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1.
Azita Javidnia Tahmineh Akbarzadeh Loghman Firoozpour Mehdi Khoobi Abbas Shafiee Alireza Foroumadi 《Journal of heterocyclic chemistry》2011,48(2):454-457
Starting from 5‐hydroxymethyl‐2‐mercapto‐1‐methyl‐1H‐imidazole (1), a series of 2‐(1‐methyl‐2‐methylsulfonyl‐1H‐imidazol‐5‐yl)‐5‐alkylthio and 5‐alkylsulfonyl‐1,3,4‐thiadiazole derivatives ( 9a , 9b , 9c , 9d and 10a , 10b , 10c , 10d ) were prepared as potential antimicrobial agents. The structure of the obtained compounds was confirmed by NMR, IR, Mass spectroscopy, and elemental analysis. J. Heterocyclic Chem., (2010) 相似文献
2.
《Magnetic resonance in chemistry : MRC》2003,41(4):291-295
This paper describes the complete assignment of all carbons and hydrogens of several newly synthesized 6‐substituted 2‐(2‐hydroxyaryl)benzoxazoles from 2,2′‐dihydroxydiaryl Schiff bases by the use of two‐dimensional NMR techniques. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
3.
J. Matysiak 《Journal of heterocyclic chemistry》2006,43(1):55-58
One‐stage synthesis of 5‐substituted (alkyl, aryl, heteroaryl, arylalkyl, heteroalkyl, alkoxy‐, aryloxy)‐2‐(2,4‐dihydroxyphenyl)‐1,3,4‐thiadiazoles is described. The compounds were prepared by the reaction of sulfinyl‐bis(2,4‐dihydroxythiobenzoyl) (STB) with hydrazides or carbazates. The structure of new compounds was assigned by ir, nmr and ms data. 相似文献
4.
5‐Mercapto‐1,3,4‐thiadiazole‐2(3H)‐thione: Synthesis and Structure of Alkylated Derivatives 下载免费PDF全文
Jigar K. Mistry Richard Dawes Amitava Choudhury Michael R. Van De Mark 《Journal of heterocyclic chemistry》2014,51(3):747-754
The observed structure of 1,3,4‐thiadiazolidine‐2,5‐dithione (also known as 2,5‐dimercapto‐1,3,4‐thiadiazole) has been previously reported in three different tautomeric forms including —dithiol and—dithione. This report examines the relative stability of each form and also reports synthesis and characterization of the structures of mono‐alkylated and di‐alkylated forms of 5‐mercapto‐1,3,4‐thiadiazole‐2(3H)‐thione. The methods of X‐ray crystallography, NMR spectroscopy, and ab initio electronic structure calculations were combined to understand the reactivity and structure of each compound. 相似文献
5.
Marc Fournier Robert E. Prud'homme 《Journal of polymer science. Part A, Polymer chemistry》1999,37(6):761-769
Poly‐β‐amides (nylons 3) were synthesized via the anionic polymerization of a series of 4‐alkyl‐4‐methyl‐2‐azetidinones where the alkyl group is a methyl, ethyl, propyl, butyl, or pentyl. The “non‐assisted” polymerization was conducted under vacuum, in the bulk, at 160°C, using potassium 2‐pyrrolidonate as catalyst, whereas the “assisted” polymerization was carried in dimethylsulfoxide, at room temperature, using N‐acetylpyrrolidinone‐2 as activator but it gave no polymer with a propyl or bulkier side group. Side reactions occur in all cases. X‐ray spectra showed that poly(4‐alkyl‐4‐methyl‐2‐azetidinone)s are amorphous with propyl, butyl, and pentyl groups, and semi‐crystalline with methyl or ethyl substituents. Both semi‐crystalline polyamides exhibit an extended planar zigzag conformation, with a fiber identity period along the c axis of 4.9 Å. Glass transition temperatures, melting temperatures, and/or decomposition temperatures are also reported. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 761–769, 1999 相似文献
6.
《Journal of heterocyclic chemistry》2017,54(4):2319-2325
By replacing the amide bond into 1,3,4‐oxadiazole moiety, a series of 1‐phenyl‐5‐(trifluoromethyl)‐1H‐pyrazole derivatives bearing 1,3,4‐oxadiazole were synthesized and evaluated their antibacterial and antifungal activity. The bioassay results revealed that compounds 7a and 7b showed the strongest antibacterial activity toward pathogen Xanthomonas oryzae pv. oryzae with the EC50 values of 15.0 and 6.4 µg/mL, respectively; compound 6a exhibited comprehensive antifungal activity toward six kinds of fungi; compound 6f could selectively inhibit the growth of Sclertinia sclerotiorum and Rhizoctonia solani with the inhibition rates of 82.5 and 80.3% at the concentrate of 100 µg/mL, respectively; compound 7b exerted good antifungal activity toward Fusarium oxysporum, Cytospora mandshurica, and Rhizoctonia solani with the inhibition rates of 70.8, 69.5, and 71.5%, respectively. The results suggested that this kind of compounds could be further studied as promising antimicrobial agents. 相似文献
7.
Irena Matulkov Ivana Císaov Ivan Nmec Jan Fbry 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(10):927-933
The X‐ray single‐crystal structure determinations of the chemically related compounds 2‐amino‐1,3,4‐thiadiazolium hydrogen oxalate, C2H4N3S+·C2HO4−, (I), 2‐amino‐1,3,4‐thiadiazole–succinic acid (1/2), C2H3N3S·2C4H6O4, (II), 2‐amino‐1,3,4‐thiadiazole–glutaric acid (1/1), C2H3N3S·C5H8O4, (III), and 2‐amino‐1,3,4‐thiadiazole–adipic acid (1/1), C2H3N3S·C6H10O4, (IV), are reported and their hydrogen‐bonding patterns are compared. The hydrogen bonds are of the types N—H...O or O—H...N and are of moderate strength. In some cases, weak C—H...O interactions are also present. Compound (II) differs from the others not only in the molar ratio of base and acid (1:2), but also in its hydrogen‐bonding pattern, which is based on chain motifs. In (I), (III) and (IV), the most prominent feature is the presence of an R22(8) graph‐set motif formed by N—H...O and O—H...N hydrogen bonds, which are present in all structures except for (I), where only a pair of N—H...O hydrogen bonds is present, in agreement with the greater acidity of oxalic acid. There are nonbonding S...O interactions present in all four structures. The difference electron‐density maps show a lack of electron density about the S atom along the S...O vector. In all four structures, the carboxylic acid H atoms are present in a rare configuration with a C—C—O—H torsion angle of ∼0°. In the structures of (II)–(IV), the C—C—O—H torsion angle of the second carboxylic acid group has the more common value of ∼|180|°. The dicarboxylic acid molecules are situated on crystallographic inversion centres in (II). The Raman and IR spectra of the title compounds are presented and analysed. 相似文献
8.
9.
Ratnadeep S. Joshi Priyanka G. Mandhane Wajid Khan Charansingh H. Gill 《Journal of heterocyclic chemistry》2011,48(4):872-876
A new series of 2‐(p‐tolyloxy)‐3‐(5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazol‐2‐yl)quinoline were synthesized from oxidative cyclization of N′‐((2‐(p‐tolyloxy)quinoline‐3‐yl)methylene)isonicotinohydrazide in DMSO/I2 at reflux condition for 3–4 h. The structures of the new compounds were confirmed by elemental analyses as well as IR, 1H‐NMR, and mass spectral data. All the synthesized compounds were screened for their antibacterial activities against various bacterial strains. Several of these compounds showed potential antibacterial activity. J. Heterocyclic Chem., (2011). 相似文献
10.
Hung‐Te Chang Kuo‐Chen Chiang Fung Fuh Wong Chun‐Sheng Huang Yang‐Ming Liao Wen‐Fa Kuo Shaw‐Bing Won Mou‐Yung Yeh 《Heteroatom Chemistry》2007,18(4):438-442
The synthesis of potential fluorescent active 4‐(5‐aryl‐1,3,4‐oxadiazol‐2‐yl)phenylhydrazine derivatives was accomplished in three steps. The key step was the dehydration cyclization of 1,2‐diacylhydrazines to form the 1,3,4‐oxadiazole ring by use of acetic anhydride/perchloric acid mixture as the dehydrating agent. The sydnone moiety served as the masked hydrazines, which could be demasked by HCl for further application. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:438–442, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20318 相似文献
11.
Wei‐Min Liu You‐Quan Zhu Yi‐Feng Wang Bin Liu Xiao‐Mao Zou Hua‐Zheng Yang 《Journal of heterocyclic chemistry》2007,44(4):967-971
A series of 2‐(3‐(trifluoromethyl)‐5‐(alkoxy)‐1H‐pyrazol‐1‐yl)‐4‐aryloxypyrimidine derivatives were designed and synthesized. The structures of all the title compounds were confirmed by 1H NMR and elementary analysis. These compounds were screened for herbicidal activity against rape and barnyard grass. Compound B13 exhibited moderate herbicidal activity. 相似文献
12.
Abdou O. Abdelhamid Ahmed H. Elghandour Sayed A. Ahmed Yasser H. Zaki 《Journal of heterocyclic chemistry》2006,43(2):249-254
3‐Nitrosoimidazo[1,2‐a]pyridine, 3‐nitrosoimidazo[1,2‐a]pyrimidine, 3‐nitrosoquinoxaline, 2‐nitroso‐4H‐benzo[b]thiazine, 2‐nitroso‐4H‐benzo[b]oxazine, isoxazoles, isoxazolo[3,4‐d]pyridazines and pyrrolo[3,4‐d]isoxazole‐4,6‐dione were synthesized from 2‐chloro‐2‐(hydroximino)‐1‐(4‐methyl‐2‐phenylthiazol‐5‐yl)ethanone and different reagents. Structures of the newly synthesized compounds were confirmed by elemental analysis and spectral data. 相似文献
13.
2‐Formylchromones and 3‐formylchromones as the first materials singly reacted with 2‐amino‐5‐mercapto‐1,3,4‐thiadiazole to give the corresponding Schiff bases, which on cyclocondensation with mercapto‐acetic acid in 1,4‐dioxane yielded target compounds named 4‐oxo‐thiazolidines. The structures of all the synthetic compounds were confirmed by elemental analysis and IR, 1H NMR, LC‐MS (ESI) spectral data. 相似文献
14.
Vanesa Ayala Dulce M. Muoz ngel E. Lozano Jos G. de la Campa Javier de Abajo 《Journal of polymer science. Part A, Polymer chemistry》2006,44(4):1414-1423
A set of new aromatic poly(ether amide)s containing benzimidazole groups and ethylene oxide sequences of different lengths were synthesized and characterized. The new polymers were prepared from two benzimidazole diamines, 2‐(4‐aminophenyl)‐5‐aminobenzimidazole and 2‐(3‐aminophenyl)‐5‐aminobenzimidazole, and various oligo(ethylene oxide)dibenzoyl chlorides. They exhibited good solubility in polar aprotic solvents and glass‐transition temperatures in the range of 125–300 °C (the longer the ethylene oxide spacer was, the lower the glass‐transition temperature was). The new polyamides were essentially amorphous, as observed by X‐ray diffraction measurements and confirmed by differential scanning calorimetry measurements, by means of which no melting endotherm was observed in any case. The decomposition temperatures, as revealed by thermogravimetric analysis in nitrogen, were about 400 °C for all of them, regardless of the length of the ethylene oxide content or the phenylene ring orientation (meta or para) of the diamine moiety. The number of ethylene oxide linkages per repeat unit also determined the water uptake. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1414–1423, 2006 相似文献
15.
5‐Substituted (amine, alkyl, aryl, heterocyclic) 4‐(1,3,4‐thiadiazol‐2‐yl)benzene‐1,3‐ diols were synthesized, and their antifungal properties were examined. The compounds were obtained by the one‐pot reaction of sulfinylbis((2,4‐dihydroxyphenyl)methanethione) with hydrazides or thiosemicarbazides. Their structures were identified from elemental, IR, 1H NMR, and MS spectra analyses. The activities of the derivatives against five phytopathogenic fungi in vitro were measured. Moderate fungicidal effect of the compounds under consideration was found. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:533–540, 2010; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20645 相似文献
16.
Aram M. Knyazyan Karine A. Eliazyan Vergush A. Pivazyan Emma A. Ghazaryan Siranush V. Harutyunyan Aleksandr P. Yengoyan 《Journal of heterocyclic chemistry》2013,50(6):1281-1289
On the base of synthesized 2‐amino and 2‐ethylamino‐(2‐thioxo‐3‐alkyl‐4‐methyl‐3H‐thiazol‐5‐yl)‐[1,3,4]thiadiazoles, their alkyl, acetyl, and alkylacetylamino derivatives are obtained. The alkylation of 2‐ethylamino derivatives can occur at both exo and endo nitrogen atoms of amidine group, and the acetylation takes place exclusively at the exocyclic nitrogen atom. At acetylation of 2‐amino‐[1,3,4]thiadiazoles, only exo substitution is observed. At the further alkylation of these products, a mixture of exo‐ and endo‐substituted forms is obtained. At preliminary screening, the synthesized compounds have shown expressed growth stimulant properties. The activity of the most active derivatives was in the range of 65–100%, compared with that of heteroauxin. 相似文献
17.
Sivaperuman Saravanan Arumugam Nithya Shanmugam Muthusubramanian 《Journal of heterocyclic chemistry》2006,43(1):149-155
The synthesis of a new set of selenadiazoles, 4‐aryl‐5‐(1‐aryl‐2‐methyl‐2‐nitropropyl)‐1,2,3‐selenadiazoles ( 4 ) derived from 2‐[4‐methyl‐4‐nitro‐1,3‐diarylpentylidene]‐1‐hydrazinecarboxamide ( 3 ) has been reported. THF has been found to be the solvent of choice for this reaction. Structural features of 3 and 4 have been analyzed by NMR and X‐ray techniques. 相似文献
18.
Synthesis and Antiviral Bioactivity of Novel 2‐Substituted Methlthio‐5‐(4‐Amino‐2‐Methylpyrimidin‐5‐yl)‐1,3,4‐Thiadiazole Derivatives 下载免费PDF全文
Wen‐Neng Wu An‐Qi Tai Qin Chen Gui‐Ping Ouyang 《Journal of heterocyclic chemistry》2016,53(2):626-632
A series of novel 2‐substituted methlthio‐5‐(4‐amino‐2‐methylpyrimidin‐5‐yl‐)‐1,3,4‐thiadiazole derivatives were synthesized, characterized and evaluated for antiviral activities against tobacco mosaic virus (TMV). The preliminary biological results indicated that most compounds exhibit excellent antiviral activity against TMV in vivo. Among these compounds, compounds 9c , 9i , and 9p displayed the similar curative effect against TMV (EC50 = 287.05–322.47 µg/mL) to that of the commercial agent Ningnanmycin (EC50 = 301.83 µg/mL). In particular, compound 9d demonstrated the best curative effect against TMV (EC50 = 266.21 µg/mL), which was better than that of commercial Ningnanmycin. 相似文献
19.
The paper describes synthesis and antituberculosis activity of α‐[5‐(5‐amino‐1,3,4‐thiadiazol‐2‐yl)‐imidazol‐2‐ylthio]acetic acids ( 5a,b ). The compounds were tested against Mycobacterium tuberculosis strain H37Rv in comparison to rifampicin. Compounds exhibited low activity (MIC ≤ 6.25 μg/ml, % inhibition ≥ 24). 相似文献
20.
Yan Zhang Ren‐Zhong Qiao Peng‐Fei Xu Zi‐Yi Zhang Qin Wang Li‐Min Mao Kai‐Bei Yu 《中国化学会会志》2002,49(3):369-373
Eighteen novel 2‐(1‐aryl‐5‐methyl‐1,2,3‐triazol‐4‐yl)‐1,3,4‐oxadiazole derivatives and two acylhydrazone intermediate compounds were synthesized by various pathways starting from 1‐aryl‐5‐methyl‐1,2,3‐triazol‐4‐formhydrazide ( 1 ). All products were identified by spectroscopic analysis, and 2‐(1‐aryl‐5‐methyl‐1,2,3‐triazol‐4‐yl)‐5‐benzalthio‐1,3,4‐oxadiazole was further validated by X‐ray crystallography. Results from primary antibacterial activity tests indicated that most of the compounds were effective against E. coli, P. aeruginosa, B. subtilis and S. aureus. 相似文献