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The reaction of 4-chloro-2-methylquinolines and 1-naphthylamine under neat conditions yielded 2-methyl-N-(1-naphthyl)quinolin-4-amines. These potential intermediates on reaction with aliphatic and aromatic carboxylic acids yielded the respective 7-alkyl and -aryl substituted benzo[h]naphtho[1,2-b][1,6]naphthyridines. The highly deshielded protons in the final compounds were assigned on the basis of 2D NMR studies. 相似文献
3.
I. Strakova M. Petrova S. Belyakov A. Strakovs 《Chemistry of Heterocyclic Compounds》2003,39(12):1608-1616
The interaction of 3-formyl-4-coumarin with arylhydrazine hydrochlorides in the presence of sodium acetate gave the corresponding 3-arylhydrazonomethyl-4-chlorocoumarin, and with phenylhydrazine, 4-bromo- and 4-chlorophenylhydrazine hydrochlorides in the presence of two equivalents of triethylamine gave either 1-aryl- or 2-aryl[1]benzopyrano[4,3-c]pyrazol-4-ones depending on the reaction conditions. In reactions of 4-chloro-3-formylcoumarin with 2,4-dichloro-, 2,4-difluoro-, 2-hydroycarbonyl-, 4-nitro- and 3,5-di(trifluoromethyl)phenylhydrazine, 2-pyridyl- and 2-quinoxalylhydrazine in the presence of excess of triethylamine the 2-aryl[1]benzopyrano[4,3-c]pyrazol-4(2H)-ones were obtained exclusively. The structures of 1-phenyl- and 2-(2-pyridyl)[1]benzopyrano[4,3-c]pyrazolo-4(1H)ones were confirmed by X-ray crystallography. A simple method is proposed to distinguish between 1- and 2-substituted [1]benzopyrano[4,3-c]pyrazolo-4-ones on the basis of the 1H NMR chemical shifts of the C(3)-H proton in two solvents - DMSO-d6 and CDCl3. 相似文献
4.
An efficient method has been developed for the synthesis of 2-[3(5)-aryl(methyl)pyrazol-4-yl]-1H-benzimidazoles by cyclocondensation
of 2-acylmethyl-1H-benzimidazoles benzoylhydrazones with DMF dimethylacetal. The tautomerism of the compounds obtained via
migrations of a proton between the pyrazole nitrogen atoms has been studied by 1H NMR. The more stable tautomers have electron acceptor aryl substituents placed at position 3 of the pyrazole ring and electron
donor aryl substituents or a methyl at position 5.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1370–1377, September, 2006. 相似文献
5.
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
6.
Divyaraj Puthran Boja Poojary Soukhyarani G. Nayak Nikil Purushotham Manjunath Bhat Hemant Hedge 《中国化学会会志》2020,67(7):1278-1288
2-amino-5-(3-fluoro-4-methoxyphenyl)thiophene-3-carbonitrile derivatives have been synthesized from 1-(3-fluoro-4-methoxyphenyl)ethanone, malononitrile, mild base, and sulfur powder using the Gewald method through a multistep reaction sequence. The structures of newly synthesized compounds were established on the basis of their elemental analyses, IR, 1H NMR, 13C NMR, and mass spectral data, and then synthesized compounds were screened for their in vitro antimicrobial activity. Among them, derivatives 3b (thiphene), 3f (pyrazole), and 3d (halogen) showed good activity and remaining derivatives exhibited moderate activity. 相似文献
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Synthesis of novel herbicidal sulfonylureas 总被引:1,自引:0,他引:1
Novel sulfonylurea derivatives containing flve-membered hete-rocycle 3a-1 and 4a-d were synthesized in good yields by the regioselective addition of aryl sulfonylisocyanates 1 to 5-amino-3-benzyl (aryl) thio-1, 2, 4-triazoles and its pyrazole analogues 2. The structures of all these compounds were evaluated by elemental analyses and 1H NMR spectroscopy. The preliminary biological tests showed that the products displayed herbiddal activity against rape to some extent. 相似文献
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1-苯基-3-甲基-5-氯-4-吡唑甲醛与4-氨基-5-取代苯基-1,2,4-三唑-3-硫酮缩合生成4-(1-苯基-3-甲基-5-氯吡唑次甲亚胺基)-5-(取代苯基)-2H-1,2,4-三唑-3(4H)-硫酮,再烷基加成化为新型含吡唑基5,6-2H-1,2,4-三唑[3,4-b][1,3,4]噻二嗪衍生物。 化合物结构经1H NMR、IR以及元素分析确认。 初步生物活性测试结果表明,在100 mg/L浓度下,化合物8a(3-(2-甲基苯基)-6-(5-氯-2-甲基-4-苯基吡唑)-7-(4-硝基苯基)-5H-1,2,4-三唑[3,4-b][1,3,4]噻二嗪)对黄瓜炭疽病的抑制率达90%。 相似文献
9.
N-Methylation at the pyrazole ring by sequential treatment of 5-tributylstannyl-4-trifluoromethylpyrazole with LDA and iodomethane regioselectively provided the title compound in high yield. The addition reaction of 5-lithiated-4-trifluoromethylpyrazole with a wide range of electrophiles allowed easy and high-yielding introduction of substituents on position 5. 相似文献
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Ze-Hun Cao Yu-Hao Wang Dr. Subarna Jyoti Kalita Dr. Uwe Schneider Prof. Dr. Yi-Yong Huang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(5):1900-1906
Unprecedented phosphine-catalyzed [4+1] cycloadditions of allenyl imides have been discovered using various N-based substrates including methyl ketimines, enamines, and a primary amine. These transformations provide a one-pot access to cyclopentenoyl enamines and imines, or (chiral) γ-lactams through two geminal C−C bond or two C−N bond formations, respectively. Several P-based key intermediates including a 1,4-(bis)electrophilic α,β-unsaturated ketenyl phosphonium species have been detected by 31P NMR and HRMS analyses, which shed light on the postulated catalytic cycle. The synthetic utility of this new chemistry has been demonstrated through a gram-scaling up of the catalytic reaction as well as regioselective hydrogenation and double condensation to form cyclopentanoyl enamines and fused pyrazole building blocks, respectively. 相似文献
12.
ZOU Jian-Ping LU Zhong-E CHEN Ke-QianDepartment of chemistry Suzhou University Suzhou Jiangsu China 《中国化学》1995,13(4):358-362
Fourteen new 1-acyl-5-aryl biurets were synthesized by the reaction of aryl ureas with acylisocynantes. The latter was obtained from acyl chloride and lead cyanate in dichloromethane, using pyridine as catalyst. The structures of compounds 3a-n were confirmed by IR,1H NMR and MS spectra. 相似文献
13.
Mehdi Adib Moharram Omidi Hamid Reza Bijanzadeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1732-1738
Crystalline phosphorus ylides are obtained in nearly quantitative yields from the 1:1:1 addition reaction between triphenylphosphine, dialkyl acetylenedicarboxylates, and 4-aryl urazoles. 相似文献
14.
采用乙酸作溶剂和催化剂, 将芳乙酮与甲醛和二级胺进行Mannich反应及热解反应, 并未得到预期的Mannich碱或α,β-不饱和酮(2), 而是以较高产率(65%~73%)生成了乙酸(2-芳甲酰基)烯丙酯(3a~3o). 通过核磁共振波谱、 高分辨质谱和红外光谱表征了化合物3a~3o的结构, 研究了此“异常”反应的发生条件, 并提出了可能的反应机理. 结果表明, 芳乙酮的特殊结构及反应中过量的乙酸是产生化合物3a~3o的决定因素. 相似文献
15.
Ze‐Hun Cao Yu‐Hao Wang Subarna Jyoti Kalita Uwe Schneider Yi‐Yong Huang 《Angewandte Chemie (International ed. in English)》2020,59(5):1884-1890
Unprecedented phosphine‐catalyzed [4+1] cycloadditions of allenyl imides have been discovered using various N‐based substrates including methyl ketimines, enamines, and a primary amine. These transformations provide a one‐pot access to cyclopentenoyl enamines and imines, or (chiral) γ‐lactams through two geminal C?C bond or two C?N bond formations, respectively. Several P‐based key intermediates including a 1,4‐(bis)electrophilic α,β‐unsaturated ketenyl phosphonium species have been detected by 31P NMR and HRMS analyses, which shed light on the postulated catalytic cycle. The synthetic utility of this new chemistry has been demonstrated through a gram‐scaling up of the catalytic reaction as well as regioselective hydrogenation and double condensation to form cyclopentanoyl enamines and fused pyrazole building blocks, respectively. 相似文献
16.
Jennifer E. Golden Shanina D. Sanders Kristine M. Muller Roland W. Bürli 《Tetrahedron letters》2008,49(5):794-798
The regioselective, copper-catalyzed coupling of a tautomeric pyrazolone/pyrazole with 2-halopyridines was investigated. Conditions were developed to preferentially form either the N-aryl or O-aryl product. 相似文献
17.
The superelectrophilic activation of N-aryl amides of 3-arylpropynoic acids by Bronsted superacids (CF3SO3H, HSO3F) or strong Lewis acids AlX3 (X=Cl, Br) results in the formation of 4-aryl quinolin-2(1H)-ones in quantitative yields. The vinyl triflates or vinyl chlorides may be formed as additional reaction products. The investigated amides in reactions with benzene give 4,4-diaryl 3,4-dihydroquinolin-2-(1H)-ones under the superelectrophilic activation. 4-Aryl quinolin-2(1H)-ones in POCl3 are converted into 4-aryl 2-chloroquinolines. 4-Fluorophenyl-4-phenyl 3,4-dihydroquinolin-2-(1H)-one give N-formylation products in a yield of 79% under the Vilsmeier–Haack reaction conditions. 相似文献
18.
LU Rong-Jian QIAN Bao-Ying DENG Hai-Yan YANG Hua-ZhengNational Key Laboratory of Elemento-Organic Chemistry Institute of Elemento-Organic Chemistry Nankai University Tianjin China 《中国化学》1997,(6)
The orientation of the addition of 5-amino-3-benzylthio-1,2,4-triazole and its analogues (pyrazole) (1) with the aryl isocyanate can be directed by controlling the reaction temperature and one of the product, 5-amino-1-arylaminocarbonyl-3-benzylthio-1,2,4-triazole (pyrazole) (2), can rearrange at 170C to another product, 5-arylureylene-3-benzylthio-1,2,4-triazole (pyrazole) (3). A plausible mechanism explanation for this rearrangement reaction was presented. It was suggested that the rearrangement reaction could be referred to the thermodynamics transposition leading to the predominant 5-arylureylene-3-benzylthio-1,2,4-triazole energy preferentially. 相似文献
19.
A. T. Soldatenkov T. P. Khristoforova A. W. Temesgen B. N. Anissimov B. B Averkiev L. N. Kuleshova V. N. Khrustalev M. Yu. Antipin 《Chemistry of Heterocyclic Compounds》2001,37(6):715-722
On treating 4-aryl substituted 1-methyl-1,2,3,6-tetrahydropyridines with potassium permanganate in the presence of arylamines a previously unknown intermolecular oxidative imination reaction occurs leading to the formation of 2-(arylimino)-1,2,5,6-tetrahydropyridines. The molecular structure of 1-methyl-2-(4-nitrophenylimino)-4-phenyl-1,2,5,6-tetrahydropyridine was studied by X-ray analysis and it was shown that the hydropyridine ring of the molecule has a sofa conformation and its amidine fragment is in the E-configuration. 相似文献
20.
Tai CL Hung MS Pawar VD Tseng SL Song JS Hsieh WP Chiu HH Wu HC Hsieh MT Kuo CW Hsieh CC Tsao JP Chao YS Shia KS 《Organic & biomolecular chemistry》2008,6(3):447-450
A novel class of (5-(pent-1-enyl)thiophen-2-yl)pyrazole antagonists was discovered, many of which exhibited potent CB1 activity and good CB1/2 selectivity, suggesting that along with a 1,3-transposition of the carbonyl of the pyrazole 3-carboxamide, bioisosteric replacement of the conventional pyrazole 5-aryl group with a thienyl ring substituted with an appropriate alkenyl moiety is viable. 相似文献