French-Ukrainian Journal of Chemistry
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Chemical Characterization and Antioxidant Activity of Cedrus atlantica Manetti Tar (Atlas Cedar Tar)
Get PDFCedrus atlantica Manetti Tar was analyzed by gas chromatography coupled to mass spectrometry, it was subjected to analyzes to know their total polyphenolic and condensed tannins contents, also their Ferric-reducing antioxidant power and Total antioxidant capacity. Chemical characterization identified 88 constituents where Himachalene and α-atlantone isomers (14.51 % - 4.07 %), Calacorene (3.52 %) and ar-Turmerone 3.35 %, were the major components, the total polyphenolic content and condensed tannins contents were 57.15 ± 0.15 milligrams equivalent of gallic acid /g tar and 4.41 ± 0.05 milligrams equivalent of catechin /g tar respectively .This extract showed remarkable Ferric-reducing antioxidant power with effective concentration equal to 50 ± 0.075 mg /mL ± 0,00028 and total antioxidant capacity equal to 262.75 mg equivalents of ascorbic acid /g tar ± 14,43. The experimental results indicated that our tar has promotive antioxidant activity
Potassium Carbonate Assisted Synthesis Of α, β, γ, δ-Unsaturated Ketones
Get PDFThe Cinnamylideneacetophenones derivative is shows important medicinal properties and intermediate in organic synthesis. Several substituted α, β, γ, δ-Unsaturated Ketones were prepared in high yield and purity by direct reaction of substituted cinnamaldehyde and ketones in the presence of potassium carbonate as a base in ethanol at 50ºC. The merit of the method is short reaction times, high yield, easy work-up and purification process, inexpensive and easily available catalyst
The feasibility of using red mud in coatings based on glyptal resins
Get PDFThe possibility of industrial waste – alkaline red mud to be used as the filler of glyptal resins and coatings thereof is considered. It was determined that the most effective way of compounding of said components was in situ combinations during the synthesis of the polymer, providing systems with filling factor up to 36 wt.% with decreased moisture absorption ability in comparison to the initial resin. It was demonstrated that the most probable cause of this performance increase is the formation of chemical bonds between the hydroxyl groups of glyptal and weak van der Waals bonds between the carbonyl group of the resin and surface groups on red mud
Grafting of amino groups onto carbon fibers by bromination followed by ammonolysis
Get PDFBecause of the low content of chelating groups onto carbon fibers (CFs), their adsorptive parameters are poor, and this has negative effects on their applications as lightweight sorbents. In this work, we established a modification method to incorporate amine groups into carbon fiber surfaces by bromination followed by ammonolysis to create an interfacial layer which can adsorb heavy metal ions from solutions. The changed chemical composition, surface morphology, and thermal stability were investigated. Thermoprogrammed desorption mass-spectrometry and thermal analysis showed thermal transformation and interplay between forms of the grafted bromine groups of 0.5 mmol/g and the resulting amino groups of 0.44–0.56 mmol/g. After grafting, the surface chemistry parameters were improved due to the covalent bonding and grafting of the amine groups as interface modifier. Scanning electron microscopy observation also confirmed that the surface morphology maintains the same, without impairment of fiber properties. This work is therefore a beneficial approach towards enhancing the adsorption parameters by controlling the interface layer of CFs
Synthesis some 4-substituted 9,10-anthraquinones
Get PDFNew 4-substituted 9,10-anthraquinones (6 compouds) with amino derivations fragments were synthesized through the substitution of the bromaminic acid by amines using the Ullmann coupling reaction. The structures of the synthesized compounds were determined using LC-MS, 1H NMR, 13C NMR spectroscopy, and elemental analysis data
Iodometric determination of cystamine dihydrochloride in tablets using diperoxyadipic acid
Get PDFThe kinetics of cystamine dihydrochloride oxidation by diperoxyadipic acid (DPAA) was studied in aqueous buffer solutions of pH 2.9, 6.9, 8.0, 8.5 and 9.2 under second-order conditions at the temperature 293 K. The second order rate constants, k (L mol−1 min−1) were calculated from kinetic values. A suitable mechanism scheme based on these observations was proposed. The possibility of application of DPAA as reagent for oxidimetric determination of cystamine dihydrochloride in tabtets was investigated. Cystamine dihydrochloride was determined by indirect titration with DPAA. The required amount of Cystamine dihydrochloride was dissolved in water, pH 8.0 buffer solution and DPAA solution was added. After 7 min, the solution was acidified. The excess DPAA was determined via iodometric titration. The advantages of the applied analytical techniques in the determination of cystamine dihydrochloride in tablets «Cystamine 0.2 g» was presented. The recovery of сystamine dihydrochloride was 99.32±1.45%. A paired t-test showed that all results obtained for bulk drug and in tablets «Cystamine 0.2 g», using the proposed procedure and the official procedure respectively, agreed at the 95% confidence level
Unusual in Water Multicomponent Reaction of 3-Amino-5-methylpyrazole, Acetylacetone and Aldehyde
Get PDFMulticomponent reaction of 3-amino-5-methylpyrazole, aliphatic aldehyde (paraformaldehyde or acetaldehyde) and acetylacetone in water by conventional heating, microwave or ultrasound activation undergoes on molar amounts of reagents 2:1:2, respectively, leads bis(2,5,7-trimethylpyrazolo[1,5-a]pyrimidin-6-yl)-substituted methane or to corresponding 1,1-bis-substituted ethane
The Study of the Composition of Chloroform Fraction of Anemone nemorosa L.
Get PDFExpanding the range of herbal drugs is among the priorities of the modern pharmacy. The analysis presented in this article is drawn from a broader qualitative study examining the composition of Anemone nemorosa L. chloroform fraction. The study revealed 38 compounds, and 32 of them were identified. The investigated lipophilic extract has an antimicrobial activity both in terms of gram-positive and gram-negative microorganisms. The maximal antimicrobial action of the investigated extract was shown to Escherichia coli. The significant content of biologically active substances in the lipophilic volatile fraction of Anemone nemorosa indicates the prospects for further study
A new oxidative derivatization method for spectrophotometric determination of Periciazine in pharmaceutical preparations
Get PDFA new the oxidative derivatization method by means of peroxoacid for the indirect spectrophotometric determination of Periciazine is presented. A potassium hydrogenperoxymonosulfateas a derivatizing agent for Periciazine, yielding the absorbative Periciazine sulfoxide at λmaх=362 nm is proposed. This reaction product was successfully employed for spectrophotometric determination of the Periciazine. The UV spectrophotometric determination of the Periciazine as its sulfoxide proved to be the more simple and selective method. Limit of quantification (LOQ=10S) is 2.8 µg·mL-1. The common excipients employed do not interfere in the determination of phenothiazine drug. Results of analysis of the drug dosage forms by the proposed method are in good agreement with those of the official method. RSD=1.76 % (δ <RSD)
Investigation of aspects of the interaction of the indicators of lipid exchange, trombocitarian block of hemostasis, total body reactivity and their influence on the psychosomatic harmonization of the man in chronic inflammatory processes
Get PDFFor the first time on the basis of clinical and laboratory researches were revealed the correlation of indicators of lipid metabolism, platelet level of hemostasis and general reactivity in patients with chronic inflammatory processes of the genital system. The new pathogenetic aspects of the course of inflammatory diseases have been established. It has been shown that chronic inflammatory process is accompanied by disorders of lipid metabolism. The degree of severity of these changes depends on the severity of the inflammatory process, the reduction of phagocytic activity of polymorphonuclear leukocytes and the activation of macrophage and specific cellular mechanisms, accompanied by auto-intoxication. It is established that the frequency of atherogenic dyslipoproteinemias, as well as the intensity of lipid peroxidation increases in accordance with the increase age of the examined patients. Most atherogenic dyslipoproteinemias are found in patients with viral and chlamydial infections. The summarized data of the correlation analysis allow us to establish that the growth of atherogenic properties of blood plasma of patients with chronic inflammatory processes of the reproductive system occurs in accordance with the increase of adhesive-aggregation properties of platelets and damage of the vascular endothelium. These shifts occur in parallel with the predominance of the monocyte-macrophage linkage of phagocytosis against the background of reduced activity of neutrophils and cellular mechanisms of development of immunopathological reactions