French-Ukrainian Journal of Chemistry
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Spectrophotometric Assay of Prothipendyl through the Determination of Its Sulfoxide
Get PDFA new difference spectrophotometric method for the analysis of prothipendyl hydrochloride in commercial pharmaceutical preparations has been proposed. The method includes oxidation of an aliquot of the drug solution with potassium caroate to form the corresponding sulfoxide (ε278 = (13.69 ±0.01)×103 L mol/cm) and subsequent measurement of the optical density of the solution at 278 nm compared to that of the unoxidized drug solution of equal concentration. The graph of Beer's law for prothipendyl hydrochloride shows that the ΔA values measured at the corresponding wavelength are proportional to the concentration of the drug in the concentration range of 3.2-60 µg/mL. The characteristics of the curve calibration curve of the linear regression equation were as follows: ΔА = (0.0342±0.0006)C + (0.0501±0.025) (where C in μg/mL). The resulting difference in absorbance is independent of the presence of excipients and degradation products in the formulation. A new spectrophotometric technique has been developed and the possibility of quantitative determination of prothipendyl hydrochloride monohydrate in Dominal® tablets of 40 mg has been demonstrated. RSD =1.4% (δ= – 0.42%)
Chromones Modified with 7-Membered Heterocycles: Synthesis and Biological Activity
Get PDFThe present mini-review for the first time summarizes and systematizes all the data available in the literature on the synthesis and properties of сhromones modified with 7-membered heterocycles throughout the chemical space around the chromone framework. Most of the 2-, 6-, 7- and 8-hetarylsubstituted сhromones are represented in the patent literature and were obtained by nucleophilic substitution in the chromone core with a cyclic amine moiety. Methods for the synthesis of heterocyclic analogs of isoflavones are mainly based on 3-formylchromone, its derivatives, chromonylchalcones and by means of multicomponent reactions.
The biological activity of сhromones substituted with 7-membered heterocycles are also surveyed
Ultrasound Assisted Facile Synthesis of 2-Benzylidenebenzofuran-3(2H)-ones
Get PDF2-Benzylidenebenzofuran-3(2H)-ones commonly known as aurones, are an important class of oxygen heterocyclic compounds of flavonoid family. They exhibit some biological activities such as antioxidant, antifungal, anticancer, enzyme inhibitory, antiparasitic and antileishmanial activities. They are also responsible for imparting yellow color to the flowers and fruits. Owing to their varied importance, a simple and efficient method for the synthesis of 2-benzylidenebenzofuran-3(2H)-ones involving the reaction of 1-(2'-hydroxy-phenyl)-3-phenyl-propenones with copper acetate in ethanol under ultrasonic irradiation conditions has been described. The present method offers a faster reaction and a higher yield than conventional methods
Functionalized Derivatives of 2-azaspiro[3.3]heptane-1-carboxylic Acid and 7-oxa-2-azaspiro[3.5]nonane-1-carboxylic Acid for Drug Design
Get PDF2-azaspiro[3.3]heptane-1-carboxylic acid and 7-oxa-2-azaspiro[3.5]nonane-1-carboxylic acid, which had been reported as bioisoster of well-known pipecolic acid, were subjected to chemical transformations, resulting in a number of functionalized derivatives. The obtained molecules contained diversified functional groups, allowing their incorporation in bioactive compounds in versatile modes. Described synthetic approaches afforded multigram-scaled synthesis of the desired compounds with good yields, thus being applicable in drug desig
Dynamic Study and Modelling of Arsenic Removal from Groundwater Using Ferromagnetic Carbon as Fixed Bed Adsorbent in Column
Get PDFThis study investigated the performance of Ferromagnetic Carbon (FC) as an effective natural adsorbent for arsenic removal from groundwater in Dong Thap Province (Vietnam). To do this, leaching fixed-bed column experiments have been carried out. The influence of operating variables affecting the process was studied, under varying operating conditions and experimental data were modelled using bed depth service time (BDST) and mass transfer approaches. Speciation studies showed that the groundwater contained 48.5% of particulate arsenic and 51.5% of soluble arsenic. Indeed, As (III) and As (V) forms represented respectively 41.9% and 58.1% in the dissolved arsenic. As removal was parametric depending such as pH, flow rate, initial As and adsorbent mass, requiring an optimization for optimum conditions When the pH increased from 3 to 11, removal of As(V) decreased from 96.5% to 5% while As(III) removal increased from 40% to 69%. The increase of initial arsenic has caused an increase in removal efficiency of different forms of arsenic. The easy regeneration of FC using a molar sodium hydroxide solution suggests that is an efficient and low-cost material to reduce the contamination of arsenic in drinking groundwater
Quantitative Determination of Lincomycin in Dosage Forms by Iodometric Titration through Oxidation Reaction with Peroxomonosulfate
Get PDFThe kinetics of the oxidation reaction of Lincomycin hydrochloride (Link) with potassium hydrogen peroxomonosulfate (KHSO5) was studied depending on the pH of the medium. It has been established that the reaction kinetics obeys the general laws of specific acid-base catalysis. KHSO5 reacts quantitatively with Link in an alkaline medium to form the corresponding sulfone-N-oxide: 1 mole of Link requires 3 moles of KHSO5. Methods for the oxidimetric determination of Link were developed using KHSO5 as an analytical reagent: a known excess of the reagent is added and after a specified time, its residual amount is determined by iodometry. The possibility of quantitative determination of the main substance in the substance of Link hydrochloride, as well as the determination of Link hydrochloride solution for injection "Lincomycin-Zdorovye" 300 mg/ml in ampoules of 1 ml and capsules of 0.25 g were shown. RSD does not exceed 1.7%
Synthesis and Characterization of Poly(methyl methacrylate-co-vinyl triethoxysilane) Prepared by Free Radical Polymerization
Get PDFThe copolymerization of methyl methacrylate (MMA) with vinyl triethoxysilane (VTES) was carried out in ethyl cellosolve at 70 ℃ using azobisisobutyronitrile (AIBN) as a free radical initiator. The prepared copolymer was purified and then analysed by FT-IR, NMR, TGA and SEM analyses. FT-IR along with NMR confirm the successful preparation of the copolymer. The prepared copolymer shows better thermal stability than poly(methyl methacrylate). A morphological study was also carried out by SEM analysis. SEM micrographs show that the copolymer surface gets roughened and becomes porous on copolymerization
Study of the Effect of Temperature on the Rheological Characteristics of Composite Fuel
Get PDFThe article is devoted to the study of the patterns of change in the rheological characteristics of composite fuels based on low-ash anthracite at a mass fraction of the solid phase of 40%, an oil phase concentration of Co = 49%, a water concentration of CH2O = 10%, and 1% of a chemical additive with an increase in temperature from 10 to 70 °C. It has been established that the dependence of the rheological characteristics of composite fuel on temperature indicators is complex. When the temperature changes from 20 to 30 °C, a plateau is observed (the change in the Kμt coefficient is ≈0.9), which has a significant deviation from the approximation dependence for calculating the Kμt coefficient. From the data obtained, it can be concluded that this type of fuel can successfully compete with traditional types of liquid fuel
Study of the Antioxidant Activity of Synthetic 3-hydroxyflavone Derivatives by DPPH and Hydrogen Peroxide Methods
Get PDFFlavonoids have good efficacy as antioxidants due to their ability to scavenge free radicals within cells. In our previous study, synthetic flavonoid derivatives (A2-A13) were prepared in vitro through condensation, oxidative cyclization, alkylation and esterification reactions. The antioxidant activity of the alkyl and esterified derivatives of the flavonoid compound (A2) 3-hydroxy-2-(4-[dimethylamino]phenyl) benzo-4-pyrone was studied by two methods: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical inhibition method and inhibition of hydrogen peroxide (H2O2) and compared to the activity of standard antioxidant compounds, ascorbic acid and quercetin. The flavonoids (prepared samples) A2, A5, and A7 showed high activity approaching that of ascorbic acid and quercetin as well-known antioxidants. As for the compounds (A3, A6, A8, A9, A10, A11, A12, A13), which contain an -OH enol group, a benzyl group, and a chlorine group and the acetate group, its effectiveness has decreased significantly
Assessment of the Nature of Dyslipoproteinemias and Correlations of Indicators of General Reactivity and Lipid Metabolism in Patients with Chronic Nonspecific Inflammation of the Reproductive System
Get PDFMetabolic disorders can occur at all levels of biological organization - from molecular and cellular to the level of the organism as a whole. These changes may result from disruptions in hormonal mechanisms, actions of pathogenic factors, or infections. Primary metabolic disorders are the basis of many diseases, such as diabetes, obesity, and atherosclerosis, while secondary disorders accompany most pathological processes. Disruption of lipid metabolism leads to changes in their functions and the development of pathological processes, such as dyslipoproteinemia, and also contributes to the development of atherosclerosis. Various intracellular infectious agents play a significant role in the development of dyslipoproteinemias and atherosclerosis, for example, chlamydia can alter the lipid metabolism in macrophages under the influence of low-density lipoproteins, leading to the formation of 'foam-like' cells. This, in turn, contributes to the development of atheromatous plaques-a favorable environment for chlamydia, where it can survive for an extended period and trigger immunopathological mechanisms