scholarly journals Synthesis and study of the properties of derivatives 4-phenyl-5-(1H-pyrrol-2-yl)-4H-1,2,4-triazole-3-thiols

2018 ◽  
pp. 59-66
Author(s):  
A. S. Gotsulya ◽  
D. P. Verba ◽  
O. I. Panasenko ◽  
Ye. G. Knysh
Keyword(s):  
Heterocyclic System ◽  
Chemical Properties ◽  
Physico Chemical ◽  
Methods Of Synthesis ◽  
Interesting Object ◽  
Physical And Chemical ◽  
Derivatives Of ◽  
Selection Of ◽  
Base Structure ◽  
And Chemical Properties

The successful use of drugs, derivatives of 1,2,4-triazole, creates the conditionsfor the production and investigation of properties of new derivatives of this heterocyclic system. The aim of this work was synthesis and study of physical and chemical properties of new derivatives of 1,2,4-triazole-3-thiol containing synthon of pyrrole. The object of the study was a 4-phenyl-5-(pyrrol-2-yl)-1,2,4-triazole-3-ylthio-R-carbothioamides. To achieve this goal it was necessary to solve following tasks: to conduct the selection of the optimum base structure to determine the most efficient way of chemical modification of the precursor of targeted synthesis, to carry out selection of necessary methods of synthesis, to investigate the physico-chemical properties and to set the structure of the obtained compounds. The synthesis of target products of the reaction was carried out using as starting material pyrrole, which with using the form non-catalytic form of reaction of the Fridel-Crafts was transformed into 2,2,2-trichloro-1-(pyrrol-2-yl), ethanol. The resulting material in the result of reaction of hydrazinolysis was converted into the pyrrol-2-carbohydrazide. The obtained intermediate product was used in the reaction of nucleophilic joining of phenylisothiocyanate with subsequent intramolecular alkaline heterocyclization. Synthesized thiol was used in the reaction of alkylation. The structure of the obtained substances are confirmed by using elemental analysis, 1H-NMR-spectroscopy, and their individuality – chromatographic methods of analysis. The resulting substances are an interesting object for further studies, especially biological activity.

Tailoring microstructures of materials through biomimetics

1993 ◽  
Vol 51 ◽  
pp. 500-501
Author(s):  
Mehmet Sarikaya ◽  
Ilhan A. Aksay
Keyword(s):  
Chemical Properties ◽  
Design And Synthesis ◽  
Structure Sensitive ◽  
Macro Scale ◽  
Methods Of Synthesis ◽  
Successive Level ◽  
Engineering Materials ◽  
Physical And Chemical ◽  
And Chemical Properties ◽  
Synthesis Of Materials

Biomimetics involves investigation of structure, function, and methods of synthesis of biological composite materials. The goal is to apply this information to the design and synthesis of materials for engineering applications.Properties of engineering materials are structure sensitive through the whole spectrum of dimensions from nanometer to macro scale. The goal in designing and processing of technological materials, therefore, is to control microstructural evolution at each of these dimensions so as to achieve predictable physical and chemical properties. Control at each successive level of dimension, however, is a major challenge as is the retention of integrity between successive levels. Engineering materials are rarely fabricated to achieve more than a few of the desired properties and the synthesis techniques usually involve high temperature or low pressure conditions that are energy inefficient and environmentally damaging.In contrast to human-made materials, organisms synthesize composites whose intricate structures are more controlled at each scale and hierarchical order.

scholarly journals Effect of Slice Weight and Soaking Time on the Physico-Chemical Properties of Cassava Flour (Manihotesculentus) used for Bakery Products

2021 ◽  
pp. 10-24
Author(s):  
C. R. Abah ◽  
C. N. Ishiwu ◽  
J. E. Obiegbuna ◽  
E. F. Okpalanma ◽  
C. S. Anarado
Keyword(s):  
Chemical Properties ◽  
Process Variables ◽  
Soaking Time ◽  
Cassava Flour ◽  
Baked Goods ◽  
Cassava Root ◽  
Physico Chemical ◽  
Physical And Chemical ◽  
And Chemical Properties

Quality cassava(Manihotesculentus, Crantz) flour is often influenced by process variables such as slice weight and soaking time which may affect its nutritional quality. In this study, the effect of process variables (slice weight and soaking time) on quality of cassava flour was carried out. Cassava root was peeled, washed and cut into varied sizes (25.86 - 54.14 g) and soaked at varied time (7.03 - 40.97 h). The proximate composition, physical and chemical properties of the flour were carried out using standard methods. The result in our findings showed that slice weight and soaking time had significant increase (p<0.05) on the proximate and physico-chemical properties of the flour.The amylose and amylopectin content of the flour increased with increasing soaking time while the hydrogen cyanide content decreased with increase in soaking time. Overall, the quality cassava flour displayed desirable properties for its incorporation into baked goods.

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 Free-standing spider silk webs of the thomisid Saccodomus formivorus are made of composites comprising micro- and submicron fibers

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Christian Haynl ◽  
Jitraporn Vongsvivut ◽  
Kai R. H. Mayer ◽  
Hendrik Bargel ◽  
Vanessa J. Neubauer ◽  
...  
Keyword(s):  
Spider Silk ◽  
Structural Integrity ◽  
Chemical Properties ◽  
Free Standing ◽  
Physico Chemical ◽  
Physical And Chemical ◽  
Crab Spiders ◽  
Ambush Predators ◽  
The Web ◽  
And Chemical Properties

Abstract Our understanding of the extraordinary mechanical and physico-chemical properties of spider silk is largely confined to the fibers produced by orb-weaving spiders, despite the diversity of foraging webs that occur across numerous spider families. Crab spiders (Thomisidae) are described as ambush predators that do not build webs, but nevertheless use silk for draglines, egg cases and assembling leaf-nests. A little-known exception is the Australian thomisid Saccodomus formivorus, which constructs a basket-like silk web of extraordinary dimensional stability and structural integrity that facilitates the capture of its ant prey. We examined the physical and chemical properties of this unusual web and revealed that the web threads comprise microfibers that are embedded within a biopolymeric matrix containing additionally longitudinally-oriented submicron fibers. We showed that the micro- and submicron fibers differ in their chemical composition and that the web threads show a remarkable lateral resilience compared with that of the major ampullate silk of a well-investigated orb weaver. Our novel analyses of these unusual web and silk characteristics highlight how investigations of non-model species can broaden our understanding of silks and the evolution of foraging webs.

scholarly journals Physical and Chemical Properties and Methods of Control of Pantoprazol Sodium Sesquihydrate (Review)

2020 ◽  
Vol 9 (1) ◽  
pp. 46-53
Author(s):  
V. A. Shelekhova ◽  
K. R. Savelyeva ◽  
S. V. Polyakov ◽  
V. N. Shestakov
Keyword(s):  
Chemical Properties ◽  
Reaction Products ◽  
Chemical Methods ◽  
Spectrophotometric Methods ◽  
Physico Chemical ◽  
Inflammatory Drugs ◽  
Physical And Chemical ◽  
Direct Spectrophotometry ◽  
Methods Of Control ◽  
And Chemical Properties

Introduction. Pantoprazole sodium sesquihydrate is a proton pump inhibitor. This substance is used in the treatment of peptic ulcer of the duodenum or stomach in the acute phase, including those associated with the use of non-steroidal anti-inflammatory drugs.Text. Pantoprazole is sodium 5-(difluoromethoxy)-2-[(RS)-[(3,4-dimethoxypyridin-2-yl)methyl]sulfinyl]benzimidazol-1-ide sesquihydrate in its structure. The substance is readily soluble in water and ethyl alcohol. The identification of pantoprazole is confirmed by infrared absorption spectrophotometry, as well as by a positive reaction to sodium ion. For the assay of this substance chemical and physico-chemical methods are used. The first group of methods includes titration in a non-aqueous medium with perchloric acid and permanganatometry. Physico-chemical methods used for pantoprazole assay are spectrophotometry and HPLC. The most commonly used method is direct spectrophotometry associated with the measurement of optical density at a wavelength of the maximum absorption of pantoprazole in various solvents. In addition, spectrophotometric methods of assay are known, based on the study of the absorption of colored pantoprazode reaction products. The derivative spectrophotometry is used for the analysis of its preparations. The control of the content of impurities and pantoprazole in the substance and its dosage forms is carried out, as a rule, using HPLC.Conclusion. An analysis of the literature has shown that this substance is unstable. Therefore, this feature of pantoprazole must be considered when choosing excipients when developing a dosage form. The preferred method for analyzing pantoprazole preparations is HPLC, since it is possible to determine the substance in the presence of other compounds, which will allow one to control the quantitative content and stability of pantoprazole in the preparation.

scholarly journals Synthesis of Picric Acid at Domestic Scales.

2019 ◽  
Author(s):  
Afshan Saleem ◽  
Noureen Rafi ◽  
Sumara Qasim ◽  
Usama Ashraf ◽  
Nasir Hussain Virk
Keyword(s):  
Ir Spectra ◽  
Physical State ◽  
Picric Acid ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Greenish Yellow ◽  
Yellow Color ◽  
Physical And Chemical ◽  
Derivatives Of ◽  
And Chemical Properties

Picric acid and its derivatives are widely used in various applications/industries. The first synthetic dye was prepared in 1771 using picric acid. It was used to dye silk fabric into greenish-yellow color. In this study, Picric acid and their derivatives were synthesized and characterized by their physical and chemical properties. The derivatives of Picric acid which are considered in this research include Picramic acid and Sodium Picramate. The physical properties like melting point, colors, physical state and solubility of Picric acid and its derivatives were determined and confirmed using IR Spectra. IR spectra proved efficient in scanning and mapping.

scholarly journals Synthesis, physico-chemical properties of 3-thio and 3-thio -4-amino derivatives of 1,2,4-triazole

2019 ◽  
pp. 28-44
Author(s):  
V. V. Parchenko
Keyword(s):  
Chemical Properties ◽  
Biological Properties ◽  
Modern Medicine ◽  
Toxic Substances ◽  
Triazole Derivatives ◽  
Synthetic Drugs ◽  
Physico Chemical ◽  
Methods Of Synthesis ◽  
Amino Derivatives ◽  
Derivatives Of

Modern medicine and pharmacy has at its disposal highly efficient synthetic drugs. Large extent of these drugs accounted for derivatives of 1,2,4-triazole. The purpose of the work was an attempt to summarize the literature in recent years related to the methods of synthesis and study of physico-chemical properties 3-thio- and 3-thio-4-amino derivatives of 1,2,4-triazole. Studies national scientists in recent years indicates prospects of the search in this direction, since this class of organic compounds is interest not only to scientists pharmaceutical, medical and veterinary field, but also among researchers of engineering, metallurgical and agricultural areas. 1,2,4-triazole derivatives are also widely used in practice for optical materials, photosensitizers are used as coloring agents, antioxidants, additives for fuels and oils, some of which are widely used as corrosion inhibitors for controlling various pests in agriculture. In addition, 1,2,4-triazole derivatives belong to the class low toxic or essentially non-toxic substances. The presence of a growing number of publications about methods of synthesis, reactions, physico-chemical and biological properties of 1,2,4-triazole, inspires scientists around the world search for perspective molecules of substituted 1,2,4-triazole. It should be noted that in spite of a sufficient amount of information about the derivatives of 1,2,4-triazole, some issues related to the generalization of data in the literature synthesis presented insufficient.

scholarly journals Some transformations and physicochemical properties of new S-substituted 5-thiophene-(3-ylmethyl)-4R-1,2,4-triazole-3-thiols

2021 ◽  
pp. 50-56
Author(s):  
А. В. Хільковець
Keyword(s):  
Alkaline Medium ◽  
Chemical Properties ◽  
Monochloroacetic Acid ◽  
Esterification Reaction ◽  
Physical And Chemical Properties ◽  
Analysis Methods ◽  
New Compounds ◽  
Physical And Chemical ◽  
Derivatives Of ◽  
And Chemical Properties

Nitrogen-containing heterocyclic compounds are widely represented in modern organic chemistry. A special place among the huge number of substances presented is occupied by derivatives of 1,2,4-triazole due to their uniqueness and prospects. In recent years, these derivatives have remained the object of close attention of both synthetic chemists and researchers engaged in the search for new biologically active substances of a wide spectrum of action, the synthesis of optical materials, dyes, corrosion inhibitors, veterinary drugs, etc. It is known from the literature that the combination of the aromatic heterocycle of thiophene and 1,2,4-triazole is a promising area for research. The result of such combinations is a number of compounds obtained with fairly high yields and a wide range of activities. Thus, further chemical modification of 1,2,4-triazole derivatives by additional administration of a typical thiophene pharmacophore is an urgent task. The aim of the study is to obtain new compounds in a number of S-substituted 5-thiophene-(3-ylmethyl)-4R-1,2,4-triazole-3-thiols and study their physico-chemical properties using complex analysis methods. The study of the physical and chemical properties of the compounds obtained was carried out according to methods that meet the standards of the state pharmacopoeia of Ukraine. The synthesis of new compounds was carried out according to generally accepted methods. The previously obtained 5-thiophene-(3-ylmethyl)-4h-1,2,4-triazole-3-thiol and 5-thiophene-(3-ylmethyl)-4-phenyl-1,2,4-triazole-3-thiol were used as starting compounds. Preparation of thioethanones was performed in an alkaline medium in the presence of methanol. The acids were obtained in an alcohol-alkaline medium with the addition of monochloroacetic acid. To obtain esters, two conventional methods were used. The first method is based on the alkylation in an alkaline-alcohol medium of the starting thiols with isopropyl ester of monochloroacetic acid. The second method is the classical esterification reaction. To confirm the structure and study of the physical and chemical properties, all the resulting compounds were crystallized. As a result, some new compounds that were not previously described were obtained, namely: thioethanones, thioacetamides, thioacetic acids, thioacetates, and a number of other thiopo-derivatives of these initial compounds. The structure and individuality of the obtained molecules were confirmed by elemental analysis (CHNS), IR and 1H NMR spectra. A number of new S-derivatives of 5-thiophene-(3-ylmethyl)-4R-1,2,4-triazole-3-thiols have been obtained. The physical and chemical properties of the obtained compounds are determined and their structure is confirmed using modern analysis methods. Some compounds will be transferred for further research.

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