共查询到20条相似文献,搜索用时 31 毫秒
1.
Astrid Lumetzberger Werner Löwe Manuela Weber Peter Luger 《Journal of heterocyclic chemistry》2007,44(1):155-159
The (Z)‐3‐substituted 2‐indolinone 6 was prepared using the aldehydes 4 and 8 unknown up to now and 2‐indolinone. 相似文献
2.
Xiao‐Xia Ye Jin Zhang An‐Jiang Zhang Li‐Xue Zhang 《Journal of heterocyclic chemistry》2008,45(4):987-991
A series of novel 6‐aryl‐3‐(1,2,3,4‐tetrahydroxybutanol‐1‐yl)‐7H‐1,2,4‐triazolo[3,4‐b][1,3,4]thiadiazines were easily synthesized in high yields by means of the reactions of 4‐amino‐5‐(1,2,3,4‐tetrahydroxybutyl)‐2,4‐dihydro‐3H‐1,2,4‐triazole‐3‐thione ( 1 ) with substituted ω‐bromoacetophenones or ω‐chloroacetophenone. Nearly all of the title compounds possess plant growth‐promoting activities. 相似文献
3.
Minoo Dabiri Hamid Arvin‐Nezhad Hamid R. Khavasi Ayoob Bazgir 《Journal of heterocyclic chemistry》2007,44(5):1009-1011
Pyrimido[4,5‐d]pyrimidine‐2,5‐dione derivatives have been synthesized in high yields in a novel, onepot, and efficient process by condensation of 6‐amino‐3‐methyl‐2‐(methylthio)pyrimidin‐4(3H)‐one, aldehydes and urea under microwave‐assisted conditions. 相似文献
4.
A series of 3‐[(6‐chloropyridin‐3‐yl)methyl]‐6‐substituted‐6,7‐dihydro‐3H‐1,2,3‐triazolo[4,5‐d]pyrimidin‐7‐imines were designed and synthesized via a multi‐step sequence using 2‐chloro‐5‐(chloromethyl)‐pyridine as the starting material. Various primary aliphatic amines, hydrazine and hydrazide reacted with 3 to obtain the cyclization products 4 . Their structures were confirmed by 1H NMR and elemental analyses, some of them were also confirmed by IR, 13C NMR, MS and single crystal X‐ray diffraction. The preliminary bioassay indicated that some of the target compounds 4 displayed moderate to weak fungicidal activity and insecticidal activity. 相似文献
5.
Nilo Zanatta Deise M. Borchhardt Darlene C. Flores Helena S. Coelho Tiago M. Marchi Alex F. C. Flores Helio G. Bonacorso Marcos A. P. Martins 《Journal of heterocyclic chemistry》2008,45(2):335-341
This paper describes the synthesis and characterization of a new series of 4‐substituted‐3‐ethoxycarbonyl‐6‐trifluoromethyl‐(1,2,3)‐oxathiazinane‐S‐oxides and 3‐(4,6‐diphenyl‐pyrimidin‐2‐yl)‐6‐trifluoromethyl‐(1,2,3)oxathiazinane‐S‐oxides from the cyclization reaction of 4,4,4‐trifluoro‐3‐hydroxybutylcarbamates and 4‐(4,6‐diphenyl‐pyrimidin‐2‐ylamino)‐1,1,1‐trifluoro‐butan‐2‐ols with thionyl chloride. The analysis of the NMR data allowed us to define important features of the molecular structure. Significant chemical and structural differences were observed between the trifluoromethylated oxathiazinanes obtained in this work from other analogue compounds reported in the literature. 相似文献
6.
Saifidin Safarov Muhamacho A. Kukaniev Elena Karpuk Herbert Meier 《Journal of heterocyclic chemistry》2007,44(1):269-271
7H‐1,3,4‐Thiadiazolo[3,2‐a]pyrimidin‐7‐ones can be prepared by the acylation of 5‐amino‐1,3,4‐thiadiazoles with diketene and subsequent ring closure (dehydration). Whereas arylthio substituents (SC6H5) can be introduced in 2‐position by the replacement of Br, alkylthio groups (SC2H5) have to be already presentin the starting 5‐amino‐1,3,4‐thiadiazole. The ambident nucleophile 2‐thiazolidinethione reacts in the Br substitution reaction on the N atom. 相似文献
7.
Dorota Prukala 《Journal of heterocyclic chemistry》2007,44(5):1207-1211
Simple alkylation of 5‐(aminodialkyl)methylcytosine a‐d gives twelve new, potentially biologically active 1N o‐(m‐ or p‐) bromobenzyl derivatives of 5‐substituted cytosine 1‐12 with high regioselectivity. The structures of all compounds have been confirmed by elemental analysis, IR, 1H NMR and 13C NMR spectroscopic measurements. 相似文献
8.
The carbodiimides 5 , obtained from reactions of iminophosphorane 4 with aromatic isocyanates, reacted with amines, phenols or ROH to give 2‐substituted 5,6,7,8‐tetrahydropyrido[4′,3′:4,5]thieno[2,3‐d]‐pyrimidin‐4(3H)‐one 7 in the presence of catalytic amount of sodium alkoxide or solid potassium carbonate in satisfactory yields. 相似文献
9.
Eduardo Cortés Erik Peréz Ramírez Olivia García‐Mellado de Cortés 《Journal of heterocyclic chemistry》2007,44(1):189-192
A new synthesis to obtain eight novel derivatives of 1‐[(p‐substituted)phenyl]‐3a‐[(o‐ and p‐substituted)‐phenyl]‐5‐chloro‐9‐methylthio‐10,3a‐dihydro‐[1,2,4]‐oxadiazolo[2,3‐b][1,4]benzodiazepines with possible biological and pharmacological activity as anxiolytics, hypnotics, anticonvulsants in the central nervous system. The final products were obtained by condensation between 2‐methylthio‐5‐[(o‐; p‐substituted)‐phenyl]‐3H‐7‐chloro‐[1,4]benzodiazepine with benzonitrile oxide generated in situ from benzohydroxamoyl chloride in triethylamine. The structure of all products was corroborated by ir, 1H‐nmr, 13C‐nmr, with experiments bidimensional and ms in low and high resolution. 相似文献
10.
Yann Ferrand Dr. Emmanuel Klein Dr. Nicholas P. Barwell Matthew P. Crump Dr. Jesus Jiménez‐Barbero Prof. Cristina Vicent Dr. Geert‐Jan Boons Prof. Sampat Ingale Anthony P. Davis Prof. 《Angewandte Chemie (International ed. in English)》2009,48(10):1775-1779
Changing employment : Receptor 1 binds β‐N‐acetylglucosaminyl (β‐GlcNAc) up to 100 times more strongly than it does glucose. This synthetic lectin shows affinities similar to wheat germ agglutinin (WGA), a natural lectin used to bind GlcNAc. Remarkably, 1 is more selective than WGA. It favors especially the glycoside unit in glycopeptide 2 , a model of the serine‐O‐GlcNAc posttranslational protein modification.
11.
Yoshihisa Okamoto Yoshimi Yamaguchi Mitsuaki Maeda Yoshihisa Kurasawa 《Journal of heterocyclic chemistry》2008,45(3):717-721
Fused tetracycles, 6‐alkyl‐3‐alkoxy‐2‐cyano‐4,5,6a,11‐tetraazabenzo[a]fluorene derivatives ( 5a , b , c , d , e , f ), are synthesized from 2‐alkoxy‐5‐(benzimidazol‐2‐ylidene)‐3‐cyano‐6‐imino‐5,6‐dihydro‐pyridines ( 4b , c ), and when refluxed in ethyl orthoacetate or ethyl orthopropionate, the elecrophilic aromatic substitution occurs at the ortho position of the cyanopyridine ring in the fused tetracycles ( 5b , c , e , f ) to afford 6‐alkyl‐3‐alkoxy‐2‐cyano‐1‐ethyl‐4,5,6a,11‐tetraazabenzo[a]fluorenes( 6b , c , e , f ). 相似文献
12.
Kunlun He Guofu Qiu Xianming Hu Houjun Lv Junbo Wang 《Journal of heterocyclic chemistry》2008,45(2):365-369
A series of novel heterocycles 1‐aryl‐ or alkyl‐substituted‐4‐arylazamethylene‐6‐arylpyrazolo[5,4‐d]‐1,3‐oxazines were synthesized from the acylation of (5‐amino‐1‐substituted‐pyrazol‐4‐yl)‐N‐carboxamide in 63‐89% isolated yields at room temperature within 12 hours. The structure was confirmed by X‐ray crystal analysis. 相似文献
13.
The condensation products of 2‐aminoethanol or 3‐aminopropanol (bearing an alkyl substituent on the carbon adjacent to the nitrogen) with substituted benzaldehydes proved to exist in CDCl3 at 300 K as threecomponent tautomeric mixtures of the diastereomeric five‐ or six‐membered 1,3‐O,N‐heterocyclic ring forms and the corresponding imines. For each equilibrium, the electronic effects of the 2‐aryl substituents were characterized by the Hammett equation. The steric effects of the alkyl groups could be described by Hansch‐type equations for the equilibria involving oxazolidine ring forms. While the alkyl substituents did not cause any significant effect on the ring cis‐chain and the ring trans‐chain equilibria for tetrahydro‐1,3‐oxazines, increasing bulk of the 4‐alkyl group increased the stability of the cyclic tautomers for the analogous oxazolidines. 相似文献
14.
Suzan Ibrahim Aziz Hany Fakhry Anwar Mohamed Hilmy Elnagdi Daisy Hanna Fleita 《Journal of heterocyclic chemistry》2007,44(3):725-729
Efficient route to 5‐acyl‐2‐substituted‐1,2,3‐triazol‐4‐amines via reaction of 3‐oxo‐2‐(arylhydrazono)‐pentanenitrile with hydroxylamine hydrochloride is reported. X‐ray crystal structure has been made to confirm the structure of reaction products. 相似文献
15.
16.
Cherukupally Praveen Javvaji Rama Rao Padi Pratap Reddy Kaga Mukkanti Gade Srinivas Reddy 《Journal of heterocyclic chemistry》2008,45(4):1083-1087
8‐Oxa‐4b,7‐diaza‐benzo[a]azulene‐9‐one system, a new tricyclic heterocyclic framework is designed through a simple and convenient synthetic sequence. Its 6‐aryl derivatives are synthesized starting from ethyl indole‐2‐carboxylate. Reaction of differently substituted phenacyl bromides with ethyl indole‐2‐carboxylate, treatment of the resultant N‐substituted indole‐2‐carboxylates with hydroxylamine hydrochloride to provide corresponding oximes, subsequent ester hydrolysis followed by dehydrative cyclisation furnished the desired compounds 5 a‐g . 相似文献
17.
M. Sarangapani D. Sridhar M. Arjun M. Adharvana Chari 《Journal of heterocyclic chemistry》2008,45(4):1187-1190
An efficient synthesis of some novel 2‐substituted‐N‐aryl‐benzoxazole‐5‐carboxamides from 2‐substituted — 5‐carbomethoxy benzoxazole on treatment with different substituted anilines promoted by cobalt dipyridine dichloride as a catalyst is described. This new approach has the advantage of excellent yields (90%) and short reaction times 1‐2 h. 相似文献
18.
Brahim Bennani Bouchra Filali Baba Najib Ben Larbi Abdelatif Boukir Abdelali Kerbal Mostafa Mimouni Taibi Ben Hadda Bartosz Trzaskowski Abraham F. Jalbout 《Journal of heterocyclic chemistry》2007,44(3):711-716
A series of seven new 2′,3′,4′‐substituted spiro[isothiochromene‐3,5′‐isoxazolidin]‐4(1H)‐ones ( 7‐13 ) has been prepared in the reaction of benzylidene(phenyl)azane oxide ( 5 ) or benzylidene(methyl)azane oxide ( 6 ) with (3Z)‐3‐(4‐substituted‐benzylidene)‐1H‐isothio‐ chromen‐4(3H)‐one ( 1‐4 ). The reaction occurs by a 1,3‐dipolar cycloaddition mechanism that leads to the regiospecific formation of various spiroisoxazolidines ( 7‐13 ). 相似文献
19.
Ramaiyan Manikannan Shanmugam Muthusubramanian 《Journal of heterocyclic chemistry》2008,45(4):1207-1210
Reaction of 2‐(5‐substituted‐2‐hydroxybenzylamino)phenols ( 2 ) with formalin in ethanol under reflux has chemoselectively led to 2‐(6‐substituted‐2H—benzo[e][1,3]oxazin‐3(4H)‐yl)phenols ( 3 ) in good yield involving the ring closure of the hydroxyl group of the C‐aryl ring and not that of the N‐aryl ring. 相似文献
20.
Hanan Al‐Awadi Maher R. Ibrahim Nouria A. Al‐Awadi Yehia A. Ibrahim 《Journal of heterocyclic chemistry》2008,45(3):723-727
Flash vacuum pyrolysis (FVP) of 1‐acylbenzotriazole phenylhydrazones gave benzonitriles, aniline and 2‐arylbenzimidazole derivatives. Static pyrolysis of the same substrates at 180 °C gave exclusively the corresponding N‐anilino‐2‐arylbenzimidazole derivatives. Pyrolysis of the isomeric 2‐acylbenzotriazole phenylhydrazones gave similar products. 相似文献