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探讨了在微波加热条件下,芳香醛、取代苯乙酮和尿素的三组分反应在N,N-二甲基甲酰胺(DMF)中制得4,6-二芳基-3,4-二氢嘧啶-2(1H)-酮类化合物,收率为68%~84%.若在反应体系中加入三甲基氯硅烷,该三组分反应则高产率(66%~87%)地生成相应的脱氢产物4,6-二芳基嘧啶-2(1H)-酮类化合物.该反应具有反应条件温和、产物收率高、操作方便等优点,为4,6-二芳基-嘧啶-2(1H)-酮类药物中间体的合成提供了一条全新的路线. 相似文献
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《Journal of heterocyclic chemistry》2018,55(7):1579-1588
In contrast to target‐oriented synthesis that aims to access precise regions of chemistry, diversity‐oriented synthesis via multicomponent synthesis populates chemical space broadly with small molecules having diverse structures. This study has achieved the diversity‐oriented synthesis of novel imidazo[4′,5′:4,5]benzo[e][1,4]thiazepinones ( 4 ) and benzo[d]imidazolyl thiazolidinones ( 5 ) controlled by the nature of substitution effect of the reaction component. The one‐pot reaction of benzimidazole 1 , aromatic aldehyde 2 , and mercaptoacetic acid 3 leads to the formation of imidazo[4′,5′:4,5]benzo[e][1,4]thiazepinones ( 4 ) with electron‐donating groups as substitution on aromatic aldehyde while electron‐withdrawing substitutions produced benzo[d]imidazolyl thiazolidinones ( 5 ). The title compounds ( 4 ) and ( 5 ) were evaluated for their antimicrobial and anti‐inflammatory activities. 相似文献
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We have developed highly efficient, one‐pot three component reaction of 5‐amino‐uracil and aromatic aldehydes with thioglycolic acid for the synthesis of N‐uracil‐thiazolidinones in excellent yields. The same products were also prepared by the reaction of Schiff bases of 5‐amino‐uracil with thioglycolic acid. In addition, benzylation of thiazolidinone derivatives and Schiff bases by using benzyl chloride was investigated. The results obtained from elemental microanalysis and different spectral data are in agreement with the assigned structures. 相似文献
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Synthesis of the title compounds was achieved using the anils 2a , 2b , 2c , 2d , 2e and 5a , 5b , 5c derived from the 4‐aminopyrazole 1 as starting materials. These compounds were allowed to react with mercaptoacetic acid in boiling dry benzene to afford the corresponding thiazolidinones and spiro‐thiazolidinones 3a , 3b , 3c , 3d , 3e and 6a , 6b , 6c , respectively. Pictet—Spengler reaction of the 4‐aminopyrazole hydrochloride 7 with aromatic aldehydes and cyclic ketones resulted in the formation of new pyrazolo[4,3‐e]pyrrolo[1,2‐a]pyrazines 8a , 8b , 8c , 8d , 8e and 9a , 9b , respectively. Other derivatives of pyrazolo pyrrolopyrazines 10 and 11 were obtained via the reaction of the amino derivative 1 with 1,1′‐carbonyldiimidazol and CS2, respectively. J. Heterocyclic Chem., (2011). 相似文献
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Himani N. Chopde Ramakanth Pagadala Jyotsna S. Meshram Venkateshwarlu Jetti 《Journal of heterocyclic chemistry》2011,48(6):1323-1328
5‐((3‐Aminophenyl)diazenyl)quinolin‐8‐ol ( 1 ) was synthesized by diazotization reaction and coupled with 8‐hydroxyquinoline moiety. This amine on facile condensation with aromatic aldehydes in presence of glacial acetic acid and ethanol affords anils ( 2 ). These anils on cyclocondensation reaction with thioglycolic acid (i.e., mercaptoacetic acid) yield the titled compound ( 3 ). The structure of the newly synthesized anils ( 2 ) and thiazolidinones ( 3 ) has been confirmed by elemental analysis and spectral analysis. The titled compounds have been screened against different bacterial and fungal strains. J. Heterocyclic Chem., (2011). 相似文献
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Venkatraman Ramanujam Cyril Charlier Ad Bax 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(43):15453-15456
In aqueous solution, many biochemical reaction pathways involve reaction of an aldehyde with an amine, which progresses through generally unstable, hydrated and dehydrated, Schiff base intermediates that often are unobservable by conventional NMR. There are 4 states in the relevant equilibrium: 1) gem‐diol, 2) aldehyde, 3) hemiaminal, and 4) Schiff base. For the reaction between protein amino groups and DOPAL, a highly toxic metabolite of dopamine, the 1H resonances of both the hemiaminal and the dehydrated Schiff base can be observed by CEST NMR, even when their populations fall below 0.1 %. CEST NMR reveals the quantitative exchange kinetics between reactants and Schiff base intermediates, explaining why the Schiff base NMR signals are rarely observed. The reactivity of DOPAL with Nα‐amino groups is greater than with lysine N?‐amines and, in the presence of O2, both types of Schiff base DOPAL–peptide intermediates rapidly react with free DOPAL to irreversibly form dicatechol pyrrole adducts. 相似文献
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The reaction of 1,4,5,6‐tetrahydro‐6‐pyridazinone‐3‐carboxylic acid hydrazides ( 1 ) with aromatic aldehydes afforded 1,4,5,6‐tetrahydro‐6‐pyridazinone‐3‐carbonyl aromatic aldehyde hydrazones ( 2a‐2g ). Heterocyclic derivatives linked 1,3,4‐oxadiazole obtained by cyclocondensation of 2a‐2g with acetic anhydride in absolute ethanol, and 2a‐2g cyclized with mercaptoacetic acid in DMF in the presence of anhydrous ZnCl2 afforded the 1,3‐thiazolidinone derivatives. The structures of the new compounds were established by elemental analyses, IR, 1H NMR and MS spectral data. 相似文献
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Wafaa S. Hamama Moustafa A. Gouda Marwa H. Badr Hanafi H. Zoorob 《Journal of heterocyclic chemistry》2013,50(4):787-794
Annulations of 2‐amino‐1,3,4‐thiadiazole ( 1 ) with α,β‐unsaturated carbonyl compounds 2 , 5 , and 9 afforded thiadiazolo[3,2‐a]pyrimidin 3 , benzamide 7 , and bis‐pyrazole derivative 11 . Cyclization of benzamide 7 with POCl3 gave binary imidazole derivative 8 . Moreover, alkylation of 1 with 2‐bromo‐1‐(2H‐chromen‐3‐yl) ethanone ( 9 ) followed by cyclization gave imidazo[2,1‐b]‐1,3,4‐thiadiazole derivative 15 . Multicomponent reaction of 1 with heterocyclic and/or aromatic aldehyde and thioglycolic acid afforded the corresponding thiazolidinones 17 and 19 . Finally, a one‐pot synthesis of 1 with isatin and thiosemicarbazide furnished the spirotriazole 20 . The newly synthesized compounds were evaluated as antitumor agents. 相似文献
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A set of structurally varied indano[1,2‐d][1,3]oxazines and thiazines, which are new ring systems, were prepared by ring‐closure reactions of amino alcohols 4–6. The reactions of cis‐ and trans‐1‐amino‐ and cis‐ 1‐benzylamino‐2‐hydroxymethylindane (4–6) with 1 equivalent of an aromatic aldehyde in methanol at room temperature resulted in three‐component equilibria (15a‐g), or a Schiff base (16), or a ring‐closure product alone (17a‐c), respectively, depending on the substitution or configuration of the starting amino alcohol. The ring‐chain tautomeric equilibria can be described by an equation of Hammett type. 相似文献
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Synthesis,Dissociation Constants,and Some Pharmacological Properties of Schiff Base Hydrazones and their Cyclization to 1,3‐Thiazolidin‐4‐one Derivatives
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Ł. Popiołek A. Chodkowska A. Tryka K. Pawłowski M. Kiełczykowska J. Kocot M. Wujec E. Jagiełło‐Wójtowicz 《Journal of heterocyclic chemistry》2015,52(5):1506-1512
This study presents the synthesis, dissociation constants, and pharmacological properties of Schiff base hydrazones. The derivatives were synthesized by the condensation reaction of carboxylic acid hydrazides containing 1,2,4‐triazole system with various aldehydes. The new derivatives of 1,3‐thiazolidin‐4‐one were prepared by the cyclization reaction of Schiff base hydrazones with the mercaptoacetic acid in the presence of 1,4‐dioxane. The structure of all obtained compounds was confirmed by means of 1H NMR and 13C NMR spectra. The dissociation constants were determined using spectrophotometric method. The effects of four synthesized Schiff base hydrazones 6 , 7 , 11 and 12 on the central nervous system of mice in behavioral tests were examined. 相似文献
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A series of novel 2‐aryl‐3‐(9‐alkylcarbazol‐3‐yl)thiazolidin‐4‐ones were synthesized by one‐pot three‐component reactions of 3‐amino‐9‐alkylcarbazoles, aromatic aldehydes, and 2‐mercaptoacetic acid by using dicyclohexylcarbodiimide (DCC) as a cyclizing agent in dry diethyl ether at room temperature. This protocol has advantages of mild condition, short reaction time, high yield, and simple work‐up procedure. 相似文献