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1.
A systematic exploration of thiophilic ability of o-iodoxybenzoic acid (IBX) for oxidative desulfurization to trigger domino reactions leading to new methodologies for synthesis of different azoles is described. A variety of highly substituted oxadiazoles, thiadiazoles, triazoles, and tetrazoles have been successfully synthesized in good to excellent yields, starting from readily accessible thiosemicarbazides, bis-diarylthiourea, 1,3-disubtituted thiourea, and thioamides. 相似文献
2.
R. Lee Webb Drake S. Eggleston Clifford S. Labaw Joseph J. Lewis K. Wert 《Journal of heterocyclic chemistry》1987,24(1):275-278
Simple high yield methods for the preparation of heterocyclic N-cyanoguanidines (including the anti-ulcer drug cimetidine), substituted triazoles, benzimidazoles and oxadiazoles with anti-histaminic (H2) activity from the title compounds are described. 相似文献
3.
Barbara Milczarska Katarzyna Gobis Henryk Foks Lukasz Golunski Pawel Sowinski 《Journal of heterocyclic chemistry》2012,49(4):845-850
In research of new biologically active compounds, the reactions of amino‐pyrazin‐2‐hydrazide and methylhydrazide with isothiocyanates, aromatic aldehydes, ketones, CS2, and formic acid were made. New thiosemicarbazides, 1,3,4‐thiadiazoles, 1,3,4‐oxadiazoles, and 1,2,4‐triazoles were obtained. New 4‐oxopteridine derivative 26 was also synthesized. 相似文献
4.
《Journal of heterocyclic chemistry》2017,54(2):1355-1360
A series of novel 1,3,4‐thiadiazoles, 1,2,4‐triazoles, and 1,3,4‐oxadiazoles were synthesized by cyclization of substituted 1‐(2‐(2‐chlorophenyl)‐2‐(4‐(2,3‐dichlorophenyl)piperazin‐1‐yl)acetyl)thiosemicarbazide. The structures of all newly synthesized compounds were elucidated on the basis of spectral studies. Some of them were screened for their antibacterial activity. The compounds 6b , 6c , 8e , 9a , and 9b have shown moderate activity towards Bacillus Subtilis and Escherichia Coli . 相似文献
5.
Venkatapuram Padmavathi Pinnu Thriveni Boggu Jagan Mohan Reddy Adivireddy Padmaja 《Journal of heterocyclic chemistry》2005,42(1):113-116
A new class of five membered heterocycles, thiadiazoles, triazoles and oxadiazoles were prepared from sulfonyl acetic acids via acid hydrazides. 相似文献
6.
A new series of 1,3,4‐oxadiazoles, 1,2,4‐triazoles, 1,3,4‐thiadiazoles were synthesized using alkylhydrazides as the starting materials, and then 1,2,4‐triazoles were used to synthesize [1,2,4]triazolo[3,4‐b][1,3,4]thiadiazoles. All the compounds were evaluated for in vitro antibacterial activity and antitumor activity. 相似文献
7.
A number of 4-allylic substituted 3,5-diphenyl-4H-1,2,4-triazoles were thermolyzed at 315–320° in evacuated glass ampoules. The main reaction in the melt was rearrangement to the corresponding 1-substituted triazoles, which appeared to proceed via competing SN2 and SN2′ mechanisms. The allylic systems were observed to undergo [2,3]-allyl walk reactions between the 1- and 2-ring positions. Allyl to vinyl isomerization also took place. Substitution of the allylic moiety increased the rate of reaction but decreased the rate of isomerization of allylic to the vinylic substituted triazoles. The 4-vinyl substituted triazoles were inert under the reaction conditions. Some triazoles were converted into substituted pyridines. This was proposed to proceed via nitrogen extrusion and formation of a 1,3-dipolar intermediate (nitrile ylide) which added intramolecularly to the allyl moiety and subsequently aromatized to the pyridine. 相似文献
8.
Synthesis of a New Class of Sulfonamido Bis Heterocycles—Pyrrolyl/Pyrazolyl‐1,3,4‐oxadiazoles, 1,3,4‐Thiadiazoles,and 1,2,4‐Triazoles 下载免费PDF全文
Akkarapalli Muralikrishna Guda Mallikarjuna Reddy Gopala Lavanya Venkatapuram Padmavathi Adivireddy Padmaja 《Journal of heterocyclic chemistry》2014,51(1):179-190
A new class of sulfonamido bis heterocycles—pyrrolyl/pyrazolyl‐oxadiazoles, thiadiazoles, and triazoles—were prepared from arylaminosulfonylacetic acid hydrazide and E‐aroylethenesulfonylacetic acid adopting simple and versatile synthetic methodologies. 相似文献
9.
Vinyl-substituted oxadiazoles and triazoles were prepared through hydrazinolysis, acylation, cyclocondensation, and elimination of selenium resins. The polystyrene-supported resins used here not only facilitate separation of products but also serve as a pro-vinyl safety-catch linker. 相似文献
10.
Dr. Fei Ma Dr. Jie Li Shuning Zhang Yuang Gu Tingting Tan Wanting Chen Shuyue Wang Dr. Peixiang Ma Dr. Hongtao Xu Prof. Guang Yang Prof. Richard A. Lerner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(31):8214-8220
DNA-encoded combinatorial chemical library (DEL) technology, an approach that combines the power of genetics and chemistry, has emerged as an invaluable tool in drug discovery. Skeletal diversity plays a fundamental importance in DEL applications, and relies heavily on novel DNA-compatible chemical reactions. We report herein a phylogenic chemical transformation strategy using DNA-conjugated benzoyl hydrazine as a common versatile precursor in azole chemical expansion of DELs. DNA-compatible reactions deriving from the common benzoyl hydrazine precursor showed excellent functional group tolerance with exceptional efficiency in the synthesis of various azoles, including oxadiazoles, thiadiazoles, and triazoles, under mild reaction conditions. The phylogenic chemical transformation strategy provides DELs a facile way to expand into various unique chemical spaces with privileged scaffolds and pharmacophores. 相似文献
11.
This review article discusses the reaction of nitrilimines and nitrile oxides with hydrazines, hydrazones, and oximes. Three reaction modes were observed. The article mainly covers our work published over the last fifteen years, in which interesting heterocyles such as oxadiazoles, triazoles, and tetrazines were synthesized and fully characterized. 相似文献
12.
Sultan T. Abu-Orabi M. Adnan Atfah Ibrahim Jibril Fakhri M. Mari'i Amer Al-Sheikh Ali 《Journal of heterocyclic chemistry》1989,26(5):1461-1468
Phenyl azide 1 and several substituted benzyl azides 2a-o underwent 1,3-dipolar cycloaddition reactions with dimethyl acetylenedicarboxylate 3, phenylacetylene 4 and ethyl propiolate 5 to afford the triazoles 6-13. The reactions of these azides with ethyl propiolate were found to be completely regiospecific. 相似文献
13.
Dong Han Xiang-Bao Meng Lin-Na Wang Hong Liu Yun Yao Zhuo Wang Zhen-Jun Yang Zhen-Min Liu Zhong-Jun Li 《Tetrahedron: Asymmetry》2009,20(4):399-410
A series of novel alkyl substituted fructose-based oxadiazoles were synthesized and their cytotoxic activities toward tumor cells were investigated. We studied the reaction mechanism and the stereochemistry of the reaction. Tautomerization between isomers 2 and 3 was observed in solution. The tautomerization was accelerated by heating or in the presence of acetic acid. An intermediate 6 during the heterocyclization was isolated, and two different pathways for the heterocyclization were suggested. On the basis of these findings, an efficient method, with the assistance of microwave irradiation was developed for the synthesis of 4 and 5. The yields were satisfactory and no by-products were found. We also proposed that the (R/S)-configurations of oxadiazoles were determined by the E/Z configurations of hydrazones. 相似文献
14.
A systematic review is given for advances in the synthesis of various azoles (imidazoles, oxazoles, thiazoles, pyrazoles, oxadiazoles, and triazoles) containing indole fragments. A significant number of biologically active compounds have been found among these bisheterocyclic compounds.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 147–172, February, 1986. 相似文献
15.
16.
含吡唑环的双杂环化合物的合成及其生物活性 总被引:14,自引:0,他引:14
以4-硝基-5-吡唑甲酰肼为起始物,合成了一系列含硝基的5-吡唑基-1,3,4-噁二唑类、5-吡唑基-1,3,4-噻二唑类和5-吡唑基-1,3,4-三唑类的化合物.初步生测结果表明:部分化合物有较好的杀菌和内吸活性. 相似文献
17.
Easy access to triazoles, triazolopyrimidines, benzimidazoles and imidazoles from imidates 总被引:1,自引:0,他引:1
We have described a new and easy synthesis of triazoles, triazolopyrimidines, benzimidazoles and imidazoles variously substituted based on the reaction of imidates with diamine derivatives. The products were obtained in moderate to good yields. A general mechanism for the reactions is proposed. 相似文献
18.
Alfons Dorlars Carl-Wolfgang Schellhammer Joseph Schroeder 《Angewandte Chemie (International ed. in English)》1975,14(10):665-679
Optical brighteners are used in detergents, textiles, paper, plastics, and paints. Most optical brighteners contain heterocycles such as coumarins, 2-pyrazolines, naphthalimides, pyrazoles, triazoles, oxadiazoles, and triazines. In this article the syntheses, properties, and applications of new optical brighteners are described with references to patent literature. 相似文献
19.
V. Ya. Alekseeva Yu. A. Boitkov I. V. Viktorovskii K. A. V'yunov 《Chemistry of Heterocyclic Compounds》1986,22(11):1258-1261
2-Amino-5-R-phenyl-1,3,4-oxadiazoles have been shown to isomerize in alcoholic potassium hydroxide solution to 3-R-phenyl-5-alkoxy-1,2,4-triazoles. The dissociative ionization of 3-R-phenyl-5-alkoxy-1,2,4-triazoles and 3-R-phenyl-1,2,4-triazolin-5-ones has been examined. The mass spectra of the oxadiazoles have been compared with those of the triazoles.Translated from Khimiya Geterotslklicheskikh Soedinenii, No. 11, pp. 1553–1556, November, 1986. 相似文献
20.
《Journal of heterocyclic chemistry》2018,55(9):2142-2150
A new class of 2,6‐pyridine linked bis (oxadiazoles), bis (thiadiazoles), and bis (triazoles) were prepared from the synthetic intermediates pyridine‐2,6‐dicarbohydrazide, E‐aroylethenesulfonylacetic acid and E‐arylsulfonylethenesulfonylacetic acid adopting ultrasonication methodology and tested for their antioxidant activity. Among all the tested compounds 2,6‐(bis (2‐(4‐methylbenzoylethenesulfonylmethyl)‐1,3,4‐oxadiazol‐5‐yl))‐pyridine ( 7b ) was found to be potential antioxidant agent. 相似文献