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1.
Bicyclic azulene compounds, ethyl 4-(cyanoethoxycarbonylmethyl)-2-methylazulene-1-carboxylate (2) and ethyl 4-(cyanoethoxycarbonylmethyl)azulene-1-carboxylate (3) were prepared from ethyl 4-chloro-2-methylazulene-1-carboxylate (7) and ethyl 4-ethoxyazulene-1-carboxylate (8), respectively. Oxidation of 2 with DDQ gave the title compound, 5-cyano-4-ethoxy-1-ethoxycarbonyl-2-methylazuleno[1,8-b,c]pyran (1) and a minor compound, ethyl 4-cyanomethyl-2-methylazulene-1-carboxylate (9). Oxidation of 3 by DDQ produced only ethyl 4-cyanomethylazulene-1-carboxylate (10), Reaction of 1 with 100% H3PO4 at room temperature and 100 °C gave 5-cyano-4-ethoxy-2-methylazuleno[1,8-b,c]pyran (11) and 2-methyl-4,5-dihydrozuleno[1,8-b,c]pyran-4-one (12), respectively. All the new compounds were characterized by IR, UV-vis, NMR and Mass spectra, and the structure of 1 was determined by X-ray crystallography. Crystal data for 1; space group P21/n, a = 7.391(1), b = 9.660(5), c = 22.859(1) Å, B = 97.01(1)°, V = 1620.0(3) Å3, Z = 4, with final residuals R = 0.047 and Rw = 0.055. 相似文献
2.
E. Gössinger M. Graupe K. Zimmermann 《Monatshefte für Chemie / Chemical Monthly》1994,125(6-7):773-782
Summary The diketone3 was reduced to the diol which then was transformed to the tetracyclic diketal5 by treatment with sodium in ethanol. Protection of the remaining hydroxy group was followed by hydrolysis of the dimethylketal. The resulting ketone7 was stereoselectively converted to the tertiary alcohol by methyl magnesium chloride. Acidic retrograde aldol reaction of the tertiary alcohol led to the decalindione10, which was partially dehydrogenated by cupric chloride under basic conditions. The resulting endione1 cyclized by light induced hydrogen abstraction and collapse of the resulting diradical to the perhydronaphtho[1,8-bc]furan derivative. 相似文献
3.
A. Sirisha Madhuritha B. Ashok Kumar T. Parthasarathy V. Uma 《Central European Journal of Chemistry》2004,2(4):696-702
A quantitative structure activity relationship (QSAR) study of 2-substituted 2,3-dihydro-1H-naphtho[1,8,de]-1,3,2-diazaphosphorine
2-oxides and sulphides (DND), examines the extent of the contribution by various physicochemical parameters with respect to
their antimicrobial activity. Simple bivariant regression analysis, based on the least squares method, is applied in order
to predict models. The predicted models reveal that the steric factor, MR, is the major contributor influencing antimicrobial
activity. Bulky groups at the C-19 (C=0 group) position positively influence the potency of the compounds 相似文献
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7.
Said M. Bayomi 《中国化学会会志》1992,39(1):101-104
A convenient route is reported for the synthesis of fused pyrrolo[2,3-d][1,3]oxazine and pyrrolo[2,3-d]-pyrimidine derivatives from 2-amino-1-benzyl-3-t-butoxycarbonyl]-4,5-dimethylpyrrole. 相似文献
8.
Adolfo Sánchez Luisa Quijano Manuel Melguizo Manuel Nogueras 《Monatshefte für Chemie / Chemical Monthly》1989,120(12):1119-1124
Summary Three series of 3-substituted 5-glycopyranosylamino pyrano[2,3-d]pyrimidin-2-one derivatives,3 a–c,4 a–c, and5 a–c have been prepared by treatment of the corresponding 1,4-dihydro-6-glycopyranosylamino pyrimidin-4-ones1 a–c with malonic, methyl malonic and ethyl malonic acids, respectively.
Synthese von Derivaten des 5-Glucopyranosylaminopyrano[2,3-d]pyrimidin-2-on
Zusammenfassung Es wurden drei Serien von 3-substituierten 5-Glucopyranosylaminopyrano[2,3-d]pyrimidin-2-onen (3 a–c,4 a–c und5 a–c) mittels Behandlung der entsprechenden 1,4-Dihydro-6-glucopyranosylamino-pyrimidin-4-one (1 a–c) mit Malon-, Methylmalon- bzw. Ethylmalonsäure dargestellt.相似文献
9.
We have established that when 5-chloro-6-[cyano(2,3-dihydro-1-R-benzo[d]azol-2-yl)methyl]-2,3-pyrazinedicarbonitriles are reacted with nucleophilic reagents (aliphatic and aromatic amines, hydrogen sulfide), annelation of the five-membered ring occurs on the [b] face of the pyrazine with formation of 6-amino-7-hetaryl-5-R-5H-pyrrolo[2,3-b]pyrazine-2,3-dicarbonitriles and 6-amino-7-(1H-benzo[d]imidazol-2-yl)thieno[2,3-b]pyrazine-2,3-dicarbonitrile respectively. Further heating with excess of acylating reagent leads to formation of a novel heterocyclic system 1H-benzo[4,5]imidazo[1,2-c]pyrazino[2',3':4,5]pyrrolo[3,2-e]pyrimidine. Reaction of vicinal dinitriles with hydrazine hydrate leads to the novel system 1H-pyrrolo[2',3':5,6]pyrazino[2,3-d]pyridazine. 相似文献
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11.
Jeffrey T. Kuethe 《Tetrahedron》2019,75(34):130446
A strategy for the efficient and rapid one-pot synthesis of 2-aryl-2,3-dihydrofuro[3,2-b], [3,2-c], and [2,3-b]pyridines from readily available o-nitropicolines and aromatic aldehydes is described. The key transformation involves reaction of o-nitropicolines with aromatic aldehydes in the presence of TBAF and Hünig's base giving rise to functionalized products having molecular complexity suitable for further manipulation. 相似文献
12.
Synthesis of pyrimido[1,2-a]benzimidazole and pyrano[2,3-c]pyrazole derivatives were achieved using polyethylene glycol (PEG-400) as promoting reaction medium in water under catalyst-free conditions at reflux and room temperature, respectively. The structure of pyrimido[1,2-a]benzimidazole was confirmed using 1H NMR, 13C NMR, DEPT, and HMBC experiments. The promising points for the present methodology are efficiency, generality, high yield, short reaction time, cleaner reaction profile, ease of product isolation, simplicity, potential of recycling reaction medium, and finally agreement with green chemistry protocols. 相似文献
13.
A. Hajri R. Abderrahim 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):520-525
Abstract The reaction of thionyl chloride with amidines 2, derived from N-benzimidazol-2-yl imidates 1, leads to [1,2,4,6]thiatriazino[2,3-a][1,3]benzimidazol-1(2H)-one 3 in good yields. [1,3,5]Thiadiazino[3,4-a][1,3]benzimidazol-2-imine 4 was prepared by condensation of NaSCN with benzimidazol-2-yl imidate 1. The isolated compounds 3 and 4 were identified by spectroscopic methods including IR, 1H NMR, and 13C NMR as well as elemental analyses and MS of 3d and 4b. GRAPHICAL ABSTRACT 相似文献
14.
Yuh-Wen Ho 《中国化学会会志》1999,46(1):91-96
The reaction of 3-amino-4,6-dimethyl-2-thieno[2,3-b]pyridine carbohydrazide ( 1 ) with appropriate chalcones 2a-2d in the presence of acid catalyst produced the corresponding 3-amino-2-[(3,5-disubstituted-pyrazolin-1-yl)carbonyl]-4,6-dimethylthieno[2,3-b]pyridines 3a-3d . 3-Amino-2-[(3-substituted-pyrazolin-1-yl)carbonyl]-4,6-dimethylthieno[2,3-b]pyridines 7a, 7b were also obtained by the cyclization reaction of carbohydrazide 1 with Mannich base derivatives 6a, 6b under basic condition. 相似文献
15.
E. Yu. Kambulov V. K. Vasilin E. A. Kaigorodova L. D. Konyushkin G. D. Krapivin 《Chemistry of Heterocyclic Compounds》2003,39(2):255-266
Derivatives of a new heterocyclic system - benz[4,5]imidazo[1,2-c]pyrido[3',2';4,5]thieno[2,3-e]pyrimidine have been obtained by successive reactions in three stages - alkylation of 3-cyanopyridine-2(1H)-thiones with 2-chloromethylbenzylimidazole to give 2-benzimidazolylmethylthio-3-cyanopyridines, closing the thiophene ring in the latter to form 3-amino-2-(benzimidazolyl-2)thieno[2,3-b]pyridines, and cyclization of the pyrimidine ring by acylation with carboxylic acid anhydrides or chlorides. 相似文献
16.
A. M. Kamal El-Dean M. S. A. El-Gaby A. M. Gaber H. A. Eyada A. S. N. Al-Kamali 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):413-424
Abstract Novel series of thieno[2,3-c]pyridazines and pyrimido[4′,5′:4,5] thieno-[2,3-c]pyridazines have been synthesized from the readily accessible 4-cyano-5,6-dimethylpyridazin-3(2H)-thione 3b. 相似文献
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18.
[2,3]-Wittig rearrangements of (E)-3-aza-allylic alcohol derivatives can provide access to syn or anti optically enriched 1,2-aminoalcohols by using a chirality transfer or a chiral auxiliary. 相似文献
19.
An operationally simple, catalyst-free, and efficient protocol for the synthesis of novel 4H-indeno[1,2-b]furan-4-one and furo[2,3-d]pyrimidine derivatives by a one-pot reaction of 2-aminopyridines, 1,3-indandione, or barbituric acid and phenylglyoxal monohydrate in water at reflux, involving domino aldol condensation, Michael addition, and ring-closing reactions is described. This transformation has several advantages, including high yield, short reaction duration, simple workup, and simple purification. 相似文献
20.
A series of Ce1MgxZr1-xO2 mixed metal oxides with different molar ratios were prepared by simple co-precipitation and were characterized by X-ray diffraction, infrared spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, temperature-pro- grammed desorption of CO2, and N2 adsorption techniques. The prepared materials were tested for catalytic activity by the synthesis of tet-rahydrobenzo[b]pyran derivatives using a three component reaction (aromatic aldehydes, malononitrile, and dimedone) in an ethanol me-dium. The best catalytic activity was obtained with Ce1Mg0.6Zr0.4O2. The particle size or crystallite size was estimated using the De-bye-Scherrer equation. The addition of magnesium oxide into the ceria-zirconia lattice resulted in the formation of nanosized particles rang-ing from 5.41 to 9.78 nm. This work describes the catalytic behavior of magnesium oxide in mixed metal oxide systems. 相似文献