Reaction Of Azoles Research Articles

Sulfite-Promoted Synthesis of N-Difluoromethylthioureas via the Reaction of Azoles with Bromodifluoroacetate and Elemental Sulfur.

A sulfite-promoted transformation of azoles into N-difluoromethylthioureas through N-difluoromethylation and sulfuration has been developed. In this reaction, inexpensive ethyl bromodifluoroacetate and nontoxic elemental sulfur were used as the difluoromethylation and sulfuration reagents, respectively. A variety of azoles, including benzimidazoles, imidazoles, and triazoles, performed well to afford a broad range of azole thioureas in moderate to good yields.

The synthesis and the biological activity of azolylthioacetic acids

The review systematizes the published data concerning the methods of synthesis of azoles (imidazoles, oxazoles, thiazoles, pyrazoles, triazoles, and tetrazoles) functionalized by the carboxymethyl thiol fragment; the results of studies of the biological activity of this class of compounds have been also analysed. Today the main directions for the synthesis of azolylthioacetic acids and their derivatives are reactions of azoles that contain the thiol group with haloacetic acids and their derivatives, and the nucleophilic substitution of halogen in the haloazoles under the action of thioglycolic acid. Moreover, the addition of thioles to multiple bonds, activated with electron withdrawing groups has found its application together with formation of the azole cycle from heterofunctional systems that already contain the component of thioacetic acid. To obtain polyfunctional derivatives of azolylthioacetic acids the modification of azole functional groups that already contain the fragment of thioacetic acid is sometimes used. The summary of the published data gives strong reasons to assert that the derivatives of azolylthioacetic acids are characterized by diverse biological effects. For instance, they are characterized by the antioxidant, hypoglycemic, antitubercular, analgesic, antiviral, antimicrobial, and antifungal activity. The material analysed indicates that the search for new bioactive compounds among the azolylthioacetic acids is very promising.

Structure and NMR properties of 6‐substituted‐5,6‐dihydrobenzo[c]phenanthridine alkaloids

We report a preparation of new 6‐substituted‐5,6‐dihydrobenzo[c]phenanthridines by the reaction of azoles with quaternary benzo[c]phenanthridine alkaloids sanguinarine and chelerythrine. The prepared compounds have been characterized by NMR spectroscopy, mass spectrometry, and single‐crystal X‐ray diffraction. Conformational behaviors of carbazole derivatives in solution have been investigated by low‐temperature NMR experiments. Barriers to rotation around newly formed C6–N bonds were determined to be 12–13 kcal/mol. Quantum chemical calculations have been used to reproduce the experimental observations. Large structural effects on several 1H NMR resonances were observed experimentally, analyzed by Density Functional Theory (DFT) calculations at B3LYP/6‐311+G(d,p)/PCM level, and interpreted by ring‐current effects of the benzo[c]phenanthridine and carbazole units. Copyright © 2013 John Wiley & Sons, Ltd.

Reaction of hexafluorothioacetone dimer with azoles. Practical synthesis of N-(hexafluoro-iso-propyl)azoles

The reaction of azoles with 2,2,4,4-tetrakis-(trifluoromethyl)-1,3-dithietane led to the unexpected formation of N-(hexafluoro-isopropyl)azoles and sulfur, providing access to a group of compounds bearing a (CF3)2CH-group at nitrogen. Imidazole, pyrazole, 1,2,3- and 1,2,4-triazoles and benzo-derivatives of imidazole and triazole were found to undergo alkylation via reaction with 2,2,4,4-tetrakis-(trifluoromethyl)-1,3-dithietane, producing the corresponding derivatives in 54–83% yield.

ChemInform Abstract: Fused Heterocyclic Systems with s‐Triazine Ring. Part 21. Synthesis of Novel Trichloromethyl Substituted Azolo[1,3,5]triazines.

AbstractThe reaction of azoles (I) with trichloroacetonitrile (II) proceeds smoothly and regioselectively at the primary amino group of (I) to yield the trichloroacetamidines (III).

The reaction of azoles with 17-chloro-16-formylandrosta-5,16-dien-3β-yl-acetate: Synthesis and structural elucidation of novel 16-azolylmethylene-17-oxoandrostanes

The synthesis and structural elucidation, by 1D and 2D NMR and X-ray diffraction techniques, of novel E/ Z 16-azolylmethylene-17-oxoandrostanes 2– 9 prepared from the Vilsmeier–Hack reaction product 17-chloro-16-formylandrosta-5,16-dien-3β-yl acetate 1 is reported. The reaction proceeds with pyrrole and pyrrole-alike nitrogen heterocycles such as 7-azaindole, indole, and 3-methylindole, in DMF, at 80 °C, in the presence of K 2CO 3, and allowed the attachment of privileged heterocyclic moieties, through the nitrogen atom to the steroid core at C16 via a methine carbon bridge, which is unprecedented in the literature and of potential synthetic and biological interest. Considerations on the possible reaction mechanism are included. All the synthesized compounds are new and are currently being tested for biological activities.

ChemInform Abstract: Phase-Transfer Catalysis without Solvent. Synthesis of Bisazolylalkanes.

The reaction of azoles and benzazoles with dihalomethanes and dihaloethanes was performed in the absence of solvent. This method provides a general procedure for the synthesis of bisazolylmethanes and ethanes. No solvent was used during the reaction and, when possible, during the work-up

Copper-MediatedN-Cyclopropylation of Azoles, Amides, and Sulfonamides by Cyclopropylboronic Acid

Reaction of azoles, amides, and sulfonamides in dichloroethane with readily available cyclopropylboronic acid in the presence of copper acetate and sodium carbonate afforded the N-cyclopropyl derivatives in good to excellent yields.

N‐(2‐tetrahydrofuranyl)azole nucleoside analogs by reactions of azoles with dihalomethanes in tetrahydrofuran

AbstractThe reactions of the mono‐N‐substituted bispyrazolylpyridine 2‐(1‐methyl‐4,5,6,7‐tetxahydroindazol‐3‐yl)‐6‐(2H‐4,5,6,7‐tetrahydroindazol‐3‐yl)pyridine, 3,5‐dimethylpyrazole and benzimidazole with sodium hydride and diiodomethane or dibromomethane in tetrahydrofuran produced the unexpected N‐tetrahydrofuran‐2‐yl adducts as well as the expected diazolylmethanes. These side‐reactions are thought to involve the 2‐halo tetrahydrofuran derivative resulting from a free‐radical halogenation by the dihalomethane.

Phase Transfer Catalysis without Solvent. Synthesis of Bisazolylalkanes

The reaction of azoles and benzazoles with dihalomethanes and dihaloethanes was performed in the absence of solvent. This method provides a general procedure for the synthesis of bisazolylmethanes and ethanes. No solvent was used during the reaction and, when possible, during the work-up

Surface-Enhanced Raman Scattering (SERS) Study on the Air Oxidation of Copper and its Reactions with Azoles

Surface-Enhanced Raman Scattering (SERS) on HNO3-roughened copper foils has been used to follow the air oxidation of copper at room temperature and to study the surface reactions with azole compounds. It has been found that azoles react with metallic copper as well as copper oxides. SERS and IR studies show that the reaction of azoles with metallic copper is faster than with cuprous and cupric oxides.

Synthesis of 1-(α-Acyloxy-2-hydroxybenzyl)Azoles and Related Compounds by an Acyl Transfer Reaction

Novel azole adducts were produced by reaction of azoles and 2-acyloxyaryl aldehydes. The mechanism of the reaction involves attack by the azole at the carbonyl group and transfer of the acyl group to form an azole-substituted benzylic ester. 2-Acyloxyaryl ketones did not undergo an analogous reaction. An aminal was formed rather than an azole-substituted benzylic carbonate when a 2-aryl aldehyde carbonate was used as substrate.

ChemInform Abstract: Reaction of Azoles with Ethyl Bromopyruvate Oxime: Alkylation by Substitution and by Elimination‐Addition.

AbstractImidazole (I) reacts with the oxime (II) to give the monoalkylation product (III) and the zwitterion (IV).

Synthesis and antifungal properties of some N,N'-bis-azolylarylmethanes.

A series of 1, 1'-bis-azolylarylmethanes has been prepared by reaction of azoles and their benzoderivatives with ortho-, and para-chlorobenzaldehydes, thiophene-2-carbaldehyde and furan-2-carbaldehyde in the presence of zinc chloride as catalyst. The antifungal activity has been tested, in vitro, against Botrytis cinerea, Aspergillus flavus, Mucor rouxii and Candida albicans. All 1, 1'-bis-azolylarylmethanes have minima inhibitory concentrations (MIC) higher than that of chlotrimazol, used as positive control.

Reaction of azoles with ethyl bromopyruvate oxime: alkylation by substitution and by elimination–addition

Ethyl bromopyruvate oxime (1a) reacts with imidazole, 1-methylimidazole, pyrazole, 3-methylpyrazole, 3,5-dimethylpyrazole, and 1,2,4-triazole to give products of N-alkylation of the azoles. The rates of reaction of (1a) with imidazole, 1-methylimidazole, and 3,5-dimethylpyrazole are much faster than with the other azoles. The O-alkylated oxime (1b) reacts much more slowly than (1a) with imidazole and with 3,5-dimethylpyrazole. Imidazole is shown to be a strong enough base to eliminate HBr from the bromo oxime (1a), and the reaction of pyrazole with (1a) is greatly accelerated when an external base (sodium carbonate) is added. As a result, it is concluded that the more basic azoles, with pKa, values above 4, react with (1a) by an elimination–addition mechanism whereas the others react by direct displacement of bromide. Related reactions of imidazole and of 1,2,4-triazole with ethyl chloro(hydroxyimino)acetate have also been carried out and the N-substituted azoles (12), (13), and (14) have been isolated.

N‐polyazolylmethanes. 1. Synthesis and nmr study of N,N′‐diazolylmethanes

AbstractThirteen N,N‐diazolylmethanes, including derivatives of pyrazole, imidazole, 1,2,4‐triazole, benzimidazole and indazole were prepared by reaction of azoles with methylene chloride under phase transfer catalysis conditions. The relative amounts of isomeric mixtures obtained with ‘asymmetric’ azoles or with equimolar mixtures of azoles are compared with literature results on monoalkylation of azoles. Proton and carbon‐13 nmr spectra of the N,N'‐diazolylmethanes are discussed.

Reactions of azoles with isocyanates at elevated temperature

Reactions of azoles with isocyanates at elevated temperature