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1.
Convenient and facile one step synthesis of medicinally relevant new 3,6-epoxy[1,5]dioxocines from 2-hydroxyaromatic benzaldehydes is described. The scope of the method was validated by examining the use of both electron rich and electron-deficient 2-hydroxyaromatic benzaldehydes. 相似文献
2.
Three-component condensation of diethyl 2-oxobutanedioate sodium salt with aromatic aldehydes and tetrazol-5-amine monohydrate afforded the corresponding diethyl 6-aryl-3,6-dihydrotetrazolo[1,5-a]pyrimidine-4,5-dicarboxylates. 相似文献
3.
Maryna V. Murlykina Yana I. Sakhno Sergey M. Desenko Iryna S. Konovalova Oleg V. Shishkin Dmytro A. Sysoiev Maryna N. Kornet Valentin A. Chebanov 《Tetrahedron》2013
Three-component reactions of 5-aminopyrazoles and salicylic aldehydes with pyruvic acids were studied. The method of tuning of the selectivity of the heterocyclizations allowing to change its direction by variation of the reaction parameters was worked out. The treatment involving pyruvic acid can be selectively directed to the formation to either 3-aryl-10,11-dihydro-4,10-methano-pyrazolo[4,3-c][1,5]benzoxazocine-4-carboxylic acids or 3,6-diarylpyrazolo[3,4-b]pyridine-4-carboxylic acids, while the reaction involving arylpyruvic acid leads only to 7-hydroxy-2,5,6-triaryl-4,5,6,7-tetrahydro-pyrazolo[1,5-a]pyrimidine-7-carboxylic acids. Antimicrobial activity of the compounds obtained was also studied: Gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) were found sensitive to the substances tested, however, only in the highest concentration. 相似文献
4.
The reactions of β-lactam carbenes with both 3,6-di(2-pyridyl)tetrazine and 3,6-di(4-pyridyl)tetrazine were studied. It was found that β-lactam carbenes reacted with 3,6-di(2-pyridyl)tetrazine to produce 5-triazolo[1,5-a]pyridylpyrrol-2-ones in good yields, while with 3,6-di(4-pyridyl)tetrazine, they afforded pyrido[c]cyclopenta[b]pyrrol-2-ones in moderate yields. Both reactions were proposed to follow cascade mechanisms containing a 3,6a-dipyridylpyrrolo[3,2-c]pyrazol-5-one intermediate. The different pathways of the transformation of pyrrolo[3,2-c]pyrazol-5-ones were switched by the 2- and 4-pyridyl substituents. This work not only provided a simple and efficient strategy for the construction of novel triazolo[1,5-a]pyridine and pyrido[c]cyclopenta[b]pyrrole derivatives, respectively, but also revealed two different thermal transformation patterns of 3H-pyrazole compounds. 相似文献
5.
The reaction of the (S)-dimethylsulfonium-(p-tolylsulfinyl)methylide with aldehydes gave α,β-epoxy sulfoxides with high enantioselectivity and diastereoselectivity dependent on the aldehyde. The mechanism of the ‘model’ reactions [ylide substituted with Me S(O) or Ph S(O) with MeCHO or PhCHO] has been studied in detail using density functional theory. 相似文献
6.
《Chemical physics letters》1987,140(2):205-209
Aggregation of monomeric syn-bimanes (1,5-diazabicyclo [3.3.0] octa-3,6-dien-2,8-diones) via dimers or n-mers into crystallites (organized clusters) can be induced by appropriate solvents at 77 K and monitored by emission spectra and radiative rates. 相似文献
7.
Iodine-mediated cyclization of N-thioacyl 1,2-aminoalcohols derived from aromatic aldehydes and ketones mainly produced bis(1-imidazo[1,5-a]pyridyl)arylmethanes, whereas the reaction of N-thioacyl 1,2-aminoalcohols derived from aliphatic aldehydes and N-thioacyl 1,2-aminoalcohols protected with a silyl group with iodine gave imidazo[1,5-a]pyridine-1-ylalkylalcohols as a major product. 相似文献
8.
Mamdouh A. M. Taha Susan M. El-Badry 《Monatshefte für Chemie / Chemical Monthly》2008,73(5):1261-1267
Dehydrogenative cyclization of the 6-substituted 7-arylidenehydrazinotetrazolo[1,5-b][1,2,4]triazines derived from 6-methyl and 6-phenyl derivatives of 7-hydrazinotetrazolo[1,5-b][1,2,4]triazines and aromatic aldehydes gave the corresponding 6-substituted 9-aryl-[1,2,4]triazolo[4,3-d]tetrazolo-[1,5-b][1,2,4]triazines. The latter compounds were also obtained by an alternative route involving dehydrative cyclization of 6-methyl
and 6-phenyl derivatives of 7-chlorotetrazolo[1,5-b][1,2,4]triazines with aromatic hydrazides through the isolable aroylhydrazino intermediates. Also, the triazolotetrazolotriazine
rings were accomplished by one-pot cyclization of cyclic amidrazones with aromatic acid chlorides. The ditetrazolo[1,5-b:1′,5′-d][1,2,4]triazine systems were synthesized by cyclization of the former cyclic amidrazones with nitrous acid, or cyclic imidoyl
chlorides with sodium azide. The bis-triazolotetrazolotriazine derivatives were synthesized by cyclization of two equivalents
of each cyclic imidoyl chloride with acid dihydrazides through the isolable bis-hydrazide products. The antimicrobial activity
of representative compounds was studied. 相似文献
9.
Daniil N. Lyapustin Evgeny N. Ulomsky Ilya A. Balyakin Alexander V. Shchepochkin Vladimir L. Rusinov Oleg N. Chupakhin 《Molecules (Basel, Switzerland)》2021,26(16)
The reaction tolerance of the multicomponent process between 3-aminoazoles, 1-morpholino-2-nitroalkenes, and aldehydes was studied. The main patterns of this reaction have been established. Conditions for the oxidation of 4,7-dihydro-6-nitroazolo[1,5-a]pyrimidines were selected. Previous claims that the 4,7-dihydro-6-nitroazolo[1,5-a]pyrimidines could not be aromatised have now been refuted. Compounds with an electron-donor substituent at position seven undergo decomposition during oxidation. The phenomenon was explained based on experimental data, electro-chemical experiment, and quantum-chemical calculation. The mechanism of oxidative degradation has been proposed. 相似文献
10.
Mamdouh A. M. Taha Susan M. El-Badry 《Monatshefte für Chemie / Chemical Monthly》2008,139(10):1261-1267
Dehydrogenative cyclization of the 6-substituted 7-arylidenehydrazinotetrazolo[1,5-b][1,2,4]triazines derived from 6-methyl and 6-phenyl derivatives of 7-hydrazinotetrazolo[1,5-b][1,2,4]triazines and aromatic aldehydes gave the corresponding 6-substituted 9-aryl-[1,2,4]triazolo[4,3-d]tetrazolo-[1,5-b][1,2,4]triazines. The latter compounds were also obtained by an alternative route involving dehydrative cyclization of 6-methyl
and 6-phenyl derivatives of 7-chlorotetrazolo[1,5-b][1,2,4]triazines with aromatic hydrazides through the isolable aroylhydrazino intermediates. Also, the triazolotetrazolotriazine
rings were accomplished by one-pot cyclization of cyclic amidrazones with aromatic acid chlorides. The ditetrazolo[1,5-b:1′,5′-d][1,2,4]triazine systems were synthesized by cyclization of the former cyclic amidrazones with nitrous acid, or cyclic imidoyl
chlorides with sodium azide. The bis-triazolotetrazolotriazine derivatives were synthesized by cyclization of two equivalents
of each cyclic imidoyl chloride with acid dihydrazides through the isolable bis-hydrazide products. The antimicrobial activity
of representative compounds was studied.
Correspondence: Mamdouh A. M. Taha, Chemistry Department, Faculty of Science, Faiyoum University, Faiyoum 63514, Egypt. 相似文献
11.
3-(-haloacyl)-2,4-dialkylpyrazolo[1,5-a]benzimidazoles can be obtained either by brominating 3-acetylpyrazolo[1,5-a]benzimidazoles with bromine in acetic acid, or by acylating the 3-unsubstituted pyrazolobenzimidazoles with haloacetic halides. Halogenation of 3-acetylpyrazolo[1,5-a]benzimidazoles with bromine in acetic acid in the presence of sodium acetate, and bromination with N-bromosuccinimide or 1-chlorobenzotriazole, result in deacylation to give 3,6(7)-dibromo- and 3-chloropyrazolo[1,5-a]benzimidazoles. The mono- and trihaloketones obtained have been used to prepare the corresponding aminoketones, the 3-carboxylic acid, and its derivatives.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 43–48, January, 1988. 相似文献
12.
[reaction: see text] Reaction of various aromatic aldehydes with 2,2'-dipyridyl ketone and ammonium acetate in hot acetic acid provides ready access to a series of substituted 1-pyridylimidazo[1,5-a]pyridines, a class of ligands possessing an N,N-bidentate feature, in good yields. 相似文献
13.
Mohamed I. Ali Abou El-fotooh G. Hamman Salwa F. Mohamed 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):211-216
Abstract 1,2,3,4-Tetrahydro-l-aryl-3,9-dioxo-2,4-diazafluorenes (2) and 1,2,3,4-tetrahydro-1-aryl-9-oxo-3-thi-oxo-2,4-diazafluorenes (3) were newly synthesized. Compounds 3 reacted with chloroacetic acid, α-bromopropanoic acid, or B-bromopropanoic acid in the presence of fused sodium acetate and acetic anhydride to give 2,3-dihydro-5-aryl-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (4), 2-methyl-2,3-dihydro-5-aryl-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (5) and 2,3-dihydro-6-aryl-6H,7H-thiazino[3,2-b]2,4-diazafluorene-4,7-diones (6), respectively. 2,3-Dihydro-2-arylmethylene-5-aryl-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (7) were prepared by the reaction of compounds (3) with chloroacetic acid and aromatic aldehydes in the presence of fused sodium acetate and acetic anhydride or by the reactions of (4) with aromatic aldehydes in the presence of acetic anhydride. 2-(Arylhydroazono)-5-aryl-2,3-dihydro-5H,6H-thiazolo[3,2-b]2,4-diazafluorene-3,6-diones (8) were synthesized by coupling (4) with aryldiazonium salts in the presence of pyridine. 相似文献
14.
Yasuyoshi Miki Sanae Yagi Hiroko Hachiken Masazumi Ikeda 《Journal of heterocyclic chemistry》1993,30(4):1045-1046
Reaction of pyrazolo[1,5-a]pyridines with aldehydes in the presence of trifluoroacetic acid gave bis[pyrazolo[1,5-a]pyrid-3-yl)methanes in high yields. 相似文献
15.
The synthesis of 3,6-epoxy carotenoids cucurbitaxanthin A 1, cycloviolaxanthin 2 and capsanthin 3,6-epoxide 3, was accomplished via the C(15)-3,6-epoxides 20e and 20f, prepared by the regioselective ring opening of the 3-hydroxy-5,6-epoxides 10e and 10f. 相似文献
16.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(13):3629-3632
This study presents the synthesis and characterization of the oxidation products of 3,6‐diazido‐1,2,4,5‐tetrazine ( 1 ) and 6‐amino‐[1,5‐b ]tetrazolo‐1,2,4,5‐tetrazine ( 2 ). 3,6‐Diazido‐1,2,4,5‐tetrazine‐1,4‐dioxide was produced from oxidation with peroxytrifluoroacetic acid, and more effectively using hypofluorous acid, and 2 can be oxidized to two different products, 6‐amino‐[1,5‐b]tetrazolo‐1,2,4,5‐tetrazine mono‐N‐oxide and di‐N‐oxide. These N‐oxide compounds display promising performance properties as energetic materials. 相似文献
17.
18.
Axel Sczostak Frank Sönnichsen Werner Tochtermann Eva-Maria Peters Karl Peters Hans Georg von Schnering 《Tetrahedron letters》1985,26(46):5677-5680
Irradiation of the 3,6-hexanooxepins 1a – 1c affords the tricyclo[6.2.1.01,5] undec-9-ene(3a,6-methanooctahydroazulene)derivatives 2a – 2c in about 50% yield. 相似文献
19.
Lai Bao Wang Jia Pan Can Ling Tang Xiu Ren Bu Jie Wang 《中国化学快报》2007,18(4):390-392
Under regular heating and microwave irradiation, 3-alkyl substituted imidazo[1,5-a] pyridines were synthesized from 2,2'- pyridil, di-2-pyridyl ketone and aliphatic aldehydes in the presence of ammonium acetate and acetic acid. Compared to the traditional heating condition, the reaction time under microwave irradiation was shorter and 3-alkyl imidazo[1,5-a]pyddines were given in higher yield. 相似文献
20.
A Pd-catalyzed cross-coupling reaction of α-alkoxytosylhydrazones with sulfonates derived from salicyl aldehydes gives rise to protected 1,5-dicarbonyl compounds. Treatment with ammonium hydroxide readily transforms these alkenes into isoquinolines with diverse substitution patterns at positions 3 and 4. In a similar way, the employment of o-cyanononaflates in the coupling reaction, followed by treatment with an organometallic, provides isoquinolines that incorporate substitution also at position 1. The combination of both approaches represents a versatile method for the preparation of isoquinolines substituted at any position of the heterocyclic ring. 相似文献