- Eco-efficiency and scalable synthesis of bisamides in deep eutectic solvent
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Solvents define a major part of the environmental performance of processes in chemical industry and also impact on cost, safety and health issues. In order to minimize the environmental impact resulting from the use of volatile organic solvents in chemica
- Azizi, Najmedin,Alipour, Masoumeh
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- An efficient synthesis of 4,5-diaryl-3,4-dihydropyrimidin-2(1: H)-one via a cesium carbonate-promoted direct condensation of 1-aryl-2-propanone with 1,1'-(arylmethylene)diurea
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An efficient method for the synthesis of 4,5-diaryl-3,4-dihydropyrimidin-2(1H)-one by using 1,1'-(arylmethylene)diurea and 1-aryl-2-propanone as substrates was developed. The reactions proceeded efficiently in the presence of Cs2CO3 to give the desired pr
- Deng, Wei,Guo, Yi-Cong,Rao, Weidong,Shen, Zhi-Liang,Song, Xuan-Di,Xu, Haiyan
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- Highly Efficient Synthesis of Substituted 3,4-Dihydropyrimidin-2-(1H)-ones (DHPMs) Catalyzed by Hf(OTf)4: Mechanistic insights into reaction pathways under metal Lewis acid catalysis and solvent-free conditions
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In our studies on the catalytic activity of Group IVB transition metal Lewis acids, Hf(OTf)4 was identified as a highly potent catalyst for”one-pot, three-component” Biginelli reaction. More importantly, it was found that solvent-free conditions, in contrast to solvent-based conditions, could dramatically promote the Hf(OTf)4-catalyzed formation of 3,4-dihydro-pyrimidin-2-(1H)-ones. To provide a mechanistic explanation, we closely examined the catalytic effects of Hf(OTf)4 on all three potential reaction pathways in both “sequential bimolecular condensations” and “one-pot, three-component” manners. The experimental results showed that the synergistic effects of solvent-free conditions and Hf(OTf)4 catalysis not only drastically accelerate Biginelli reaction by enhancing the imine route and activating the enamine route but also avoid the formation of Knoevenagel adduct, which may lead to an undesired byproduct. In addition, 1H-MMR tracing of the H-D exchange reaction of methyl acetoacetate in MeOH-d4 indicated that Hf(IV) cation may significantly accelerate ketone-enol tautomerization and activate the β-ketone moiety, thereby contributing to the overall reaction rate.
- Kong, Rui,Han, Shuai-Bo,Wei, Jing-Ying,Peng, Xiao-Chong,Xie, Zhen-Biao,Gong, Shan-Shan,Sun, Qi
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- Biginelli reaction via bis-ureide intermediate in low melting mixture
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This paper deals with the study of mechanism of the Biginelli reaction using low melting mixture as solvent and catalyst. The catalytic effect of low melting mixture and the reaction mechanism is discussed on the basis of nuclear magnetic resonance (NMR)
- Mahajan, Hitesh,Jamwal, Babita,Paul, Satya
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p. 585 - 593
(2019/09/30)
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- One pot preparations N,N′-alkylidene bisamide derivatives catalyzed by Nano-TiCL4.SiO2 with antimicrobial studies of some products
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Nano-TiCl4.SiO2 has been introduced to be an extremely efficient catalyst for the preparation of N,N′-alkylidene bisamides from various aldehydes and amides under mild conditions. We synthesized this solid Lewis acid catalyst by the
- Khabnadideh, Soghra,Zomorodian, Kamiar,Mirjalili, Bi Bi Fatemeh,Izadi, Elham,Zamani, Leila
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p. 3034 - 3038
(2016/11/17)
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- Molybdate and silica sulfuric acids as heterogeneous alternatives for synthesis of gem-bisamides and bisurides from aldehydes and amides, carbamates, nitriles or urea
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Molybdate sulfuric acid (MSA) and silica sulfuric acid (SSA) has been prepared and used as efficient solid catalysts for the synthesis of gem-bisamides and bisurides via the one-pot three-component reaction of two moles of amides, nitriles, carbamates or urea with aldehydes. The catalytic efficiency of SSA, MSA, or H2SO4 98% per H+ sites as turnover number (TON), turnover frequency (TOF), and atomic economy (AE) was calculated and compared for quantitative evaluation of catalysts. The AE, TON, and TOF factors show the superiority of the SSA versus MSA and H 2SO4. Short reaction times, simple work-up, chemoselectivity, low loading, and reusability of solid acid catalysts are extra advantages than current methods reported in the literature with corrosive acidic catalysts.
- Tamaddon, Fatemeh,Kargar-Shooroki, Hossein,Jafari, Abbas Ali
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- Synthesis and in vitro evaluation of N-Aryl pyrido-quinazolines derivatives as potent epidermal growth factor receptor inhibitors
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A series of pyrido-quinazolines have been synthesised, characterized, and tested for their in vitro epidermal growth factor receptor (EGFR) tyrosine kinase inhibitory activity. The compounds were prepared from Alkylideno/arylideno-bis-ureas. Their final structure of the compounds was elucidated on the basis of spectral studies (IR, 1H NMR, FT-IR, and EI-MS). The cellular EGFR internalization response of selected compounds was evaluated using HeLa cells. Most of the synthesized compounds displayed potent EGFR-TK inhibitory activity and structurally halogenated derivatives had a pronounced effect in inhibiting EGFR internalization.
- Singh, Vinay K.,Sharma, Himanshu,Singh, Sanjay K.,Gangwar, Lakshmi
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p. 119 - 124
(2013/07/26)
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- Tandem synthesis of N,N'-alkylidenebisamides promoted by nano-SnCl4.SiO2
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A highly efficient procedure for the preparation of N,N'- alkylidenebisamides in the presence of nano-SnCl4.SiO2 as a catalysis described. N,N'-alkylidenebisamides have been prepared via condensation reaction of various aldehydes and amides. All of the re
- Mirjalili, Bibi Fatemeh,Mirhoseini, Mohammad Ali
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p. 1481 - 1486
(2014/04/03)
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- The three-component biginelli reaction: A combined experimental and theoretical mechanistic investigation
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Biginelli reactions have been monitored by direct infusion electrospray ionization mass spectrometry (ESI-MS) and key cationic intermediates involved in this three-component reaction have been intercepted and further characterized by tandem MS experiments
- De Souza, Rodrigo O.M.A.,Da Penha, Eduardo T.,Milagre, Humberto M.S.,Garden, Simon J.,Esteves, Pierre M.,Eberlin, Marcos N.,Antunes, Octavio A.C.
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supporting information; body text
p. 9799 - 9804
(2010/05/19)
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- An investigation leading to preparation of tetrahydro-quinazoline derivatives involving ureidoalkylation and α-amidoalkylation reactions
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Reaction of an aldehyde with excess equivalent of urea in ethanol affords alkylideno/arylideno-bis-ureas 1 which on condensation with p-aminophenol in acidic medium cyclised to 4-aralkyl-6-hydroxy-2-oxo-1,2,3,4- tetrahydroquinazolines 2. Reaction of 2 with arylamidoalcohols in concentrated H2SO4 results in 4-arylkyl-7-arylamido/imidoalkyl-6- hydroxy-2-oxo-1,2,3,4-tetrahydroquinazolines 3, Compounds 3 have been evaluated for their effect on central nervous system (CNS) and cardiovascular system (CVS).
- Pandey,Mukesh,Kumar, Anilesh,Trivedi, Noopur
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experimental part
p. 1910 - 1914
(2009/05/30)
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- Synthesis, antibacterial and antifungal activity of some new pyrido quinazolones
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Alkylideno/arylideno bis ureas 1 synthesized by ureido-alkylation in the presence of alcohols-which on treatment with p-aminobenzoic acid results in 4-aryl-6-carboxylato-1,2,3,4-tetrahydroquinazolines 2. Reaction of 2 with benzoin in presence of polyphosphoric acid yields 4-aryl-8,9-diphenyl-1,4 dihydro-3H, 7-oxo-1,3-diaza anthracene-2,6-dione 3. Condensation of 3 with aromatic primary amine affords N-aryl-8,9-diphenyl (-2-oxopyrido [g]-4-aryl-2-oxo-1,3-dihydro quinazolines 4. The new compound 4 has been screened for their antibacterial and antifungal activities.
- Singh,Pandey
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p. 2745 - 2748
(2007/10/03)
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- Synthesis and pharmacological study of novel pyrido-quinazolone analogues as anti-fungal, antibacterial, and anticancer agents
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A versatile method for novel pyrido-quinazolones was described here and tested for anti-fungal, antibacterial, and anticancerous activities. These synthesized compounds were characterized on the basis of spectroscopic techniques and evaluated for specific radiopharmaceuticals. Preliminary radiolabeling results with 99mTc and biological evaluation studies showed promising results for further evaluation in vivo. The efficiency of labeling was more than 98% and complexes were stable for about 18 h at 25 °C in the presence of serum.
- Tiwari, Anjani K.,Mishra,Bajpai, Aruna,Mishra, Pushpa,Sharma,Pandey,Singh, Vinay Kumar
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p. 4581 - 4585
(2007/10/03)
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- UREAS IN ORGANIC SYNTHESIS X. SYNTHESIS OF PERHYDRO-2-PHENYL-1,3,5-TRIAZINE-4,6-DIONE AND 1,3,5-TRI(METHYLTHIOMETHYL)-1,3,5-TRIAZINE-2,4,6-TRIONE BY THE REACTION OF BENZALDEHYDE WITH UREA OR FROM BENZYLIDENEBISUREA BY THE ACTION OF DIMETHYL SULFOXIDE
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Benzaldehyde and urea are converted by the action of DMSO at 185 deg C into benzylidenbisurea and 1,3,5-tri(methylthiomethyl)-1,3,5-triazine-2,4,6-trione.Depending on the reaction temperature, benzylidenebisurea forma either perhydro-2-phenyl-1,3,5-triazi
- Bakibaev, A. A.
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p. 1773 - 1775
(2007/10/03)
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