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1.
Shambabu Joseph Maddirala Vidya S. Gokak Linganagouda D. Basanagoudar 《Journal of heterocyclic chemistry》2004,41(1):7-11
3‐Benzylindole‐2‐carbohydrazides (4) on reaction with triethylorthoformate in a polar solvent like DMF yielded only 10‐benzyl‐1,2‐dihydro‐1‐oxo‐1,2,4‐triazino[4,5‐a]indoles (5) while (4) on reaction with triethylorthoacetate in DMF yielded both 10‐benzyl‐4‐methyl‐1,2‐dihydro‐1‐oxo‐1,2,4‐triazino[4,5‐a]indoles (5) and 3‐benzyl‐2‐(5‐methyl‐1,3,4‐oxadiazol‐2‐yl)indoles (6) instead of only the triazinoindoles as expected. The oxadiazolylindoles (6) were also synthesized by refluxing (4) with excess of orthoesters. The structures of the compounds formed were characterized by their analytical and spectral data. 相似文献
2.
Viktor A. Tafeenko Stanislav I. Gurskiy Andrey N. Baranov Tatiana V. Kaisarova Leonid A. Aslanov 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(2):m52-m55
The structures of three salts of 3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olate with alkali metals (Na, K and Rb) are related to their luminescence properties. The Rb salt, rubidium(I) 3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olate, Rb+·C8HN4O2−, is isomorphous with the previously reported potassium salt. For the Na compound, sodium(I) 3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olate dihydrate, Na+·C8HN4O2−·2H2O, two independent sodium ions, located on inversion centers, are coordinated by four water molecules each and additionally by two cyano groups for one and two carbonyl groups for the other. The luminescence spectra in solution are unaffected by the nature of the cation but vary strongly with the dielectric constant of the solvent. In the solid state, the emission maxima vary with structural features; the redshift of the maximum luminescence varies inversely with the distance between the stacked anions. 相似文献
3.
Diastereoselective Synthesis of (Z)‐6‐(2‐Oxo‐1,2‐dihydro‐3H‐indol‐3‐ylidene)‐3,3a,9,9a‐tetrahydroimidazo[4,5‐e]thiazolo[3,2‐b]‐1,2,4‐triazin‐2,7(1H,6H)‐diones 下载免费PDF全文
Galina A. Gazieva Ekaterina A. Shishkova Ludmila B. Kulikova Natal'ya G. Kolotyrkina Natal'ya V. Sigay Angelina N. Kravchenko 《Journal of heterocyclic chemistry》2014,51(4):921-926
Two efficient and diastereoselective procedures for the synthesis of (Z)‐6‐(2‐oxo‐1,2‐dihydro‐3H‐indol‐3‐ylidene)‐3,3a,9,9a‐tetrahydroimidazo[4,5‐e]thiazolo[3,2‐b]‐1,2,4‐triazin‐2,7(1H,6H)‐diones by aldol‐crotonic condensation of 1,3‐dimethyl‐3a,9a‐diphenyl‐3,3a,9,9a‐tetrahydroimidazo[4,5‐e]thiazolo[3,2‐b]‐1,2,4‐triazin‐2,7(1H,6H)‐dione with isatins under acidic or basic catalysis are reported. Isomerization in (Z)‐7‐(1‐allyl‐2‐oxo‐1,2‐dihydro‐3H‐indol‐3‐ylidene)‐1,3‐dimethyl‐3a,9a‐diphenyl‐1,3a,4,9a‐tetrahydroimidazo[4,5‐e]thiazolo[2,3‐c]‐1,2,4‐triazin‐2,8(3H,7H)‐dione was observed under basic conditions. 相似文献
4.
4‐(5‐oxo‐1,2,4‐triazol‐3‐yl)‐sydnones 11 and 4‐(4‐arylamino‐5‐oxo‐1,2,4‐triazol‐3‐yl)‐sydnones 13 have been obtained from a‐chloroformylarylhydrazine hydrochloride 2 . Moreover, the intermediates, including 3, 4 , 9 and 10 , in this study are synthetically informative and valuable. It is also noteworthy that three reactants, 1, 2 and sydnonecarbaldehydes, were prepared from sydnone derivatives and their fragments. The oxidative cyclizations of sydnonecarbaldehyde semicarbazones 9 and carbazones 10 with two different oxidizing agents (Cu(ClO4)2 and Fe(ClO4)3) have been extensively examined. The reaction time and the yields of cyclizations were affected by the substituents of semicarbazones 9 and carbazones 10. 相似文献
5.
《Journal of heterocyclic chemistry》2018,55(7):1702-1708
Synthesis of a new series of trifluoromethyl‐4,5‐dihydro‐1,2,4‐oxadiazoles and trifluoromethyl‐1,2,4‐oxadiazoles have been described by utilizing the reactions between amidoximes and trifluoroacetimidoyl chlorides. Trifluoromethyl‐4,5‐dihydro‐1,2,4‐oxadiazoles have been synthesized under mild conditions such as Na2CO3, THF‐H2O, and titanium dioxide nanoparticles as catalyst in good to excellent yields. Also, trifluoromethyl‐1,2,4‐oxadiazoles have been synthesized directly from reaction of amidoximes and trifluoroacetimidoyl chlorides in a one‐pot manner in present of NaH, THF, and titanium dioxide nanoparticle as catalyst. 相似文献
6.
A simple and versatile methodology to synthesise 4‐hydroxy‐1H‐[1,2,4]triazino[4,5‐a]quinoline‐1,6(2H)‐dione from methyl 6‐fluoro‐4‐oxo‐1,4‐dihydro‐2‐quinolinecarboxylate has been developed. It involves car‐bohydrazide formation followed by a condensation with triphosgene to form the fused [1,2,4]triazino ring. In addition, the reactivity of the [1,2,4]triazino ring has been studied. 相似文献
7.
An efficient method for the preparation of 2‐substituted 4‐aryl‐4,5‐dihydro‐3,1‐benzoxazepine derivatives under mild conditions has been developed. The reaction of 2‐(2‐aminophenyl)ethanols 1 with acid chlorides in the presence of excess Et3N in THF at room temperature gave the corresponding N‐acylated intermediates 2 , which were dehydrated by treatment with POCl3 to give 2‐substituted 4‐aryl‐4,5‐dihydro‐3,1‐benzoxazepines 3 in a one‐pot reaction. 相似文献
8.
Synthesis of 1,3‐Dihydro‐3‐oxo‐2‐benzofuran‐1‐carboxylates via Intramolecular Cyclization of 2‐[2‐(Dimethoxymethyl)phenyl]‐ 2‐hydroxyalkanoates Followed by Oxidation 下载免费PDF全文
A novel and efficient method for the preparation of 1,3‐dihydro‐3‐oxo‐2‐benzofuran‐1‐carboxylates 4 under mild conditions has been developed. Thus, the reaction of [2‐(dimethoxymethyl)phenyl]lithiums, generated easily from 1‐bromo‐2‐(dimethoxymethyl)benzenes 1 , with α‐keto esters gives the corresponding 2‐[2‐(dimethoxymethyl)phenyl]‐2‐hydroxyalkanoates 2 . The TsOH‐catalyzed cyclization of these hydroxy acetals is followed by the oxidation of the resulting cyclic acetals 3 with PCC to give the desired products in satisfactory yields. The reaction of [2‐(dimethoxymethyl)‐4,5‐dimethoxyphenyl]lithium with (MeOC?O)2, followed by treatment with NaBH4 or organolithiums, affords 2‐[2‐(dimethoxymethyl)‐4,5‐dimethoxyphenyl]‐2‐hydroxyalkanoates 6 , which can similarly be transformed into the corresponding 1,3‐dihydro‐3‐oxo‐2‐benzofuran‐1‐carboxylates 7 in reasonable yields. 相似文献
9.
《Journal of heterocyclic chemistry》2017,54(4):2258-2265
The present study emphasizes on the dealklylation of 3‐aryl‐5‐alkyl‐2‐oxo‐Δ4‐1,3,4‐oxadiazoles when reacted with formamide resulting in the formation of 2‐aryl‐2H‐1,2,4‐triazol‐3(4H )‐ones as major product. Subsequent reactions of 2‐aryl‐2H‐1,2,4‐triazol‐3(4H )‐one gave triazolo[3,4‐b ][1,3,4]thiadiazoles and triazolo[3,4‐b ][1,3,4]thiadiazines derivatives incorporated with 1,2,4‐triazol‐3‐one. 相似文献
10.
Lesaw Siero Katarzyna Kie‐Kononowicz Janina Karolak‐Wojciechowska 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(2):m79-m82
The two title mononuclear compounds are four‐coordinate bis[N‐(5‐oxo‐4,4‐diphenyl‐4,5‐dihydro‐1H‐imidazolidin‐2‐ylidene)glycinato]copper(II) dimethylformamide disolvate, [Cu(C17H14N3O3)2]·2C3H7NO, (I), and five‐coordinate aquabis[N‐(5‐oxo‐4,4‐diphenyl‐4,5‐dihydro‐1H‐imidazolidin‐2‐ylidene)glycinato]copper(II) dimethylformamide disolvate, [Cu(C17H14N3O3)2(H2O)]·2C3H7NO, (II). In (I), the CuII ion lies on an inversion centre with one‐half of the complex molecule in the asymmetric unit, while in (II) there are two independent ligand molecules in the asymmetric unit, with the CuII ion and coordinated water molecule located on a general position. In both crystal structures, the complex molecules assemble in ribbons via N—H...O hydrogen‐bond networks. 相似文献
11.
A series of 3‐alkyl(aryl)‐4‐(p‐hydroxy‐phenyl)‐4,5‐dihydro‐1H‐1,2,4‐triazol‐5‐ones 2 were obtained from the reaction of alkyl (aryl) ester ethoxycarbonyl hydrazones 1 with p‐hydroxy aniline. The reaction of 1 with 1,4‐diamino benzene (1:1) to afford 3‐alkyl(aryl)‐4‐(p‐aminophenyl)‐4,5‐dihydro‐1H‐1,2,4‐triazol‐5‐ones 3 . The reaction of 3 with benzaldehyde gave 3‐alkyl(aryl)‐4‐(4′‐benzilidenamino)‐4,5‐dihydro‐1H‐1,2,4‐triazol‐5‐ones 4 . All of the above reactions occurred under microwave heating and conventional methods. Their structures were confirmed by 1H NMR, 13C NMR, IR, and elemental analyses. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:38–42, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20381 相似文献
12.
Viktor A. Tafeenko Gennady N. Panin Andrey N. Baranov Ivan N. Bardasov Leonid A. Aslanov 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(12):m541-m547
Yellow–orange tetraaquabis(3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olato‐κN3)cadmium(II) dihydrate, [Cd(C8HN4O2)2(H2O)4]·2H2O, (I), and yellow tetraaquabis(3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olato‐κN3)cadmium(II) 1,4‐dioxane solvate, [Cd(C8HN4O2)2(H2O)4]·C4H8O2, (II), contain centrosymmetric mononuclear Cd2+ coordination complex molecules in different conformations. Dark‐red poly[[decaaquabis(μ2‐3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olato‐κ2N:N′)bis(μ2‐3‐cyano‐4‐dicyanomethylene‐1H‐pyrrole‐2,5‐diolato‐κ2N:N′)tricadmium] hemihydrate], [Cd3(C8HN4O2)2(C8N4O2)2(H2O)10]·0.5H2O, (III), has a polymeric two‐dimensional structure, the building block of which includes two cadmium cations (one of them located on an inversion centre), and both singly and doubly charged anions. The cathodoluminescence spectra of the crystals are different and cover the wavelength range from UV to red, with emission peaks at 377 and 620 nm for (III), and at 583 and 580 nm for (I) and (II), respectively. 相似文献
13.
14.
The Pseudo‐Michael Reaction of 2‐Hydrazinylidene‐1‐Arylimidazolidines with Diethyl Ethoxymethylenemalonate 下载免费PDF全文
M. Aletańska‐Kozak A. A. Kaczor T. M. Wróbel A. E. Kozioł K. Suwińska I. Dybała K. Pihlaja D. Matosiuk 《Journal of heterocyclic chemistry》2016,53(2):571-578
The pseudo‐Michael reaction of 2‐hydrazinylidene‐1‐arylimidazolidines with diethyl ethoxymethylenemalonate (DEEM) was investigated. The reaction yields the chain adduct, namely diethyl{[2‐(1‐arylimidazolidin‐2‐ylidene)hydrazinyl]methylidene}propanedioates. This is contrary to the pseudo‐Michael reaction of DEEM with 1‐aryl‐4,5‐dihydro‐1H‐imidazol‐2‐amines that does not allow isolation of chain derivatives and leads to cyclic imidazo[1,2‐a]pyrimidine derivatives while even at thermodynamic control. At first cyclization of diethyl{[2‐(1‐arylimidazolidin‐2‐ylidene)hydrazinyl]methylidene}propanedioates leads to ethyl 1‐aryl‐5(1H,8H)oxo‐2,3‐dihydro‐imidazo[2,1‐c][1,2,4]triazepine‐6‐carboxylates. 1,5‐Sigmatropic shift, following the cyclization, caused isomerization of 5(1H,8H)oxo‐2,3‐dihydro‐imidazo[2,1‐c][1,2,4]triazepine‐6‐carboxylates to ethyl 1‐aryl‐5(1H)hydroxy‐2,3‐dihydroimidazo[2,1‐c][1,2,4]triazepine‐6‐carboxylates. Presence of both isomers in the reaction product was detected in the NMR spectra. The structure of all the compounds was confirmed with spectroscopic studies (1H NMR and MS). The structure of diethyl{[2‐(1‐phenylimidazolidin‐2‐ylidene)hydrazinyl]methylidene}propanedioate was also confirmed by X‐ray crystallography. In the addition reaction, thermodynamics and HOMO–LUMO orbitals of the reactants were studied by using quantum chemical calculations. 相似文献
15.
4‐Hydroxy‐2‐oxo‐2H‐1‐benzopyran‐3‐carboxaldehydes 2a‐d are prepared from 4‐hydroxy‐2‐oxo‐2H‐1‐benzopyrans 1a‐d via the Vielsmeyer Haack reaction. The 4‐hydroxy‐2‐oxo‐3‐(3′oxo‐3′‐phenylprop‐1′‐enyl)‐2H‐1‐benzopyrans 3a‐d are obtained from 2a‐d via the Claisen reaction. Refluxing compounds 3a‐d with hydrazine hydrate gave the 3‐phenyl‐5‐(4‐hydroxy‐2‐oxo‐2H‐1‐benzopyran‐3‐yl)‐1,4,5‐trihydropyra‐zols 4a‐d . Stirring compounds 2a‐d with semicarbazide hydrochloride in acidic medium gave the 4‐hydroxy‐2‐oxo‐2H‐1‐benzopyran‐3‐aldehyde‐semicarbazone 5a‐d , which on cyclisation with ferric chloride hexahydrate gave the 5‐(4‐hydroxy‐2‐oxo‐2H‐1‐benzopyran‐3‐yl)‐2,4‐dihydro[1,2,4]triazol‐3‐ones 6a‐d . All these compounds show significant antibacterial activities. 相似文献
16.
Kenji Yamagata Fumi Okabe Hiroshi Maruoka Yoshinobu Tagawa 《Journal of heterocyclic chemistry》2005,42(4):543-549
The reaction of 2‐acylamino‐4,5‐dihydro‐3‐furancarbonitriles 1 with sodium iodide in N,N‐dimethyl‐formamide gave the corresponding 1‐acyl‐2‐oxo‐3‐pyrrolidinecarbonitriles 2 in good yields. Successive treatment of 1 with titanium(IV) chloride and potassium carbonate resulted in the formation of N‐acyl‐1‐cyanocyclopropanecarboxamides 4 . The same compounds 2 were also obtained by treatment of 4 with sodium iodide. The starting compounds 1 were synthesized by the reaction of 2‐amino‐4,5‐dihydro‐3‐furan‐carbonitrile with acyl chlorides in pyridine. 相似文献
17.
Amal Feddouli Moulay Youssef Ait Itto Aïssa Hasnaoui Didier Villemin Paul‐Alain Jaffrs Jana Sopkova‐De Oliveira Santos Abdelkhalek Riahi FranOis Huet Jean‐Claude Daran 《Journal of heterocyclic chemistry》2004,41(5):731-735
Herein we report an efficient one pot synthesis of new chiral 4,5‐dihydro‐4‐arylspiro[1,3,4‐thiadiazole]‐5,2′‐camphane‐2‐carboxylic acid ethyl esters 5–7 and 4,5‐dihydro‐3‐arylspiro[1,4,2‐oxathiazole]‐5,2′‐camphane 11–13 , using 1,3‐dipolar cycloaddition of nitrilimines 2–4 and nitrile oxides 8–10 to (1R)‐thiocamphor 1 respectively. The structure of the newly prepared 1,3,4‐thiadiazoles 5–7 (obtained as pure diastereoisomers) were fully established via spectroscopic analysis and X‐ray structural analysis which proved the absolute configuration of the C5 spiranic carbon to be (R). NMR spectral analysis were also very useful to show the new 1,4,2‐oxathiazoles 11–13 are mixtures of two (5R)/(5S) diastereoisomers with the ratio 6:4,7:3 and 6:4 respectively. 相似文献
18.
KhalidMohammed Khan Shagufta Rahat MuhammadIqbal Choudhary Atta‐ur‐Rahman Usman Ghani Shahnaz Perveen Shagufta Khatoon Ahsana Dar Abdul Malik 《Helvetica chimica acta》2002,85(2):559-570
To evaluate the effect of substituents on biological activities of electron‐rich N‐containing heterocycles, the variably 2‐substituted 5,6‐dihydro‐5‐oxo‐4H‐1,3,4‐oxadiazine‐4‐propanenitriles 26 – 33 were synthesized and evaluated for antibacterial, antifungal, and enzyme‐inhibition activities. The target compounds were obtained from alkyl 4‐ or 3‐hydroxy benzoates 1 and 2 , respectively, and from methyl indoleacetate 3 . The phenolic OH group of benzoates 1 and 2 were substituted with p‐toluenesulfonyl (→ 4 and 5 ), benzoyl (→ 6 and 7 ), and benzyl groups (→ 8 and 9 ) and then converted to 5,6‐dihydro‐5‐oxo‐4H‐1,3,4‐oxadiazine‐4‐propanenitriles. To establish structure‐activity relationships (SAR), a pharmacological screening of the intervening intermediates was also conducted, which revealed that the intermediate hydrazide 11 possesses significant antimicrobial and MAO‐A inhibiting properties and intermediates 12, 24, 28 , and 29 appreciable antifungal activities. Compound 7 inhibits α‐chymotrypsin. 相似文献
19.
In the article the study of cyclocondensation of 3‐[2‐amino‐3‐(3,5‐dioxo‐2,3,4,5‐tetrahydro[1,2,4]‐triazme‐6‐yl)phenyl]‐2,3‐dihydro‐quinoxalin‐2‐one 5 is described and it was found, that the reaction does not proceed by both possible directions, but only cyclization with the carbonyl group of 6‐azauracile cycle proceeds. The 6‐(3‐oxo‐3,4‐dihydro‐quinoxaline‐2‐yl)‐4H‐2,3‐dihydro[1,2,4]triazino[5,6‐b]indol‐3‐one 6 was formed in this way. This course of cyclocondensation was confirmed by the fact, that the product 6 , mentioned above, is quite different from isomeric compound 7 , prepared unambiguously by condensation of 7‐(6‐azauracile‐5‐yl)isatine 8 with o‐phenylenediamine. 相似文献
20.
The condensation of 4‐amino‐3‐aryl‐5‐mercapto‐1, 2, 4‐triazoles (1a‐f) with 6‐/8‐substituted 1,4‐dihydro‐4‐oxo‐quinoline‐3‐carboxylic adds (2a‐d) in the presence of phosphorus oxychloride on refluxng or under microwave irradiation gave twenty four novel 3‐aryl‐6‐ (6‐/8‐substituted 4‐chloroquinoline‐3‐yl)‐s‐triazolo[3,4‐b]‐1, 3,4‐thiadiazoles (4a‐x), Considerable increase in the reaction rate has been observed with improved yields under microwave irradiation. The structures of the compounds synthesized were determined by elemental analyses, IR, 1H NMR and MS spectra. Their spectral properties and the reaction mechanism were also discussed. The preliminary biological test showed that some of compounds bad moderate antibacterial activities. 相似文献