scholarly journals Phenacylation of 6-Methyl-Beta-Nitropyridin-2-Ones and Further Heterocyclization of Products

Molecules ◽  
2020 ◽  
Vol 25 (7) ◽  
pp. 1682
Author(s):  
Eugene V. Babaev ◽  
Victor B. Rybakov
Keyword(s):  
Pyridinium Salt ◽  
Phenacyl Bromides ◽  
Acidic Conditions ◽  
Phenacyl Derivatives ◽  
Derivatives Of

Reaction between the derivatives of 6-methyl-beta-nitropyridin-2-one and phenacyl bromides was studied, and the yields observed were extremely low. The pyridones were converted via chloropyridines to methoxyderivatives, which were N-phenacylated. N-Phenacyl derivatives of 4,6-dimethyl-5-nitropyridin-2-one under the action of base gave 5-hydroxy-8-nitroindolizine and under acidic conditions gave 5-methyl-6-nitrooxazole[3,2-a]pyridinium salt, which underwent recycization with MeONa to 5-methoxy-8-nitroindolizine.

scholarly journals In Vitro Anti-Candida Activity and Action Mode of Benzoxazole Derivatives

Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 5008
Author(s):  
Monika Staniszewska ◽  
Łukasz Kuryk ◽  
Aleksander Gryciuk ◽  
Joanna Kawalec ◽  
Marta Rogalska ◽  
...  
Keyword(s):  
Transport Process ◽  
Cross Resistance ◽  
Action Mechanism ◽  
Action Mode ◽  
Pleiotropic Action ◽  
Ergosterol Synthesis ◽  
Comparable Activity ◽  
Phenacyl Derivatives ◽  
Derivatives Of

A newly synthetized series of N-phenacyl derivatives of 2-mercaptobenzoxazole, including analogues of 5-bromo- and 5,7-dibromobenzoxazole, were screened against Candida strains and the action mechanism was evaluated. 2-(1,3-benzoxazol-2-ylsulfanyl)-1-(4-bromophenyl)ethanone (5d), 2-(1,3-benzoxazol-2-ylsulfanyl)-1-(2,3,4-trichloro-phenyl)ethanone (5i), 2-(1,3-benzoxazol-2-ylsulfanyl)-1-(2,4,6-trichlorophenyl)ethanone (5k) and 2-[(5-bromo-1,3-benzoxazol-2-yl)sulfanyl]-1-phenylethanone (6a) showed anti-C. albicans SC5314 activity, where 5d displayed MICT = 16 µg/mL (%R = 100) and a weak anti-proliferative activity against the clinical strains: C. albicans resistant to azoles (Itr and Flu) and C. glabrata. Derivatives 5k and 6a displayed MICP = 16 µg/mL and %R = 64.2 ± 10.6, %R = 88.0 ± 9.7, respectively, against the C. albicans isolate. Derivative 5i was the most active against C. glabrata (%R = 53.0 ± 3.5 at 16 µg/mL). Benzoxazoles displayed no MIC against C. glabrata. Benzoxazoles showed a pleiotropic action mode: (1) the total sterols content was perturbed; (2) 2-(1,3-benzoxazol-2-ylsulfanyl)-1-(3,4-dichlorophenyl)ethanol and 2-(1,3-benzoxazol-2-ylsulfanyl)-1-(2,3,4-trichlorophenyl)ethanol (8h–i) at the lowest fungistatic conc. inhibited the efflux of the Rho123 tracker during the membrane transport process; (3) mitochondrial respiration was affected/inhibited by the benzoxazoles: 2-(1,3-benzoxazol-2-ylsulfanyl)-1-(4-chlorophenyl)ethanol and 2-(1,3-benzoxazol-2-ylsulfanyl)-1-(4-bromophenyl)ethanol 8c–d and 8i. Benzoxazoles showed comparable activity to commercially available azoles due to (1) the interaction with exogenous ergosterol, (2) endogenous ergosterol synthesis blocking as well as (3) membrane permeabilizing properties typical of AmB. Benzoxazoles display a broad spectrum of anti-Candida activity and action mode towards the membrane without cross-resistance with AmB; furthermore, they are safe to mammals.

scholarly journals Synthesis and anticonvulsant activity of 6-methyl-2-((2-oxo-2-arylethyl)thio)pyrimidin-4(3 H)-one derivatives and products of their cyclization

Pharmacia ◽  
2019 ◽  
Vol 66 (3) ◽  
pp. 141-146
Author(s):  
Hanna Severina ◽  
Olga O. Skupa ◽  
Natalya I. Voloshchuk ◽  
Marharyta M. Suleiman ◽  
Victoriya A. Georgiyants
Keyword(s):  
Sulphuric Acid ◽  
Anticonvulsant Activity ◽  
Sodium Methoxide ◽  
Structure Activity ◽  
Phenacyl Bromides ◽  
Pharmacological Screening ◽  
High Yields ◽  
Derivatives Of

The alkylation of 6-methyl-2-thioxo-2,3-dihydro-1H-pyrimidine-4-one phenacyl bromides under different conditions was investigated. It was found that during the reaction in the medium of DMF/K2CO3 a mixture of 2-(2-aryl-2-oxoethyl)thio-6-methyl-pyrimidine-4(3H)-one and 3-hydroxy-3-aryl-7-methyl-2,3-dihydro-5H-thiazolo[3,2-a]pyrimidine-5-one was formed. The holding of the resulting mixture in the concentrated sulphuric acid leads to the formation of cyclization products - derivatives of 3-aryl-7-methyl-5H-thiazolo[3,2-a]pyrimidin-5-one with high yields. Individual S-alkylated derivatives – 2-(2-aryl-2-oxoethyl)thio-6-methyl-pyrimidine-4(3H)-one - were obtained by reacting in methanol in the presence of sodium methoxide. Pharmacological screening of synthesized compounds for anticonvulsant activity on the model of pentylenetetrazole seizures in rats was carried out and some regularity “structure-activity” was established.

Original Recyclization of S-Phenacyl Derivatives of 4-Acylamino-2-mercapto-1,3-oxazoles and Their Analogues.

ChemInform ◽  
2007 ◽  
Vol 38 (37) ◽  
Author(s):  
Andrei G. Balia ◽  
Aleksandr G. Belyuga ◽  
Vladimir S. Brovarets ◽  
Aleksandr N. Vasylenko ◽  
Aleksandr V. Turov ◽  
...  
Keyword(s):  
Phenacyl Derivatives ◽  
Derivatives Of

scholarly journals Cyclotrimerization of 3-R-1,2,4-Triazin-5(4H)-ones with Cyclic Ketones

2010 ◽  
Vol 65 (11) ◽  
pp. 1359-1362 ◽  
Author(s):  
Ilya N. Egorov ◽  
Igor S. Kovalev ◽  
Vladimir L. Rusinov ◽  
Oleg N. Chupakhin
Keyword(s):  
Cyclic Ketones ◽  
Acidic Conditions ◽  
Derivatives Of

New heterocyclic tetracyclic systems were synthesized. Interaction between 3-R-1,2,4-triazin- 5(4H)-ones and cyclic ketones under acidic conditions leads to the formation of zwitterion derivatives of 5,6,7,8,9,10,11,12-octahydro-[1,2,4]triazino[1,6- ƒ ]phenanthridine and 1,2,3,6,7,8-hexahydro-bicyclopenta[ b,d]pyrido[1,2- ƒ ][1,2,4]triazine.

Oxyhalogen–sulfur chemistry — Kinetics and mechanism of the bromate oxidation of cysteamine

2008 ◽  
Vol 86 (5) ◽  
pp. 416-425 ◽  
Author(s):  
Moshood K Morakinyo ◽  
Edward Chikwana ◽  
Reuben H Simoyi
Keyword(s):  
Oxidation Product ◽  
Reducing Agent ◽  
Kinetics And Mechanism ◽  
Molecular Bromine ◽  
Sulfur Chemistry ◽  
Diffusion Controlled ◽  
Hypobromous Acid ◽  
Acidic Conditions ◽  
Acid Toxicity ◽  
Derivatives Of

The kinetics and mechanism of the oxidation of the biologically important molecule, cysteamine, by acidic bromate and molecular bromine have been studied. In excess acidic bromate conditions, cysteamine is oxidized to N-brominated derivatives, and in excess cysteamine the oxidation product is taurine according to the following stoichiometry: BrO3– + H2NCH2CH2SH → H2NCH2CH2SO3H + Br–. There is quantitative formation of taurine before N-bromination commences. Excess aqueous bromine oxidizes cysteamine to give dibromotaurine: 5Br2 + H2NCH2CH2SH + 3H2O → Br2NCH2CH2SO3H + 8Br– + 8H+, while excess cysteamine conditions gave monobromotaurine. The oxidation of cysteamine by aqueous bromine is effectively diffusion-controlled all the way to the formation of monobromotaurine. Further formation of dibromotaurine is dependent on acid concentrations, with highly acidic conditions inhibiting further reaction towards formation of dibromotaurine. The formation of the N-brominated derivatives of taurine is reversible, with taurine regenerated in the presence of a reducing agent such as iodide. This feature makes it possible for taurine to moderate hypobromous acid toxicity in the physiological environment.Key words: cysteamine, hypobromous acid, toxicities, antioxidant.

Nitration of 3,4-Dimethylacetophenone and 3,4-Dimethylbenzophenone. Formation and Rearomatization of Adducts

1975 ◽  
Vol 53 (11) ◽  
pp. 1570-1578 ◽  
Author(s):  
Alfred Fischer ◽  
Colin Campbell Greig ◽  
Rolf Röderer
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Nitro Group ◽  
Nitrous Acid ◽  
Main Product ◽  
Intermediate Formation ◽  
Nitro Derivatives ◽  
Acidic Conditions ◽  
Cis And Trans ◽  
Derivatives Of

Nitration of 3,4-dimethylacetophenone in acetic anhydride gives a mixture of cis-and trans-2-acetyl-4,5-dimethyl-4-nitro-1,4-dihydrophenyl acetate as the main product, together with 3,4-dimethyl-2-, 3,4-dimethyl-5-, and 3,4-dimethyl-6-nitroacetophenone. Analogous products are obtained from 3,4-dimethylbenzophenone. Rearomatization of the adducts under mildly acidic conditions occurs via 1,4-elimination of nitrous acid to form 2-acetyl- and 2-benzoyl-4,5-dimethylphenyl acetate, respectively. In strongly acidic conditions elimination of acetic acid accompanied by 1,2- and 1,3-shifts of the nitro group occurs to form the 2- and 5-nitro derivatives of the parent ketones. The rearomatization to the nitro derivatives involves the intermediate formation of an ipso-cyclohexadienyl cation which may be trapped by anisole or mesitylene to form biphenyl derivatives.

scholarly journals Synthesis and spectroscopic properties of β-triazoloporphyrin–xanthone dyads

2015 ◽  
Vol 11 ◽  
pp. 1434-1440 ◽  
Author(s):  
Dileep Kumar Singh ◽  
Mahendra Nath
Keyword(s):  
Fluorescence Spectra ◽  
Photophysical Properties ◽  
Bathochromic Shift ◽  
Cycloaddition Reaction ◽  
Spectroscopic Characterization ◽  
Spectroscopic Properties ◽  
Dipolar Cycloaddition ◽  
Free Base ◽  
Acidic Conditions ◽  
Derivatives Of

A novel series of β-triazoloporphyrin–xanthone conjugates and xanthone-bridged β-triazoloporphyrin dyads has been synthesized in moderate to good yields through Cu(I)-catalyzed Huisgen 1,3-dipolar cycloaddition reaction of copper(II) 2-azido-5,10,15,20-tetraphenylporphyrin or zinc(II) 2-azidomethyl-5,10,15,20-tetraphenylporphyrin with various alkyne derivatives of xanthones in DMF containing CuSO4 and ascorbic acid at 80 °C. Furthermore, these metalloporphyrins underwent demetalation under acidic conditions to afford the corresponding free-base porphyrins in good to excellent yields. After successful spectroscopic characterization, these porphyrins have been evaluated for their photophysical properties. The preliminary results revealed a bathochromic shift in the UV–vis and fluorescence spectra of these porphyrin–xanthone dyads.

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