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41.
In this study, a new, easy and high yield procedure is investigated for the generation of pyrazine containing pyrrolo[2,1-a]isoquinoline derivatives using multicomponent reaction of phthalaldehyde or its derivatives, primary amines, α-haloalketones, electron deficient acetylenic compounds, ammonium acetate and KF/Clinoptilolite nanoparticles (KF/CP NPs) as catalyst in water at room temperature. The reactions of 2-hydroxy phthalaldehyde, primary amines, α-haloketones, electron deficient acetylenic compounds, and ammonium acetate in the presence of KF/CP NPs as catalyst in water at room temperature produce pyrazine derivatives in good yields. Also, in this work, antioxidant ability was studied for a number of prepared compounds employing the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and power of compounds for reducing of ferric ion experiments and evaluating results with synthetic antioxidants (TBHQ and BHT). Comfortable, simple, fast and fresh procedure is the advantages of this study.  相似文献   
42.
A one‐pot synthesis of oxazine derivatives via reaction between activated acetylenic compounds, benzoyl cyanide, and N‐nucleophiles in water as the solvent is described?.  相似文献   
43.
44.
An efficient synthesis of 1,3-oxathiolane-2-imin derivatives is described via one-pot reaction between arylisothiocyanats, asymmetrically substituted oxiranes and catalytic amount of methanol.The mild reaction conditions and high yields of the products exhibit the good synthetic advantage of this method.  相似文献   
45.
An efficient synthesis of functionalized 1,3‐dienes via one‐pot reactions between dialkyl acetylenedicarboxylates?, 1,3‐dicarbonyl compounds and secondary amines in ?water as the solvent is described. The mild reaction condition high yields and the ?new products are advantages of our method.  相似文献   
46.
An efficient diastereoselective synthesis of 7-ethyl 5,6-dialkyl 7H-[1,3]thiazolo[2,3-b][1,3]oxazin-5,6, 7-tricarboxylates and 2-ethyl 3,4-dialkyl 2H-[1,3]oxazino [2,3-b][1,3]benzothiazole-2,3,4-tricarboxylates via reaction of thiazole and benzothiazole with dialkyl acetylenedicarboxylates in the presence of ethyl pyruvate is described.  相似文献   
47.
A novel class of benzofuran derivatives is prepared from the isocyanide-based MCR, euparin and aldehydes in the presence of ZnO-nanorods as a catalyst in excellent yields at room temperature under solvent-free conditions as a green reaction medium. Also, the antioxidant activities of some synthesised compounds such as 4a, 4b, 10a and 10b were evaluated by DPPH radical scavenging and ferric reduction activity potential (FRAP) assays. Compound 10b, was shown moderate radical scavenging activity and very good reducing activity compared to standards (BHT and TBHQ).  相似文献   
48.
Molecular Diversity - In this research we investigated the preparation of new (5Z, 8Z)-7H-pyrido[2,3-d]azepine derivatives in high yields via multicomponent reaction of isatins, alkyl bromides,...  相似文献   
49.
In this research, a novel procedure for the synthesis of pyrazole derivatives in excellent yields was studied using catalyst-free multicomponent reaction of isoquinoline, activated acetylenic compounds, alkyl bromides, triphenylphosphine and hydrazine in water under ultrasonic irradiation at room temperature. The advantages of this procedure than to reported methods are short time of reaction, high yields of product, easy separation of product, clean mixture of reaction and green media for performing reaction. In addition, because of having pyrazole and isoquinoline core in the synthesized compounds, in this research, antioxidant activity of some synthesized compounds was investigated.  相似文献   
50.
Ionic liquids such as 1,3‐dialkylimidazolium bromides make excellent solvents for synthesis of α‐aminophosphonates from aldehydes, amines, and phosphites. The ionic liquids are successfully regenerated and reused. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:625–629, 2011; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20724  相似文献   
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