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1.
Shrikant B. Kanawade Shivaraj P. Patil Prashant S. Nikam Sachin A. Gangurde Madhukar N. Jachak Raghunath B. Toche 《Journal of heterocyclic chemistry》2012,49(2):363-369
o‐Aminothiophene dicarbonitrile 1 on neat reaction with cyclic ketones in anhydrous ZnCl2 yielded mixture of fused aminopyridine 3 and iminospirooxazine 4 derivatives. Similarly, pyrimidine derivatives 5 and 8 were obtained by the reaction of this intermediate 1 with formic acid and DMF‐DMA followed by hydrazine hydrate, respectively. The reaction of o‐amino‐thiophene dicarboxamide 2 at ambient temperature with cyclic ketones yielded spiropyrimidine 10 as a sole product in quantitative yield. The regioselective anellated pyrimidine 9 , 11 , and dihydropyrimidine 12 derivatives were also obtained by the reaction with aromatic aldehydes in presence of piperidine and iodine respectively. J. Heterocyclic Chem., (2012). 相似文献
2.
A new synthesis of 6‐carbomethoxy‐1,2,3,5‐tetrahydroirnidazo[2,3‐b][1,3]benzodiazocines 13 by the intramolecular cycloaddition reaction of methyl 2‐(1‐aziridinylmethyl)‐3‐(2‐ureidophenyl)propenoates 10 under Appel's dehydration conditions is described. The latter were readily obtained from 2‐nitrobenzalde‐hyde with methyl acrylate through the Baylis‐Hillman reaction. 相似文献
3.
Maisa I. Abdel Moneam Ahmed A. Geies Galal M. El‐Naggar Soliman M. Mousa 《中国化学会会志》2004,51(6):1357-1366
Sodium salt of 4‐hydroxy‐6‐methyl‐2‐phenylpyrimidine‐5‐carbonitrile ( 3 ) was subjected to alkylation with different a‐halo compounds, where the corresponding O‐alkylated products 4a‐g were obtained. Ring closure of the O‐alkylated product 4a‐c performed using sodium ethoxide in refluxing ethanol afforded furo[2,3‐d]pyrimidines 5a‐c The latter compounds on reaction with a variety of reagents gave other new furopyrimidines as well as a number of furodipyrimidines. 相似文献
4.
Maria Tsoukka Konstantinos E. Litinas Demetrios N. Nicolaides Dimitra J. Hadjipavlou‐Litina 《Journal of heterocyclic chemistry》2007,44(3):529-534
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6.
Exploration of the Photodegradation of Naphtho[2,3‐g] quinoxalines and Pyrazino[2,3‐b]phenazines
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Dr. Nicole Kolmer‐Anderl Dr. Andreas Kolmer Prof. Dr. Christina M. Thiele Prof. Dr. Matthias Rehahn 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(15):5277-5287
Nitrogen‐containing polycyclic aromatic hydrocarbons are very attractive compounds for organic electronics applications. Their low‐lying LUMO energies points towards a potential use as n‐type semiconductors. Furthermore, they are expected to be more stable under ambient conditions, which is very important for the formation of semiconducting films, where materials with high purity are needed. In this study, the syntheses of naphtho[2,3‐g]quinoxalines and pyrazino[2,3‐b]phenazines is presented by using reaction conditions, that provide the desired products in high yields, high purity and without time‐consuming purification steps. The HOMO and LUMO energies of the compounds are investigated by cyclic voltammetry and UV/Vis spectroscopy and their dependency on the nitrogen content and the terminal substituents are examined. The photostability and the degradation pathways of the naphtho[2,3‐g]quinoxalines and pyrazino[2,3‐b]phenazines are explored by NMR spectroscopy of irradiated samples affirming the large influence of the nitrogen atoms in the acene core on the degradation process during the irradiation. Finally, by identifying the degradations products of 2,3‐dimethylnaphtho[2,3‐g]quinoxaline it is possible to track down the most reactive position in the compound and, by blocking this position with nitrogen, to strongly increase the photostability. 相似文献
7.
《Journal of heterocyclic chemistry》2017,54(5):2874-2880
In the present investigation, the synthesis of a series of structurally new and interesting tert‐butyl‐ and bromo‐functionalized [1,2,4]triazino[5,6‐b ]indoles ( 6a – f ) and indolo[2,3‐b ]quinoxalines ( 8a – f ) has been achieved, involving the condensation reaction of 7‐bromo‐5‐tert‐butylisatins ( 4a – f ) with thiosemicarbazide ( 5 ) and benzene‐1,2‐diamine ( 7 ). The substrates 4a – f were prepared through bromination reaction of 5‐tert‐butylisatin ( 3 ) with NBS in PEG‐400 followed by alkylation reaction. The molecular structures of these newly synthesized compounds were elucidated on the basis of their elemental analyses and spectral data. 相似文献
8.
Kazuko Shirai Koushi Fukunishi Dongfeng Hou Masaru Matsuoka 《Journal of heterocyclic chemistry》2000,37(5):1299-1304
Previously synthesized 2‐(3′‐chloro‐5′,6′‐dicyanopyrazin‐2′‐yl)cyclopentan‐1‐one 1 , obtained from the reaction of 2,3‐dichloro‐5,6‐dicyanopyrazine with 1‐pyrrolidino‐1‐cyclopentene, was further reacted with primary alkylamines to give mixtures of diastereomer of 5‐alkyl‐2,3‐dicyano‐5a,8a‐dihy‐dro‐5a‐hydroxycyclopentano[1′,2′:4,5]pyrrolo[2,3‐b]pyrazines 3a‐h in high yield. The reaction of 2‐alkylamino‐3‐chloro‐5,6‐dicyanopyrazine with 1‐pyrrolidino‐1‐cyclohexene gave 5‐alkyl‐2,3‐dicyanocyclopentano[1′,2′:4,5]pyrrolo[2,3‐b]pyrazines 5a‐b together with 5‐alkylamino‐2,3‐dicyano‐6‐pyrrolidinopyrazines 6a‐b . The products prepared are all of interest as potential pesticides and new fluorescent chromophores. 相似文献
9.
Zhong‐Xia Wang Li‐Zhuang Chen Bei Li Guang‐Fan Han 《Journal of heterocyclic chemistry》2015,52(6):1663-1668
The Gewald reactions of 5‐substituted‐1,3‐cyclohexanedione, malononitrile, and powdered sulfur were carried out to give the corresponding products 2‐amino‐5‐substituted‐7‐oxo‐4,5,6,7‐tetrahydrobenzo[b]thiophene‐3‐carbonitrile derivatives 1 . The intermediate enamines 2 were prepared by reaction of compounds 1 and 5‐substituted‐1,3‐cyclohexanedione with hydrochloric acid as catalyst. The title compounds 11‐amino‐2,8‐substituted‐2,3,8,9‐tetrahydrobenzo[4,5]thieno[2,3‐b]quinolinone 3 were synthesized by cyclization of compounds 2 in the presence of K2CO3 and Cu2Cl2. The structures of all compounds were characterized by elemental analysis, IR, MS, and 1H‐NMR spectra. 相似文献
10.
Amrah Nouri Ahmad Poursattar Marjani Jabbar Khalafy 《Journal of heterocyclic chemistry》2019,56(10):2912-2921
A new series of benzo[g]thiazolo[2,3‐b]quinazolin‐4‐ium and benzo[g]benzo[4,5]thiazolo[2,3‐b]quinazolin‐14‐ium hydroxide derivatives have been synthesized by the one‐pot, three‐component reaction of aryl glyoxal monohydrates, 2‐hydroxy‐1,4‐naphthoquinone, and 2‐aminothiazole or 2‐aminobenzothiazole in the presence of triethylamine and p‐toluenesulfonic acid as organocatalysts in H2O/acetone (2:1) at room temperature. This method offers mild reaction conditions, excellent yields, easy workup, and readily accessible starting materials and catalysts. 相似文献
11.
Ramin Ghahremanzadeh Mojtaba Mirhosseini Moghaddam Ayoob Bazgir Mohammad Mehdic Akhondi 《中国化学》2012,30(2):321-326
A four‐component reaction in the presence of Alum [KAl(SO4)2·12H2O] as an inexpensive and reusable catalyst using the ionic liquid as an effective green reaction media is reported. 相似文献
12.
《Journal of heterocyclic chemistry》2017,54(1):648-652
Novel derivatives of benzo[h ]thieno[2,3‐b ]quinoline‐9‐yl(aryl)methanone were synthesized in good yield and short reaction times by reaction of 2‐mercaptobenzo[h ]quinoline‐3‐carbaldehyde with phenacyl bromides under basic conditions. All compounds were characterized using Fourier transform infrared, 1H nuclear magnetic resonance and 13C nuclear magnetic resonance, spectral data, and elemental analysis. 相似文献
13.
《Journal of heterocyclic chemistry》2017,54(4):2287-2296
An efficient one‐pot method for synthesis of new biologically active thiazolo[3,2‐a ]pyrimidine and thiazolo[2,3‐b ]quinazoline derivatives is described via reaction of pentachloropyridine with fused pyrimidine‐2(5H )‐thiones or quinazoline‐2(1H )‐thiones. These reactions were carried out in the presence of potassium carbonate as a base in acetonitrile as a solvent to produce products 3a – n in good‐to‐excellent yield. Pentachloropyridine is doubly electrophilic building blocks for the formation of ring annulated thiazolo[3,2‐a ]pyrimidine and thiazolo[2,3‐b ]quinazoline products. 相似文献
14.
Syntheses of New Unsymmetrical 2,5‐Disubstituted‐1,3,4‐oxadiazoles and 1,2,4‐Triazolo[3,4‐b]‐1,3,4‐thiadiazoles Bearing Thieno[2,3‐c]pyrazolo Moiety
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Shivaraj P. Patil Shrikant B. Kanawade Dinesh C. Bhavsar Prashant S. Nikam Sachin A. Gangurde Raghunath B. Toche 《Journal of heterocyclic chemistry》2014,51(2):368-373
New series of (thieno[2,3‐c]pyrazolo‐5‐yl)‐[1,2,4]triazolo[3,4‐b][1,3,4]thiadiazoles 10a , 10b , 10c and (thieno[2,3‐c]pyrazol‐5‐yl)‐1,3,4‐oxadiazol‐3(2H)‐yl)ethanones 6a , 6b , 6c has been synthesized from thieno[2,3‐c]pyrazole‐5‐carbohydrazide 3 by multistep reaction sequence. (5‐Aryl‐1,3,4‐oxadiazol‐2‐yl)‐1H‐thieno[2,3‐c]pyrazoles 4a , 4b , 4c were also synthesized from thieno[2,3‐c]pyrazole‐5‐carbohydrazide 3 by cyclization with various aromatic carboxylic acids. The hydrazide 3 was obtained by reaction of thieno[2,3‐c]pyrazole‐5‐carboxylate 2 with hydrazine hydrate in good yield, and compound 2 was obtained by the reaction of 5‐chloro‐3‐methyl‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde 1 and 2‐ethyl thioglycolate in presence of sodium alcoholate in good yield. 相似文献
15.
Richard C. Effland Beth Ann Gardner Joseph Strupczewski 《Journal of heterocyclic chemistry》1981,18(4):811-814
The synthesis of 2,3-dihydrospiro[benzofuran-2,4′-piperidines] 3 and 2,3-dihydrospiro[benzofuran-2,3′]-pyrrolidine] 6 is described. The synthesis was achieved by a Grignard reaction of a 2-fluorobenzylhalide with an appropriate cycloazaalkyl ketone to yield the tertiary alcohols 1 and 4 . Subsequent intramolecular displacement of the aromatic fluoride by the derived alkoxides provided the novel system. Nitration of 1′-acetyl-2,3-dihydrospiro[benzofuran-2,4′-piperidine] 7 resulted in a 5-nitro derivative. 相似文献
16.
The title compounds substituted 2‐lactosylthiothieno[2,3‐d]pyrimidin‐4‐ones 6 were synthesized by the glycosyl reaction and alcoholysis reaction of substituted 2‐thioxo‐thieno[2,3‐d]pyrimidin‐4‐ones 4 ,which is formed by the base catalytic and acetic acidify reaction of amino esters 2 with alkyl or arylisothiocyanates and hepta‐O‐acetyl‐lactosyl bromide in good yields. All of the compounds were confirmed by NMR, ESI‐MS, and elemental analysis. 相似文献
17.
Synthesis of Naphthalene Functionalized Trans‐2,3‐dihydrofuro[3,2‐c]coumarins as Antioxidant and Anthelmintic Agents
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Deepak Wadhwa Varun Arora Loveena Arora Pragi Arora Om Parkash 《Journal of heterocyclic chemistry》2016,53(4):1030-1035
A series of trans‐2,3‐dihydrofuro[3,2‐c]coumarins ( 4 ) has been synthesized by a one‐pot multicomponent reaction by aromatic aldehydes, 4‐hydroxycoumarin, α‐tosyloxyketones, and pyridine using triethylamine as catalysts in acetonitrile. The synthesized compounds were then screened for their antioxidant and anthelmintic activities. 相似文献
18.
《Journal of heterocyclic chemistry》2018,55(1):91-96
Reaction of 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij]quinoline‐1,2‐dione ( 1 ) with two equivalents of some 6‐aminouracils (or 6‐amino‐2‐thiouracil) generates spirocyclic tetrahydrobenzo[if]quinolizines ( 7 ). The one‐pot, three‐component reaction of amido ketone ( 1 ) with 6‐aminouracil (or 6‐amino‐2‐thiouracil) and a cyclic six‐membered 1,3‐diketone produces spirocyclic tetrahydropyrrolo[3,2,1‐ij]quinolinones ( 15 ). 相似文献
19.
Kumaresan Prabakaran Matthias Zeller Paul S. Szalay Karam J. Rajendra Prasad 《Journal of heterocyclic chemistry》2012,49(6):1302-1309
Previously not easily accessible pyrano[2,3‐a]carbazoles were synthesized in highly convergent syntheses avoiding multistep procedures from readily available 1‐hydroxycarbazoles. Substituted pyrano[2,3‐a]carbazoles were produced by three different methods by treatment of the 1‐hydroxycarbazoles with dimethyl acetylene dicarboxylate (DMAD) and triphenylphoshine, by reaction with ethyl 2‐methylacetoacetate in the presence of ZnCl2/POCl3, and by reaction with trifluoroacetic acid followed by Wittig reaction with (carbethoxymethylene) triphenylphosphorane. The article also highlights the optimization of reaction conditions and strategies to avoid formation of byproducts for all three types of reactions. 相似文献
20.
Sciji Yamaguchi Hideo Saitoh Masahide Kurosaki Hajime Yokoyama Yoshiro Hirai Shunsaku Shiotani 《Journal of heterocyclic chemistry》1999,36(1):1-9
Bromination of α‐cyanopyridine derivatives of furopyridines 1a‐d gave the 2,3‐dibromo‐2,3‐dihydro compounds 2a‐d in excellent yields. Treatment of 2a‐d with sodium hydroxide in methanol yielded compounds formed through the dehydrobromination and solvolysis of the nitrile. N‐Oxidation of 1a and 1b gave N‐oxide in much poor yield, while 1c and 1d gave the N‐oxide 13c and 13d in good yields. The nucleophilic reactions (cyanation, chlorination and acetoxylatoin) of 13c through a Reissert‐Henze type reaction gave poor results, which would be caused by the strong electron withdrawing effect of the cyano group. 相似文献