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1.
An Efficient Synthesis of Novel 2‐(5‐indolyl)‐1H‐benzimidazole Derivatives and Evaluation of Their Antimicrobial Activities 下载免费PDF全文
Venugopal Soodamani Divyesh Patel Devanna Nayakanti Ramanatham Josyula 《Journal of heterocyclic chemistry》2015,52(5):1457-1466
In this paper, we report the synthesis of novel 2‐(5‐indolyl)‐1H‐benzimidazole derivatives. The methodology involves the Sonogashira reaction of 4‐(1H‐benzimidazol‐2‐yl)‐2‐bromo‐N,N‐dimethylaniline ( 3 ) with variety of terminal alkynes to get corresponding novel 4‐(1H‐benzimidazol‐2‐yl)‐2‐alkynyl‐N,N‐dimethylaniline derivatives ( 4 ). These compounds on iodocyclization afforded novel iodoindolylbenzimidazole derivatives ( 5 ). The resulting compounds were functionalized further via palladium‐mediated carbon–carbon bond formation for generating novel structurally diversified heterocyclic compounds. All these newly synthesized compounds were evaluated for antimicrobial activity. 相似文献
2.
Synthesis and Biological Activity of Ethyl 4‐Alkyl‐2‐(2‐(substituted phenoxy)acetamido)thiazole‐5‐carboxylate 下载免费PDF全文
Wenyan Mo Yanxia Shi Junbo He Baoju Li Hao Peng Hongwu He 《Journal of heterocyclic chemistry》2016,53(1):183-187
A series of novel ethyl 4‐(methyl or trifluoromethyl)‐2‐(2‐(substituted phenoxy)acetamido)thiazole‐5‐carboxylates 7a , 7b , 7c , 7d , 7e and 8f , 8g , 8h , 8i , 8j , 8k , 8l , 8m , 8n , 8o , 8p , 8q , 8r were synthesized, and their structures were confirmed by IR, 1H‐NMR, MS spectra and elemental analysis. The results of preliminary bioassays show that some of the title compounds exhibit moderate to good herbicidal activities. Compared with the fluorine free compounds 7a , 7b , and 7e , the compounds bearing fluorine 8g , 8j , and 8q showed higher herbicidal activities with 70–100% inhibition against Capsella bursa‐pastoris, Amaranthus restroflexus, and Eclipta prostrata at the dosage of 150 g/ha, which indicated that the trifluoromethyl on the thiazole ring was beneficial for the herbicidal activity. Furthermore, compounds 8f , 8g , 8h , 8i , 8j , 8k , 8l , 8m , 8n , 8o , 8p , 8q , 8r were tested for fungicidal activity against Pseudoperonospora cubensis at 500 µg/mL. Compounds 8f and 8q showed the best fungicidal activity with more than 80% inhibition. 相似文献
3.
K. Srinivasulu B. Hari Babu K. Suresh Kumar C. Bhupendra Reddy C. Naga Raju D. Rooba 《Journal of heterocyclic chemistry》2008,45(3):751-757
Synthesis of 6‐bromo‐2‐(substituted)‐3‐(1‐phenyl‐ethyl)‐3,4‐dihydro‐1H‐isophosphinoline 2‐chalco‐genides derivatives (6) were synthesized from 2‐[(1‐phenylethylamino)methyl]‐4‐bromophenol ( 1 ) by reaction with aryl/alkyl phosphoro dichloridates ( 2 ) in the presence of triethylamine at 55°C to 60°C to obtained the title compounds ( 6a‐g ). The title compounds ( 6h‐j ), were prepared via intermediate route. Few other title compounds ( 8a‐c ) were accomplished through a two step synthetic route involving 1 with dichlorophenyl phosphine ( 2a ) and dichloroethyl phosphine ( 2a,b ) in the presence of triethylamine in dry toluene under N2 atmosphere to form the corresponding trivalent phosphorus intermediate (7) . In the second step they were further converted to the corresponding chalcogenides 8a‐c by reaction with hydrogen peroxide, sulfur and selenium respectively. They exhibited significant antibacterial, fungal and insecticidal activity. 相似文献
4.
E. Vishnu Vardhan Reddy J. Ramanatham N. Devanna K. Srinivasa Reddy D. Rajender 《Journal of heterocyclic chemistry》2013,50(Z1):E221-E227
Novel 2‐(substituted)‐5‐(1‐methyl‐1H‐indazol‐3‐yl)‐oxazoles ( 13 ) were synthesized in moderate yields, from 1‐methyl‐1H‐Indazole 3‐carboxylic acid ( 1 ), by converting it into a variety of amides ( 12 ) and further its heterocyclization. The structures of all the compounds have been elucidated on the basis of IR, 1H‐NMR, and HRMS. 相似文献
5.
Andrei Y. Bochkov Mikhail M. Krayushkin Vladimir N. Yarovenko Valery A. Barachevsky Irina P. Beletskaya Valery F. Traven 《Journal of heterocyclic chemistry》2013,50(4):891-898
Novel unsymmetrical di(thienyl)maleic acid anhydride, including coumarin moiety, has been designed and synthesized. Its photochromism study and fatigue resistance estimation are reported. Microwave‐assisted procedure has been successfully used for synthesis of 3‐(5‐methylthiophen‐2‐yl)coumarins. 相似文献
6.
《Journal of heterocyclic chemistry》2017,54(3):2003-2011
A simple facile “one‐pot” synthesis of 5‐(4‐chlorophenyl)‐7‐(3,4‐dimethyl phenyl)‐2‐oxo‐2H‐pyrano[2,3‐b]pyridine derivatives via three‐component reaction of chalcone, ethyl‐2‐substituted acetate, and ammonium acetate under ultrasonic irradiation and grinding tools. The newly synthesized compounds were evaluated for their antibacterial activity against ATCC 25923, ATCC 10987, ATCC 274, and SM514. All the synthesized compounds have been characterized on the basis of their elemental analyses and spectral data. 相似文献
7.
Jayaram Reddy Komsani Sreenivas Avula Satish Koppireddi Pranay Kumar Koochana Murty USN Rambabu Yadla 《Journal of heterocyclic chemistry》2015,52(3):764-772
A convenient synthesis of a new series of N‐aryl‐5‐(pyridin‐3‐yl)‐1H/3H‐1,2,3‐triazole‐4‐carbonitriles and alkyl N‐aryl‐5‐(pyridin‐3‐yl)‐1H/3H‐1,2,3‐triazole‐4‐carboxylic acid esters is reported. The newly synthesized 5‐(pyridin‐3‐yl)‐1,2,3‐triazole derivatives are evaluated for their antibacterial and antifungal activity. Some of these triazole derivatives have exhibited moderate antimicrobial activity. 相似文献
8.
《Journal of heterocyclic chemistry》2017,54(3):1751-1756
A novel series of pyrazole carboxamide derivatives had been designed, synthesized and some of them exhibited good nematocidal activity. 相似文献
9.
Monika Janjić Rok Prebil Uroš Grošelj David Kralj Črt Malavašič Amalija Golobič Katarina Stare Georg Dahmann Branko Stanovnik Jurij Svete 《Helvetica chimica acta》2011,94(9):1703-1717
A four‐step synthesis of 1‐substituted 5‐(2‐aminophenyl)‐1H‐pyrazoles 5 as a novel type of histamine analogs and versatile building blocks for further transformations was developed. The synthesis starts from commercially available 2‐nitroacetophenone ( 12 ), which is converted into the enamino ketone 13 as the key intermediate. Cyclization of the key intermediate 13 with monosubstituted hydrazines 14a – 14l afforded the 5‐(2‐nitrophenyl)‐1H‐pyrazoles 17a – 17l . Finally, catalytic hydrogenation of the nitro compounds 17a, 17c – 17e , and 17g – 17j furnished the title compounds 5a, 5c – 5e , and 5g – 5j , respectively, in good yields. As demonstrated by some further transformations, additional functionalization of compounds 17 and 5 is feasible, either by electrophilic substitution at C(4) of the pyrazole ring, or at the NH2 group. 相似文献
10.
Asha V. Chate Dattatraya S. Ghotekar Sunil S. Bhagat Charansingh H. Gill 《Journal of heterocyclic chemistry》2013,50(1):149-154
An efficiently synthesis of chromones via cyclodehydration of corresponding 1‐(2‐hydroxyphenyl)‐3‐(pyridine‐3‐yl)propane‐1,3‐dione is described under ultrasound irradiation. A series of novel 2‐(pyridine‐3‐yl)‐4H‐chromen‐4‐one derivatives was confirmed on the basis of 1H‐NMR, mass, IR spectral data, and elemental analysis. The synthesized compounds were evaluated for their antibacterial and antifungal activities. Most of the compounds were found to be comparable potent than the reference standard drugs. Utilization of ultrasound irradiation, simple reaction conditions, isolation, and purification makes this manipulation very interesting from an economic and environmental perspective. 相似文献
11.
《Journal of heterocyclic chemistry》2018,55(3):743-749
A series of 2‐substitued‐(3‐pyridyl)‐quinazolinone derivatives were synthesized, characterized, and evaluated for bacteriostatic activity against three species of phytopathogenic bacteria (Xanthomonas oryzae pv. oryzae, Xoo, Ralstonia solanacearum, and Xanthomonas axonopodis pv. citri, Xac). Biological evaluation showed that compounds 4b , 4g , 4h , 4l , and 4m exhibited higher antibacterial activity than bismerthiazol, the positive control, under conditions. In particular, compounds 4l and 4m exhibited significant bacteriostatic activity against Xac. 相似文献
12.
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
13.
Wael A. El‐Sayed Mohamed A. Metwally Doaa S. Nada Asem A. Mohamed Adel A.‐H. Abdel‐Rahman 《Journal of heterocyclic chemistry》2013,50(2):194-201
New substituted 5‐(pyridine‐3‐yl)‐1,3,4‐thiadiazoles, their sugar hydrazones and acyclic C‐nucleoside analogs as well as the corresponding thioglycoside derivatives were synthesized. The synthesized compounds were tested for their antimicrobial activity against Escherichia coli, Bacillus subtilis, Staph aureus, Aspergillus niger, and Candida albicans The obtained results indicated that most of tested compounds exhibited moderate to high antimicrobial activity while few compounds were found to exhibit little or no activity against the tested microorganisms. 相似文献
14.
《Journal of heterocyclic chemistry》2017,54(2):1506-1513
A series of 2‐substituted phenoxy‐N‐(4‐substituted phenyl‐5‐(1H‐1,2,4‐triazol‐1‐yl)thiazole‐2‐yl)acetamide derivatives 8a , 8b , 8c , 8d , 8e , 8f , 8g , 8h , 8i , 8j , 8k , 8l , 8m , 8n , 8o , 8p , 8q , 8r , 8s , 8t was synthesized by the reaction of phenoxyacetyl chloride 7 with intermediate 4‐substituted phenyl‐5‐(1H‐1,2,4‐triazol‐1‐yl)thiazol‐2‐amine 5 . Their structures were confirmed by 1H NMR, 13C NMR, MS, IR, and elemental analyses. The synthesized compounds were also screened for their antimicrobial activity against three types of plant fungi (Gibberella zeae , Phytophthora infestans , and Paralepetopsis sasakii ) and two kinds of bacteria [Xanthomonas oryzae pv. oryzae (Xoo ) and Xanthomonas axonopodis pv. citri (Xac )] showing promising results. In particular, 8b , 8f , 8g , and 8h exhibited excellent antibacterial activity against Xoo , with 50% effective concentration (EC50) values of 35.2, 80.1, 62.5, and 82.1 µg/mL, respectively, which are superior to the commercial antibacterial agent bismerthiazol (89.9 µg/mL). The preliminary structure–activity relationship studies of these compounds are also briefly described. 相似文献
15.
An Efficient Synthesis of 3‐(3‐benzyl‐2‐(phenylimino)‐2,3‐dihydrothiazol‐4‐yl)‐6‐methyl‐4‐(2‐oxo‐2‐phenylethoxy)‐3,4‐dihydro‐2H‐pyran‐2‐one Derivatives via Multi‐Component Approach 下载免费PDF全文
An easy, highly efficient and a new convenient one‐pot, two‐step approach to the synthesis of 3‐(3‐benzyl‐2‐(phenylimino)‐2,3‐dihydrothiazol‐4‐yl)‐6‐methyl‐4‐(2‐oxo‐2‐phenylethoxy)‐3,4‐dihydro‐2H‐pyran‐2‐one is described. These compounds were synthesized from 3‐(3‐benzyl‐2‐(phenylimino)‐2,3‐dihydrothiazol‐4‐yl)‐4‐hydroxy‐6‐methyl‐3,4‐dihydro‐2H‐pyran‐2‐one and α‐bromoketones in good yields. The compounds 4 were synthesized by a multi‐component reaction between 1 , 2 , and 3 and the prominent features of this protocol are mild reaction conditions, operation simplicity, and good to high yields of products. 相似文献
16.
A rapid microwave‐accelerated thionation of some 3‐substitued isocoumarins to corresponding 1‐thio‐isocoumarins was achieved employing Lawesson's reagent under solventless conditions. 相似文献
17.
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
18.
19.
Synthesis of Novel 3‐(3‐(5‐Methylisoxazol‐3‐yl)‐7H‐[1,2,4]Triazolo [3,4‐b][1,3,4]Thiadiazin‐6‐yl)‐2H‐Chromen‐2‐Ones 下载免费PDF全文
A novel series of coumarin substituted triazolo‐thiadiazine derivatives were designed and synthesized by using 5‐methyl isoxazole‐3‐carboxylic acid ( 1 ), thiocarbohydrazide ( 2 ), and various substituted 3‐(2‐bromo acetyl) coumarins ( 4a , 4b , 4c , 4e , 4d , 4f , 4g , 4h , 4i , 4j ). Fusion of 5‐methyl isoxazole‐3‐carboxylic acid with thiocarbohydrazide resulted in the formation of the intermediate 4‐amino‐5‐(5‐methylisoxazol‐3‐yl)‐4H‐1,2,4‐triazole‐3‐thiol ( 3 ). This intermediate on further reaction with substituted 3‐(2‐bromo acetyl) coumarins under simple reaction conditions formed the title products 3‐(3‐(5‐methylisoxazol‐3‐yl)‐7H‐[1,2,4]triazolo[3,4‐b][1,3,4]thiadiazin‐6‐yl‐2H‐chromen‐2‐ones ( 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h , 5i , 5j ) in good to excellent yields. All the synthesized compounds were well characterized by physical, analytical, and spectroscopic techniques. 相似文献
20.
Florence Popowycz Sandrine Gerber‐Lemaire Catherine Schütz Pierre Vogel 《Helvetica chimica acta》2004,87(4):800-810
New 2‐(aminomethyl)‐5‐(hydroxymethyl)pyrrolidine‐3,4‐diol derivatives were synthesized from (5S)‐5‐[(trityloxy)methyl]pyrrolidin‐2‐one ( 6 ) (Schemes 1 and 2) and their inhibitory activities toward 25 glycosidases assayed (Table). The influence of the configuration of the pyrrolidine ring on glycosidase inhibition was evaluated. (2R,3R,4S,5R)‐2‐[(benzylamino)methyl]‐5‐(hydroxymethyl)pyrrolidine‐3,4‐diol ((+)‐ 21 ) was found to be a good and selective inhibitor of α‐mannosidase from jack bean (Ki=1.2 μM ) and from almond (Ki=1.0 μM ). Selectivity was lost for the non‐benzylated derivative (2R,3R,4S,5R)‐2‐(aminomethyl)‐5‐(hydroxymethyl)pyrrolidine‐3,4‐diol ((+)‐ 22 ) which inhibited α‐galactosidases, β‐galactosidases, β‐glucosidases, and α‐N‐acetylgalactosaminidase as well. 相似文献