Monocyclic and cascade rearrangements of furoxans

2004 ◽  
Vol 76 (9) ◽  
pp. 1691-1703 ◽  
Author(s):  
N. N. Makhova ◽  
I. V. Ovchinnikov ◽  
A. S. Kulikov ◽  
S. I. Molotov ◽  
E. L. Baryshnikova
Keyword(s):  
Triazole Ring ◽  
Alternative Methods ◽  
Alkyl Aryl ◽  
Thermally Induced ◽  
Triazole Derivatives ◽  
The Third ◽  
Azo Group ◽  
Derivatives Of ◽  
Cascade Type

Monocyclic rearrangements of azoles are extensively studied as alternative methods for the preparation of new heterocyclic systems. The present work is devoted to investigation of monocyclic and cascade rearrangements of 1,2,5-oxadiazole 2-oxide (furoxan) derivatives. It was found during investigations that rearrangements of furoxan ring had some peculiarities in comparison with analogous rearrangements of other azoles. Therefore, three different kinds of rearrangements were found. The first of them occurred through a dinitroso-ethylene intermediate and resulted in the synthesis of 1,2,3-triazole 1-oxides [oximes of 5-acetyl-4-phenyl(methyl)-2-phenyl-2H -1,2,3-triazole 1-oxides and 2-(furoxan-4-yl)-4-nitro-5-R-2H -1,2,3-triazole 1-oxides ]by thermal recyclization accordingly of 3-methyl-4-acetyl(benzoyl)furoxans phenylhydrazones and 3,3'-(R)-disubstituted-4,4'-azofuroxans. The latter reaction was performed in an oxidizing medium. The second kind of rearrangement (classical variant) was the synthesis of new azoles containing the 1-nitroalkyl substituent. These rearrangements were performed using three examples: base-induced interconversion of furoxanyl ketone phenylhydrazones into 5-(1-nitroalkyl)-2H-1,2,3-triazole derivatives and of 1-alkyl(aryl)-3-(furoxan-4-yl)amidines into 1-substituted 3-(1-nitroalkyl)-1,2,4-triazoles as well as a thermally induced rearrangement of 4-thioureido-3-R-furoxans into derivatives of 5-amino-3-(1-nitroalkyl)-1,2,4-thiadiazole including (5-amino-1,2,4-thiadiazol-3-yl)nitro-formaldehyde arylhydrazones (where R =N=N –Ar). Rearrangements of the third kind were those of the cascade type. Three new cascade rearrangements of azofuroxan derivatives [3,3'-azo-4,4'-bis(acetylamino)furoxans, 3-arylazo-4-acetylaminofuroxans, and 3-arylazo-4-(3- ethoxycarbonylureido)furoxans] into 4-amino-5-nitro-2H-1,2,3-triazole derivatives were discovered. These three reactions were assumed to include two consecutive (cascade) rearrangements: a 1,2,4-oxadiazole ring was formed at the first step and then transformed into a 1,2,3-triazole ring with the participation of an azo group.

scholarly journals Review of antibacterial and antifungal activity of 1,2,4-triazole derivatives

2018 ◽  
pp. 63-68
Author(s):  
Т. О. Samura
Keyword(s):  
Antifungal Activity ◽  
Heterocyclic Compounds ◽  
Practical Importance ◽  
Complex Compounds ◽  
Biologically Active ◽  
Alkyl Aryl ◽  
Triazole Derivatives ◽  
Antimicrobial And Antifungal Activity ◽  
Antibacterial And Antifungal ◽  
Derivatives Of

Derivatives of 1,2,4-triazole is a very  perspective class of heterocyclic compounds which have high therapeutic effectiveness. The main direction of research on these derivatives are antifungal, antiviral, antibacterial, soothing, hypnotic, anticonvulsant, anti-inflammatory and other activities. The aim was to analyze literature data and generalize recent advances in the study of antimicrobial and antifungal action of 1,2,4-triazole derivatives which can help to create new biologically active substances of this type of activity. Bibliosemantical method, systems thinking and the results of our own research were used in the work. The results of the literature review of antimicrobial and antifungal activity among new alkyl, aryl and heteryl derivatives of 1,2,4-triazole and among complex compounds, which contain 1,2,4-triazole are as ligands were analyzed and systematized. Some dependence of this type of activity on specialty of chemical structure of heterocyclic system derivatives was specified. Perspective of purposeful synthesis of new derivatives of 1,2,4-triazole and products of their transformation as available object for studying biological activity and expanding knowledge about antimicrobial and antifungal activity of this class of heterocyclic compounds were shown with informational analysis. Topicality and practical importance of finding biologically active compounds and receiving biologically active substance by synthesis of new derivatives of 1,2,4-triazole with high antimicrobial activity in relation to gram-negative and gram-positive bacteria were demonstrated.

Synthesis of Novel 1,2,3-Triazole Derivatives of Isocoumarins and 3,4-Dihydroisocoumarin with Potential Antiplasmodial Activity In Vitro

2020 ◽  
Vol 16 ◽  
Author(s):  
Lucas da Silva Santos ◽  
Matheus Fillipe Langanke de Carvalho ◽  
Ana Claudia de Souza Pinto ◽  
Amanda Luisa da Fonseca ◽  
Julio César Dias Lopes ◽  
...  
Keyword(s):  
Triazole Ring ◽  
Antiplasmodial Activity ◽  
World Health ◽  
Dipolar Cycloaddition ◽  
Terminal Alkynes ◽  
The World ◽  
Ic50 Values ◽  
Derivatives Of ◽  
Active Substances

Background: Malaria greatly affects the world health, having caused more than 228 million cases only in 2018. The emergence of drug resistance is one of the main problems in its treatment, demonstrating the urge for the development of new antimalarial drugs. Objective: Synthesis and in vitro antiplasmodial evaluation of triazole compounds derived from isocoumarins and a 3,4- dihydroisocoumarin. Method: The compounds were synthesized in 4 to 6-step reactions with the formation of the triazole ring via the Copper(I)-catalyzed 1,3-dipolar cycloaddition between isocoumarin or 3,4-dihydroisocoumarin azides and terminal alkynes. This key reaction provided compounds with an unprecedented connection of isocoumarin or 3,4-dihydroisocoumarin and the 1,2,3-triazole ring. The products were tested for their antiplasmodial activity against a Plasmodium falciparum chloroquine resistant and sensitive strains (W2 and 3D7, respectively). Results: Thirty-one substances were efficiently obtained by the proposed routes with an overall yield of 25-53%. The active substances in the antiplasmodial test displayed IC50 values ranging from 0.68-2.89 μM and 0.85-2.07 μM against W2 and 3D7 strains, respectively.

scholarly journals Third derivatives of the integrable part of an asteroid Hamiltonian

2007 ◽  
pp. 53-60 ◽  
Author(s):  
R. Pavlovic
Keyword(s):  
Third Order ◽  
Geometrical Condition ◽  
The Third ◽  
Derivatives Of ◽  
Quasi Convexity ◽  
Explicit Expressions

To apply the theorem of Nekhoroshev (1977) to asteroids, one first has to check whether a necessary geometrical condition is fulfilled: either convexity, or quasi-convexity, or only a 3-jet non-degeneracy. This requires computation of the derivatives of the integrable part of the corresponding Hamiltonian up to the third order over actions and a thorough analysis of their properties. In this paper we describe in detail the procedure of derivation and we give explicit expressions for the obtained derivatives. .

Chemical modification and Physicochemical properties of new derivatives 5-(thiophen-3-ilmethyl)-4-R1-1,2,4-triazole-3-thiol

2021 ◽  
pp. 4621-4629
Author(s):  
O.A. Bihdan ◽  
V.V. Parchenko
Keyword(s):  
Physicochemical Properties ◽  
High Reactivity ◽  
Biologically Active Compounds ◽  
Biologically Active ◽  
Active Compounds ◽  
Triazole Derivatives ◽  
Pharmaceutical Ingredients ◽  
Current Trends ◽  
Wide Range ◽  
Derivatives Of

Current trends in the search for new biologically active compounds among synthetic molecules have arguably proved a priority in studies of the heterocyclic 1,2,4-triazole system. For many years, 1,2,4-triazole derivatives remain the object of close attention of scientists of various scientific fields. The unique properties of 1,2,4-triazole derivatives include high reactivity, which allows different modification of this system, practical absence of toxicity of these derivatives and the presence of a wide range of biological, pharmacological properties, which in the complex provides the prerequisites for the creation of new biologically active compounds, and in the future, active pharmaceutical ingredients (AFI). The aim of our work is to investigate some transformations in a number of derivatives of 5-(thiophen-3-ylmethyl) -4-R1-1,2,4-triazole-3-thiol, to study the physicochemical properties of the new synthesized compounds. A well-known fact remains the successful attempt of many scientists involved in the study of the heterocyclic 1,2,4-triazole system to synthesize potential biologically active compounds. The process of creating new molecules is very painstaking and requires considerable effort. The chemical approaches for the synthesis of the starting compounds required for further transformations are well known and described. Therefore, we used the corresponding N-R1-2 as intermediates for the synthesis of new 5-(thiophen-3-ylmethyl) -4-R1-1,2,4-triazole-3-thiols appropriate ones were used N-R1-2-(2-(thiophen-3-yl) acetyl) hydrazinocarbothioamide.

Anticancer, antimicrobial and antioxidant potential of sterically tuned bis-N-heterocyclic salts

2018 ◽  
Vol 74 (1-2) ◽  
pp. 17-23 ◽  
Author(s):  
Noor ul Huda ◽  
Shamsul Islam ◽  
Muhammad Zia ◽  
Kainaat William ◽  
Fakhar i Abbas ◽  
...  
Keyword(s):  
Breast Adenocarcinoma ◽  
Benzimidazole Derivatives ◽  
Alkyl Aryl ◽  
Cytotoxic Compound ◽  
Sulforhodamine B ◽  
Hct 116 ◽  
Mrsa Strains ◽  
Pharmacological Potential ◽  
Derivatives Of ◽  
Lipophilic Character

AbstractThe current study was conducted to evaluate the antimicrobial, antioxidant, antileishmanial and cytotoxic potential of designed derivatives of 1,1′-(1,3-phenylenebis(methylene))bis(3-alkyl/aryl-1H-benzimidazol-3-ium) salts. The antibacterial potential of the test compounds was investigated againstStaphylococcus aureus, Pseudomonas aeruginosaand two methicillin-resistantS. aureus(MRSA) strains (MRSA10, MRSA11), where compound6showed the best results. For brine shrimp lethality bioassay (BSLB), compound6again showed up to 100% mortality at 200 μg/mL and 56.7% mortality at 6.25 μg/mL. Antileishmanial assay was performed againstLeishmania tropicaat 20 μg/mL dosage, where6showed the most promising activity with 16.26% survival (83.74% mortality; IC50=14.63 μg/mL). The anticancer potential of the selected benzimidazole derivatives was evaluated against two selected cell lines (human colorectal cancer, HCT-116 and breast adenocarcinoma, MCF-7) using sulforhodamine B (SRB) assay. Compound6was found to be the most effective cytotoxic compound with 75% inhibition of HCT-116 proliferation at 1 mg/mL concentration. Succinctly,6exhibited impressive pharmacological potential that might be attributed to its higher lipophilic character owing to the longer N-substituted alkyl chains when compared to the other test compounds.

scholarly journals Synthesis and Evaluation Antibacterial Activity of Some New Substituted 5-Bromoisatin Containing Five, Six Heterocyclic Ring

2016 ◽  
Vol 13 (2) ◽  
pp. 345-359
Author(s):  
Baghdad Science Journal
Keyword(s):  
Heterocyclic Ring ◽  
Absolute Ethanol ◽  
Synthesis Process ◽  
Triazole Derivatives ◽  
Amide Derivatives ◽  
Heterocyclic Derivatives ◽  
Acid Anhydrides ◽  
Specific Reactions ◽  
Derivatives Of ◽  
Product Compound

This research includes the synthesis of some new different heterocyclic derivatives of 5-Bromoisatin. New sulfonylamide, diazine, oxazole, thiazole and 1,2,3-triazole derivatives of 5-Bromoisatin have been synthesized. The synthesis process started by the reaction of 5-Bromoisatin with different reagents to obtain schiff bases of 5-Bromoisatin intermediate compounds(1, 8, 19) by using glacial acetic acid as a catalyst in three routes. The first route, 5-Bromoisatin reacted with p-aminosulfonylchloride to product compound(1), then converted to sulfonyl amide derivatives(2-7) by the reaction of compound(1) with different substituted primary aromatic amine in absolute ethanol. The second route includes the reaction of 5-Bromoisatin reacted with ethyl glycinate to give 5-bromo-3-(Ethyl imino acetate)-2-oxo indole(8), which undergo react with hydrazine hydrate 80% to obtain hydrazine derivatives(9) that react with different acid anhydrides to obtain diazine derivatives(10-14). Also compound(8) reacts with urea and thiourea to give compounds(15,16) which undergo cyclization with p-bromophenacylbromide in absolute ethanol as a solvent to obtain oxazole (17) and thiazole (18), respectively. The third route included the reaction of 5-Bromoisatin with p-phenylenediamine in ethanol to obtain compound(19) which is converted to new substitutes 1,2,3-triazole derivatives(22,23) by diazotation of compound(19) and treating the resulted salt(20) with sodium azid, then acetylaceton or ethylacetoacetate, respectively. Newly synthesized compounds were identified by spectral methods. (FTIR, 1H-NMR, 13C-NMR) and measurements of some of its physical properties and also some specific reactions. Furthermore the effects of the synthesized compounds were studied on some strains of bacteria.

scholarly journals Straightforward synthesis of enantiomerically pure 1,2,3-triazoles derived from amino esters

2018 ◽  
Vol 16 (17) ◽  
pp. 3168-3176 ◽  
Author(s):  
Gastón Silveira-Dorta ◽  
Sampad Jana ◽  
Lucie Borkova ◽  
Joice Thomas ◽  
Wim Dehaen
Keyword(s):  
Amino Acids ◽  
Enantiomerically Pure ◽  
Triazole Derivatives ◽  
Amino Esters ◽  
Good Yielding ◽  
Derivatives Of

An easy, good-yielding access to functionalized enantiomerically pure 1,2,3-triazole derivatives of amino acids using commercially available ketones and amino esters is described.

Aberrations of Volume Cylindrical Holographic Optical Element

2013 ◽  
Vol 8 (3) ◽  
pp. 6-12
Author(s):  
Yuriy Batomunkuev
Keyword(s):  
Refractive Index ◽  
Characteristic Function ◽  
Optical Element ◽  
Thermally Induced ◽  
The Third ◽  
Holographic Optical Element ◽  
Seventh Order ◽  
Chromatic Aberrations ◽  
Cylindrical Volume ◽  
Analytical Expressions

The analytical expressions allowed to calculate the third-, fifth- and seventh-order monochromatic and chromatic aberrations are obtained for the cylindrical volume holographic optical element by method of the characteristic function. The formulas for coefficients of third-, fifth- and seventh-order aberrations are presented. It is noted that coefficients of the aberrations arising because of photo induced, thermally induced and deformation changes of refractive index and of sizes of the cylindrical volume holographic optical element can be isolated in these coefficients. It is shown that width of the working spectral range for reflection cylindrical volume holographic optical element is inversely proportional to its thickness and for transmission holographic element is inversely proportional to square its thickness

Algorithm for implementation of the «third decision scheme» of increasing the efficiency of search and synchronization of difficult broadband noise like signals

2021 ◽  
Author(s):  
I.I. Snytkin ◽  
T.I. Snytkin
Keyword(s):  
Central Element ◽  
Broadband Noise ◽  
Telecommunication Networks ◽  
Complex Signals ◽  
The Third ◽  
Recurrent Sequences ◽  
Decision Scheme ◽  
Code Structure ◽  
Wideband Signals ◽  
Derivatives Of

The construction of telecommunication networks with a guaranteed level of quality of service involves assessing and ensuring the security of both the networks themselves and information flows from unauthorized access and various kinds of interference, in particular at the 1st (physical) level of the network. In this regard, research in the field of creating recurrent code sequences with improved systemic, correlation, secretive, imitation-resistant properties is constantly relevant. In particular, research in the development and application of derivative nonlinear recurrent sequences, as a central element in the developed theory of the «third decision scheme». Goal of the work is to develop an algorithm for increasing the efficiency of search and synchronization of broadband signals in the form of double derivatives of nonlinear recurrent sequences, which directly uses the features of their code structure, the properties of determinism of their auto- and cross-correlation functions. The results of the research and development of the efficiency of the algorithm for accelerated search and synchronization of broadband complex signals in the form of phase-shift keyed derivatives of nonlinear recurrent sequences, which implements the principles of the «third decision schema» The developed algorithm, based on the use of double derivatives of nonlinear recurrent sequences as wideband signals, can be applied in the construction of promising packet radio networks.

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