-02T22:08:39+00:00 D. М. Zozulynets A. G. Kaplaushenko A. S. Korzhova <p><span class="fontstyle0"><strong>Aim.</strong> </span><span class="fontstyle2">To synthesize 4-amino-5-(quinolin-2-yl)-4</span><em><span class="fontstyle3">H</span></em><span class="fontstyle2">-1,2,4-triazole-3-thiol and study its reactivity in the reaction<br />with aldehydes.<br /></span><strong><span class="fontstyle0">Results and discussion. </span></strong><span class="fontstyle2">4-Amino-5-(quinolin-2-yl)-4</span><em><span class="fontstyle3">H</span></em><span class="fontstyle2">-1,2,4-triazole-3-thiol was synthesized, and a number of 4-(ethyl, aryl)idenamino derivatives were obtained on its basis.<br /></span><strong><span class="fontstyle0">Experimental part. </span></strong><span class="fontstyle2">Using a series of four successive reactions based on quinoline-2-carboxylic acid, 4-amino-5-(quinolin-2-yl)-4</span><em><span class="fontstyle3">H</span></em><span class="fontstyle2">-1,2,4-triazole-3-thiol was synthesized; its interaction with aldehydes allowed to obtain a number of 4-(ethyl, aryl)idenamino derivatives. The structure of all compounds synthesized was confrmed by IR and </span><sup><span class="fontstyle2">1</span></sup><span class="fontstyle2">H NMR spectroscopy, as well as by elemental analysis, and their purity by thin layer chromatography.<br /></span><strong><span class="fontstyle0">Conclusions. </span></strong><span class="fontstyle2">4-Amino-5-(quinolin-2-yl)-4</span><em><span class="fontstyle3">H</span></em><span class="fontstyle2">-1,2,4-triazole-3-thiol has been synthesized. It has been found that its interaction with aldehydes leads to the formation of new 4-((ethyl, aryl)idenamino)-5-(quinolin-2-yl)-4</span><em><span class="fontstyle3">H</span></em><span class="fontstyle2">-1,2,4-triazole-3-thiols.<br /></span><em><strong><span class="fontstyle4">Key words: </span></strong></em><span class="fontstyle2">5-(quinolin-2-yl)-1,2,4-triazole-3-thiol; 4-arylidenamino derivatives; quinaldic acid; biological<br />activity</span> </p> 2021-03-15T00:00:00+00:00 Copyright (c) 2021 National University of Pharmacy Validation of the alkalimetry method for the quantitative determination of free organic acids in raspberry leaves 2021-03-08T19:26:20+00:00 O. Yu. Maslov S. V. Kolisnyk T. A. Kostina Z. V. Shovkova E. Yu. Ahmedov M. A. Komisarenko <p> <span class="fontstyle0">Organic acids are a large group of biologically active compounds that perform important functions in the plant organism. Moreover, all plants, regardless of the species and family, contain organic acids to a small or large extent as organic acids belong to intermediate metabolites arising from the oxidation of proteins and amino acids, fats and carbohydrates.<br /></span><span class="fontstyle2"><strong>Aim.</strong> </span><span class="fontstyle0">To validate the method of alkalimetry proposed with potentiometric detection of the end-point for the quantitative determination of free organic acids in raspberry leaves.<br /></span><span class="fontstyle2"><strong>Results and discussion.</strong> </span><span class="fontstyle0">The method proposed was validated according to the International Conference on Harmonization (ICH) guidelines. The linearity was in the concentration range of 40 – 200 % (r</span><sup><span class="fontstyle0">2 </span></sup><span class="fontstyle0">= 0.9991). The percentage of recovery was found to be in the range of 98.77 – 102.48 %. The repeatability and intermediate precision were 1.58 % and 1.74 %, respectively. The method is accurate and reliable, with the relative standard deviation of less than 2 %.<br /></span><span class="fontstyle2"><strong>Experimental part.</strong> </span><span class="fontstyle0">Leaves of raspberry were collected in the Kharkiv region during the period of full ripening. A Hanna 2550 pH-meter with a HI 1131P potentiometric electrode was used for alkalimetric titration of free organic acids. The titration was carried out using a microburette with Class A accuracy.<br /></span><span class="fontstyle2"><strong>Conclusions.</strong> </span><span class="fontstyle0">The alkalimetry method for the quantitative determination of free organic acids in raspberry leaves has been proposed and validated according to the following parameters: specifcity, linearity, accuracy, repeatability, intermediate precision, robustness. It has been confrmed that the method is simple, reliable, accurate and cost-effective.<br /></span><em><span class="fontstyle3"><strong>Key words:</strong> </span></em><span class="fontstyle0">raspberry; leaves; free organic acids; alkalimetry; validation</span> </p> 2021-03-15T00:00:00+00:00 Copyright (c) 2021 National University of Pharmacy