- Binding interactions and FRET between bovine serum albumin and various phenothiazine-/anthracene-based dyes: A structure-property relationship
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The present study demonstrates binding interactions and F?rster resonance energy transfer (FRET) between bovine serum albumin (BSA) and a series of structurally and electronically diverse phenothiazine (PTZ) and anthracene (ANT) dyes. Upon selective excitation of tryptophan (Trp) residues of BSA, radiationless energy transfer to a dye takes place, resulting in fluorescence quenching of the former. Fluorescence quenching mechanisms, FRET parameters, possible locations, and binding constants of dyes with the BSA have been examined to deduce a structure-property relationship. The mechanism of quenching is apparently static in nature. PTZ dyes with heteroatoms and a pentyl tail (C5-PTZ) attached to them were found to have a stronger binding affinity with BSA as compared to ANT dyes. Stronger binding affinities of C5-PTZ dyes with BSA result in greater energy transfer efficiencies (ET). A dye with a strong electron-withdrawing group present in it has shown better energy accepting capability. A FRET study with dicyanoaniline (DCA) analogs of PTZ and ANT dyes (C5-PTZDCA and ANTDCA, respectively) revealed that ET depends on electronic and structural factors of molecules. An almost orthogonal geometry between ANT and DCA moieties (~79°) in ANTDCA induces the greater extent of electron transfer from ANT to DCA, showing a higher ET for this dye as compared to C5-PTZDCA in which the torsion angle is only ~38°. Further, the observed facts have been validated by experimentally determined bandgaps (using cyclic voltammetry experiments) for all the dyes. Thus, the hydrophobic character and the presence of interactive substituents along with the electron-accepting abilities majorly control the FRET for such dyes with BSA.
- Bhuin, Shouvik,Halder, Sayantan,Saha, Subit Kumar,Chakravarty, Manab
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Read Online
- Single-crystalline, size, and orientation controllable nanowires and ultralong microwires of organic semiconductor with strong photoswitching property
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Single-crystalline, precise size-controlled nanowires and ultralong microwires with lengths reaching several millimeters of organic semiconductor 1 were prepared in large scale by cast assembly. The size and density of the nanowires and microwires could be controlled by simply adjusting the concentration of 1 in casting solutions. More importantly, the formation of these nanowires and microwires showed no substrate and solvent dependence and was orientation controllable. Highly reproducible and sensitive photo response characteristics were observed in these nanowires and microwires. Fast and reversible photo-switchers based on multiple or individual single-crystal microwires were fabricated via "multi times gold wire mask moving" technique with switch ratio over 100.
- Jiang, Lang,Fu, Yanyan,Li, Hongxiang,Hu, Wenping
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Read Online
- Nanochannel-based {BaZn}-organic framework for catalytic activity on the cycloaddition reaction of epoxides with CO2and deacetalization-Knoevenagel condensation
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Herein, the rare combination of BaII (5s) and ZnII (3d) in the presence of the structure-oriented TDP6- ligand generated the nanochannel-based hybrid material {[(CH3)2NH2]2[BaZn(TDP)(H2O)]·DMF·5H2O}n (NUC-51, H6TDP = 2,4,6-tri(2,4-dicarboxyphenyl)pyridine), which possesses excellent physicochemical characteristics such as nanoscopic channels, high porosity, large specific surface area, and high heat/water-resistance. To the best of our knowledge, this is the first 3D [BaIIZnII(CO2)6(H2O)]-based nano-porous host framework, whose activated state possesses the coexistence of Lewis acid-base sites including 4-coordinated Zn2+ ions, 7-coordinated Ba2+ ions, uncoordinated carboxyl oxygen atoms, and Npyridine atoms. Catalytic experiments exhibited that activated NUC-51a possesses a high catalytic activity on the cycloaddition reactions of epoxides with CO2 at 55 °C, which can be ascribed to its structural advantages of nanoscale channels and rich bifunctional active sites. Moreover, NUC-51a could significantly accelerate the deacetalization-Knoevenagel condensation reaction in DMSO solvent at 70 °C.
- Chen, Hongtai,Fan, Liming,Gao, Yanpeng,Lv, Hongxiao,Zhang, Xiutang
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p. 3546 - 3556
(2022/03/14)
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- Two new calix[4]resorcinarene-based coordination cages adjusted by metal ions for the Knoevenagel condensation reaction
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Two new calix[4]resorcinarene-based coordination cages, namely, [Zn4(TPC4R)(PDC)4]·2DMF·6H2O (1-Zn) and [In11(TPC4R)2(PDC)16(μ2-OH)2(H2O)2]·[(CH
- Lu, Bing-Bing,Ma, Jian-Fang,Pei, Wen-Yuan,Wang, Tianqi,Yang, Jin
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supporting information
p. 9942 - 9948
(2021/07/28)
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- Photoelectrochemical and thermal characterization of aromatic hydrocarbons substituted with a dicyanovinyl unit
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Seven aromatic hydrocarbons bearing a dicyanovinyl unit were prepared to determine the relationship between both the number of aromatic rings and location of acceptor substituent on their thermal and optoelectronic properties. Additionally, the density functional theory calculations were performed. The obtained compounds showed temperatures of the beginning of thermal decomposition in the range of 137–289 °C, being above their respective melting points found between 88 and 248 °C. They were electrochemically active and showed quasi-reversible reduction process (except for 2-(phen-1-yl)methylene)malononitrile). Electrochemically estimated energy band gaps were below 3.0 eV, in the range of 2.10–2.50 eV. The absorption and emission spectra were recorded in CHCl3 and NMP and in solid state. All compounds strongly absorbed radiation with absorption maximum ranging from 307 to 454 nm ascribed to the intramolecular charge transfer between the donor and acceptor units. The aromatic hydrocarbons were luminescent in all investigated media and exhibited higher photoluminescence quantum yields in the solid state due to the aggregation induced emission phenomena. Electroluminescence ability of selected compounds was tested in a diode with guest-host configuration. Additionally, the selected compound together with a commercial N719 was applied in the dye-sensitized solar cell.
- Fabiańczyk, Aleksandra,Gnida, Pawe?,Kotowicz, Sonia,Kula, S?awomir,Ma?kowski, Sebastian,Ma?ecki, Jan Grzegorz,S?k, Danuta,Schab-Balcerzak, Ewa,Siwy, Mariola
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- Bifunctional design of stable metal-organic framework bearing triazole–carboxylate mixed ligand: Highly efficient heterogeneous catalyst for knoevenagel condensation reaction under mild conditions
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A highly water stable zinc metal–organic framework (ZnMOF), {[Zn(HL)2]}n, was synthesized using a triazole–carboxylate-based mixed ligand (L = 5-(4H-1,2,4-triazol-4-yl)isophthalic acid). A 2D MOF was formed by hydrothermal synthesis, and extended to a 3D supramolecular network through strong hydrogen bonding. This MOF was fully characterized by Fourier-transformation infrared spectroscopy, thermogravimetric analysis, single-crystal X-ray diffraction (XRD), powder XRD and elemental analysis. Owing to the d10 configuration of this ZnMOF, its luminescent properties were suitable for the sensing of the CN? ions over other anions, as inferred from the florescence result. However, regarding the catalytic mechanism, this ZnMOF showed a strong ability to react with CN?, which might be due to the hydrogen bonding between the COOH groups without coordination. This interaction behavior with CN? ions makes the ZnMOF a promising heterogeneous catalyst for Knoevenagel condensations using malononitrile and aldehyde derivatives as reactants under mild conditions. All reactions were conducted in water as a green solvent.
- Kumar, Sandeep,Li, Shuangshuang,Liu, Feixiong,Ren, Peng,You, Hengzhi,Zhao, Limin
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- Effecting structural diversity in a series of Co(ii)-organic frameworks by the interplay between rigidity of a dicarboxylate and flexibility of bis(tridentate) spanning ligands
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In a one-pot self-assembly reaction of Co(OAc)2·4H2O, thiophene-2,5-dicarboxylic acid (H2tdc) and four different bis(tridentate) polypyridyl spanning ligands under ambient conditions, a series of structurally diverse metal-organic frameworks has been synt
- Gogia, Alisha,Khullar, Sadhika,Laha, Biswajit,Mandal, Sanjay K.
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p. 12298 - 12310
(2020/10/02)
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- Design, synthesis and biological evaluation of new series of hexahydroquinoline and fused quinoline derivatives as potent inhibitors of wild-type EGFR and mutant EGFR (L858R and T790M)
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New series of hexahydroquinoline and fused quinoline derivatives were designed and synthesized. The thirty seven new compounds were screened for in vitro antitumor activity against HepG2, HCT-116 and MCF-7 cancer cells. Results indicated that compounds 2e
- Shaheen, Mennatallah A.,El-Emam, Ali A.,El-Gohary, Nadia S.
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- 1,4,5,6,7,8-Hexahydroquinolines and 5,6,7,8-tetrahydronaphthalenes: A new class of antitumor agents targeting the colchicine binding site of tubulin
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New series of 2-amino-1,4,5,6,7,8-hexahydroquinoline-3-carbonitriles 3a,b and 2-amino-5,6,7,8-tetrahydronaphthalene-1,3-dicarbonitriles 4a-h were synthesized and evaluated for their antitumor activity. In vitro antitumor screening of the new members again
- Shaheen, Mennatallah A.,El-Emam, Ali A.,El-Gohary, Nadia S.
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supporting information
(2021/06/14)
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- Two Hg(II)-based Macrocycles Offering Hydrogen Bonding Cavities: Influence of Cavity Structure on Heterogeneous Catalysis
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We present synthesis and characterization of two Hg-macrocycles offering H-bonding based cavities of varying dimensions. Both Hg-macrocycles illustrate noteworthy difference in their catalytic performance that has been related to their cavity structures.
- Pachisia, Sanya,Gupta, Rajeev
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p. 6039 - 6047
(2019/10/21)
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- Method used for preparing substituted 1, 3-malononitrile
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The invention belongs to the field of fine chemical product preparation and medicine intermediate synthesis, and relates to a method used for preparing substituted 1, 3-malononitrile. According to themethod, an aldehyde or a ketone and malononitrile are subjected to condensation reaction to prepare substituted 1, 3-malononitrile, wherein water is taken as a solvent, the aldehyde or the ketone andmalononitrile are subjected to Knoevenagel condensation under catalytic effect of zinc proline so as to obtain the corresponding substituted 1, 3-malononitrile. The method conditions are mild; operation is convenient; water is taken as a reaction solvent, so that the method is friendly to the environment; and the application prospect is promising.
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Paragraph 0034-0035
(2019/08/07)
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- Hypervalent Iodine(III)-Catalyzed Epoxidation of β-Cyanostyrenes
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A convenient approach for the synthesis of β-cyanoepoxides is illustrated by iodine(III)-catalyzed epoxidation of electron-deficient β-cyanostyrenes, wherein the active catalytic iodine(III) species was generated in situ. The epoxidation of β-cyanostyrenes was performed using 10 molpercent PhI as precatalyst in the presence of 2.0 equivalents Oxone as an oxidant and 2.4 equivalents of TFA as an additive at room temperature under ultrasonic radiations. The β-cyanoepoxides were isolated in good to excellent yields in a short reaction time.
- Mangaonkar, Saeesh R.,Singh, Fateh V.
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p. 4473 - 4486
(2019/11/21)
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- Impact of an aryl bulky group on a one-pot reaction of aldehyde with malononitrile and: N-substituted 2-cyanoacetamide
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In this study, we successfully explored the effect of steric hindrance on the one-pot reaction of different aryl aldehydes with malononitrile and N-substituted 2-cyanoacetamide in the presence of piperidinium acetate as the catalyst. It involved the Knoevenagel condensation of the aldehyde and malononitrile to produce arylidene malononitrile as an intermediate, which was further treated with N-substituted 2-cyanoacetamide to give 6-Amino-2-pyridone-3,5-dicarbonitrile derivatives when the less steric bulky group was involved. High steric hindrance changed the earlier reaction route and gave N-substituted 2-cyanoacrylamides via a slower route.
- Vala, Ruturajsinh M.,Patel, Divyang M.,Sharma, Mayank G.,Patel, Hitendra M.
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p. 28886 - 28893
(2019/09/30)
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- Switching acidic and basic catalysis through supramolecular functionalization in a porous 3D covalent imine-based material
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Non-covalent inclusion of small acid and base molecules (CH3COOH and NEt3) in an imine structure based on micrometre COF-300 crystals and amorphous nanoparticles results in the facile modulation of their acid-base properties. Such a
- Luis-Barrerra, Javier,Cano, Rafael,Imani-Shakibaei, Ghazaleh,Heras-Domingo, Javier,Pérez-Carvajal, Javier,Imaz, Inhar,Maspoch, Daniel,Solans-Monfort, Xavier,Alemán, José,Mas-Ballesté, Rubén
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p. 6007 - 6014
(2019/11/14)
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- Hierarchical Micro- and Mesoporous Zn-Based Metal–Organic Frameworks Templated by Hydrogels: Their Use for Enzyme Immobilization and Catalysis of Knoevenagel Reaction
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Encapsulation of enzymes in metal–organic frameworks (MOFs) is often obstructed by the small size of the orifices typical of most reported MOFs, which prevent the passage of larger-size enzymes. Here, the preparation of hierarchical micro- and mesoporous
- Cheng, Kaipeng,Svec, Frantisek,Lv, Yongqin,Tan, Tianwei
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- Function-Structure Relationship in Metal-Organic Frameworks for Mild, Green, and Fast Catalytic C-C Bond Formation
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Tunability in chemical functionality is a promising characteristic of metal-organic frameworks (MOFs), which plays an important role in developing and improving the practical applications of MOFs. Here, we applied this important feature of MOFs to be in line with sustainable development and green chemistry principles through the synthesis of MOF-based heterogeneous organocatalysts. According to our green functionalization strategy, some isostructural MOFs (azine decorated TMU-4 with the formula [Zn(OBA)(BPDB)0.5]n·2DMF, azine-methyl functionalized TMU-5 with the formula [Zn(OBA)(BPDH)0.5]n·1.5DMF, dihydro-tetrazine decorated TMU-34 with the formula [Zn(OBA)(H2DPT)0.5]n·DMF, and tetrazine functionalized TMU-34(-2H) with the formula [Zn(OBA)(DPT)0.5]n·DMF, where H2OBA = 4,4′-oxybis(benzoic acid), BPDB = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene, BPDH = 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene, H2DPT = 3,6-di(pyridin-4-yl)-1,4-dihydro-1,2,4,5-tetrazine, and DPT = 3,6-di(pyridin-4-yl)-1,2,4,5-tetrazine) have been applied for mild, green, and fast Knoevenagel condensation. These frameworks display different Lewis basic catalytic activities owing to their different functionality and function accessibility. Contrary to extensive articles published about Knoevenagel condensation, this study involves the rare examples in Knoevenagel condensation with such mild conditions (room temperature and atmospheric pressure) and with a green solution (water as the solvent). Due to the combined synergic effects of the Lewis basicity of TMU-frameworks, the amphoteric and hydrogen bond-participating nature of water molecules, maximum conversion times are reached just after 30 min (for TMU-5) and 60 min (for TMU-34). Stability and recyclability tests show that TMU-5 and TMU-34 are completely stable in water at reaction conditions and can retain their crystallinity, porosity, and functionality even after five cycles without any specific reduction in their catalytic conversion. Since, in many cases, amine decorated MOFs are applied in Knoevenagel catalyzed condensation, this study is beneficial in providing information about the effects of azine and tetrazine functional groups in reactant activation and the acceleration of Knoevenagel condensation.
- Razavi, Sayed Ali Akbar,Morsali, Ali
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p. 14429 - 14439
(2019/11/03)
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- Ultrasound-assisted rapid synthesis of β-cyanoepoxides using hypervalent iodine reagents
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An elegant approach for the rapid synthesis of β-cyanoepoxides 3 by the epoxidation of β-cyanostyrenes 1 with PIDA 2a is described. The epoxidation of β-cyanostyrenes 1 was performed with 1.2 equiv. of PIDA 2a in MeCN-H2O (1:1) at room temperature in ultrasonic bath. The epoxidation reactions were completed in short reaction time and β-cyanoepoxides 3 were isolated in 69–94% yields.
- Singh, Fateh V.,Mangaonkar, Saeesh R.,Kole, Priyanka B.
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supporting information
p. 2169 - 2176
(2018/07/21)
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- Synthesis of Metallomacrocycle and Coordination Polymers with Pyridine-Based Amidocarboxylate Ligands and Their Catalytic Activities towards the Henry and Knoevenagel Reactions
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The reactions of 3,3′-{(pyridine-2,6-dicarbonyl)bis(azanediyl)}dibenzoic acid (H2L) with zinc(II), cadmium(II), and samarium(III) nitrates were studied, and the obtained compounds, [Zn(1κO:2κO′-L)(H2O)2]n (1), [
- Karmakar, Anirban,Rúbio, Guilherme M. D. M.,Guedes da Silva, M. Fátima C.,Pombeiro, Armando J. L.
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p. 865 - 877
(2018/12/10)
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- Defect engineering of highly stable lanthanide metal-organic frameworks by particle modulation for coating catalysis
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By virtue of their structural periodicity, tunability, high porosity and rich functionality, metal-organic frameworks (MOFs) are of great interest in catalysis. However, MOF crystals are fragile and difficult to use as robust adsorbents or catalysts witho
- Chen, Yifa,Zhang, Shenghan,Chen, Fan,Cao, Sijia,Cai, Ya,Li, Siqing,Ma, Hongwei,Ma, Xiaojie,Li, Pengfei,Huang, Xianqiang,Wang, Bo
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supporting information
p. 342 - 348
(2018/01/12)
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- A metalloligand appended with benzimidazole rings: Tetranuclear [CoZn3] and [CoCd3] complexes and their catalytic applications
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A novel Co3+-based metalloligand 1 offering appended benzimidazole rings has been prepared and utilized for the synthesis of tetranuclear [CoZn3] (2 and 2-Cl) and [CoCd3] (3) heterometallic coordination complexes (HCCs). C
- Pandey, Saurabh,Bansal, Deepak,Gupta, Rajeev
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p. 9847 - 9856
(2018/06/18)
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- A Dynamic Three-Dimensional Covalent Organic Framework
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A guest-induced reversible crystal-structure transformation is identified in a new 3D covalent organic framework (COF) by comprehensive analyses using powder X-ray diffraction, organic vapor sorption isotherm, and 129Xe NMR spectroscopy. The revolving imine bond in interpenetrating 3D networks is uncovered as the key to the dynamic behavior, the potential applications of which are illustrated by gas separation and heterogeneous catalysis, thus paving the way to the design of stimuli-responsive and multifunctional COF materials.
- Ma, Yun-Xiang,Li, Zhi-Jun,Wei, Lei,Ding, San-Yuan,Zhang, Yue-Biao,Wang, Wei
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supporting information
p. 4995 - 4998
(2017/05/04)
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- Molecular modeling of drug-pathophysiological Mtb protein targets: Synthesis of some 2-thioxo-1, 3-thiazolidin-4-one derivatives as anti-tubercular agents
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Twenty novel 2-thioxo-1, 3-thiazolidin-4-one derivatives (5a-5t) were synthesized and evaluated for their antitubercular activity. The structure of the compounds was confirmed by IR, NMR and Mass Spectroscopy methods. In addition, single-crystal X-ray diffraction was performed for compound 5a. All the synthesized compounds were screened for their in-vitro antimycobacterial activity against MTB (H37RV, ATCC No: 27294) by Alamar Blue assay method. Compounds 5r, 5k, 5t displayed most potent in-vitro activity with MICs of 0.05, 0.1, 0.2 μg/ml concentrations respectively which are comparatively potent than the standards. Molecular docking and dynamics simulations were performed to find out the plausible mechanism of the titled compounds.
- Noorulla,Suresh, Ayyadurai Jerad,Devaraji, Vinod,Mathew, Bijo,Umesh, Devi
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p. 682 - 696
(2017/07/13)
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- Two pillared metal-organic frameworks comprising a long pillar ligand used as fluorescent sensors for nitrobenzene and heterogeneous catalysts for the Knoevenagel condensation reaction
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Two new pillared zinc and cadmium-organic frameworks were synthesized by incorporating two different organic linkers, namely 2-aminoterephthalic acid as an oxygen-donor linker and N4,N4'-bis(pyridin-4-ylmethylene)-biphenyl-4,4'-diamine as a long pillaring strut. The structures of these two frameworks were analyzed using X-ray crystallography, FT-IR spectroscopy, thermogravimetric and elemental analyses. Their structural features as well as their stability were studied. These two MOFs having the same organic composition and the same network topology but different inorganic nodes differ in their chemical stability. Also, these two frameworks respond differently to nitrobenzene when they are used as fluorescent sensors. Furthermore, the catalytic behavior of one of these frameworks toward the Knoevenagel condensation reaction was investigated.
- Ghasempour, Hosein,Azhdari Tehrani, Alireza,Morsali, Ali,Wang, Jun,Junk, Peter C.
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p. 2463 - 2468
(2016/04/26)
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- Switching on Supramolecular Catalysis via Cavity Mediation and Electrostatic Regulation
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Synthetic supercontainers constructed from divalent metal ions, carboxylate linkers, and sulfonylcalix[4]arene-based container precursors exhibit great promise as enzyme mimics that function in organic solvents. The capacity of these artificial hosts to catalyze Knoevenagel condensation can be switched on when the aldehyde substrate possesses a molecular size and shape matching the nanocavity of the supercontainers. In contrast, little reactivity is observed for other aldehydes that do not match the binding pocket. This substrate-dependent catalytic selectivity is attributed to the Br?nsted acidity of the metal-bound water molecules located inside the nanocavity, which is amplified when the size/shape of the aldehyde substrate fits the binding cavity. The electrostatic environment of the binding cavity and the Br?nsted acidity of the supercontainer can be further modulated using tetraalkylammonium-based regulators, leading to higher reactivity for the otherwise unreactive aldehydes.
- Qiao, Yupu,Zhang, Long,Li, Jia,Lin, Wei,Wang, Zhenqiang
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supporting information
p. 12778 - 12782
(2016/10/04)
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- Peculiarities of 2-amino-3-R-4-aryl-4H-pyranes multicomponent synthesis derived from 1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide
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The new 2-amino-3-R-4-aryl-6-ethyl-4,6-dihydropyrano[3,2-c][2,1]benzothiazine 5,5-dioxides were synthesized via three-component interaction of 1H-2,1-benzothiazin-4(3H)-one 2,2-dioxide with arylcarbaldehydes and active methylene nitriles. Depending on the
- Lega, Dmitry A.,Gorobets, Nikolay Yu.,Chernykh, Valentine P.,Shishkina, Svetlana V.,Shemchuk, Leonid A.
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p. 16087 - 16099
(2016/02/26)
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- Contemporary development in sequential Knoevenagel, Michael addition multicomponent reaction for the synthesis of 4-Aryl-5-oxo-5H-indeno[1,2-b]pyridine-3-carbonitrile
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An uncatalyzed efficient synthesis of bioactive pyridine derivatives has been investigated for the first time by a three-component sequential multicomponent reaction tackled with aromatic aldehydes, malononitrile, and 1,3-indandione via Knoevenagel condensation followed by Michael addition. The difference between the domino multicomponent and sequential multicomponent reaction is emphasized by this methodology. The reaction proceeds at ambient temperature without frequently useful N-source like ammonium salt for the construction of N-heterocycles, which makes this protocol a novel synthetic route for the preparation of the indenopyridine skeleton.
- Patravale, Ajinkya A.,Gore, Anil H.,Patil, Dipti R.,Kolekar, Govind B.,Deshmukh, Madhukar B.,Choudhari, Prafulla B.,Bhatia, Manish S.,Anbhule, Prashant V.
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p. 2919 - 2935
(2016/04/05)
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- A carboxylate-rich metalloligand and its heterometallic coordination polymers: Syntheses, structures, topologies, and heterogeneous catalysis
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This work reports three heterometallic coordination polymers (HCPs), namely, [{(1′)2Zn8Na2(H2O)21}·20H2O]n (2), [{(1′)(1')Cd8(H2O)21}·32H2/
- Srivastava, Sumit,Kumar, Vijay,Gupta, Rajeev
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p. 2874 - 2886
(2016/06/01)
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- A metalloligand appended with thiazole rings: Heterometallic {Co3+-Zn2+} and {Co3+-Cd2+} complexes and their heterogeneous catalytic applications
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This work describes a Co3+-based metalloligand containing appended thiazole rings and its reactions with secondary metal ions to produce heterometallic {Co3+-Zn2+} and {Co3+-Cd2+} complexes. Structural studies show that some of the appended thiazole rings from the metalloligand coordinate to secondary metal ions, whereas the remaining ones act as hydrogen-bond acceptors to metal-bound CH3OH or H2O molecules. These heterometallic complexes function as reusable heterogeneous catalysts for the ring-opening reactions of epoxides as well as cyanation and Knoevenagel condensation reactions of aldehydes. The catalytic results illustrate that the microenvironment remains intact during the catalysis and potentially enhances the substrate interaction with the Lewis acidic secondary metal ions.
- Bansal, Deepak,Hundal, Geeta,Gupta, Rajeev
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p. 1022 - 1032
(2015/06/24)
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- Heterometallic coordination polymers assembled from trigonal trinuclear Fe2Ni-pivalate blocks and polypyridine spacers: Topological diversity, sorption, and catalytic properties
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Linkage of the trigonal complex [Fe2NiO(Piv)6] (where Piv- = pivalate) by a series of polypyridine ligands, namely, tris(4-pyridyl)triazine (L2), 2,6-bis(3-pyridyl)-4-(4-pyridyl)pyridine (L3), N-(bis-2,2-(4-pyridyloxymethyl)-3-(4-pyridyloxy)propyl))pyridone-4 (L4), and 4-(N,N-diethylamino)phenyl-bis-2,6-(4-pyridyl)pyridine (L5) resulted in the formation of novel coordination polymers [Fe2NiO(Piv)6(L2)]n (2), [Fe2NiO(Piv)6(L3)]n (3), [Fe2NiO(Piv)6(L4)]n·nHPiv (4), and [{Fe2NiO(Piv)6}4{L5}6]n·3nDEF (5, where DEF is N,N-diethylformamide), which were crystallographically characterized. The topological analysis of 3, 4, and 5 disclosed the 3,3,4,4-connected 2D (3, 4) or 3,4,4-connected 1D (5) underlying networks which, upon further simplification, gave rise to the uninodal 3-connected nets with the respective fes (3, 4) or SP 1-periodic net (4,4)(0,2) (5) topologies, driven by the cluster [Fe2Ni(?14;3-O)(?14;-Piv)6] nodes and the polypyridine ?14;3-L3,4 or ?14;2-L5 blocks. The obtained topologies were compared with those identified in other closely related derivatives [Fe2NiO(Piv)6(L1)]n (1) and {Fe2NiO(Piv)6}8{L6}12 (6), where L1 and L6 are tris(4-pyridyl)pyridine and 4-(N,N-dimethylamino)phenyl-bis-2,6-(4-pyridyl)pyridine, respectively. It was shown that a key structure-driven role in defining the dimensionality and topology of the resulting coordination network is played by the type of polypyridine spacer. Compounds 2 and 3 possess a porous structure, as confirmed by the N2 and H2 sorption data at 78 K. Methanol and ethanol sorption by 2 was also studied indicating that the pores filled by these substrates did not induce any structural rearrangement of this sorbent. Additionally, porous coordination polymer 2 was also applied as a heterogeneous catalyst for the condensation of salicylaldehyde or 9-anthracenecarbaldehyde with malononitrile. The best activity of 2 was observed in the case of salicylaldehyde substrate, resulting in up to 88% conversion into 2-imino-2H-chromen-3-carbonitrile.
- Sotnik, Svetlana A.,Polunin, Ruslan A.,Kiskin, Mikhail A.,Kirillov, Alexander M.,Dorofeeva, Victoria N.,Gavrilenko, Konstantin S.,Eremenko, Igor L.,Novotortsev, Vladimir M.,Kolotilov, Sergey V.
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supporting information
p. 5169 - 5181
(2015/06/16)
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- A general post-synthetic modification approach of amino-tagged metal-organic frameworks to access efficient catalysts for the Knoevenagel condensation reaction
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In this manuscript, four common transition-metal derived metal-organic frameworks have been extensively investigated as heterogeneous catalyst supports for Knoevenagel condensation reactions. A simple post-synthetic modification strategy was employed for the rapid and facile introduction of a primary alkyl amino group. The resulting novel MOF-RNH2 catalysts showed greatly enhanced Knoevenagel condensation reactivities towards a variety of aldehyde electrophiles. IRMOF-3 proved to be an unsuitable heterogeneous catalyst support due to its fragile nature upon treatment with bases. The novel zirconium based UiO-66-NH-RNH2 and chromium based Cr-MIL-101-NH-RNH2 materials showed excellent catalytic reactivities, while being highly convenient to synthesize. The basic catalytic activity was further extended to the Henry reaction, and excellent catalytic reactivity was achieved. The size-selectivity was also studied to show that the Knoevenagel condensation occurred inside of the porous structure of the MOF catalyst. The recycling properties of zirconium, aluminum and chromium derived MOFs were evaluated and zirconium based UiO-66 and chromium based Cr-MIL-101 showed excellent catalytic efficiency after five reaction cycles.
- Luan, Yi,Qi, Yue,Gao, Hongyi,Andriamitantsoa, Radoelizo S.,Zheng, Nannan,Wang, Ge
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supporting information
p. 17320 - 17331
(2015/08/24)
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- Amine-grafted on lanthanide metal-organic frameworks: Three solid base catalysts for Knoevenagel condensation reaction
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A post-synthetic modification strategy has been used to prepare three solid base catalysts, including Er(btc)(ED)0.75(H2O)0.25 (2, btc = 1,3,5-benzenetricarboxylates, ED = 1,2-ethanediamine), Er(btc)(PP)0.55(Hs
- Ren, Yanwei,Lu, Jiaxian,Jiang, Ou,Cheng, Xiaofei,Chen, Jun
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p. 1949 - 1955
(2015/11/17)
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- Heterometallic coordination polymers: syntheses, structures and heterogeneous catalytic applications
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A metalloligand Na[Co(L1)2] (1) of the ligand H2L1 (N2,N6-bis(4,5-dihydrothiazol-2-yl)pyridine-2,6-dicarboxamide) offering appended thiazoline rings has been used for the synthesis of one-dimensional {Co3+-Zn2+} (2), {Co3+-Cd2+} (3) and {Co3+-Hg2+} (4) coordination polymers. 1 offers appended thiazoline rings having both soft sulphur and hard nitrogen donors. The crystal structures of 2 and 3 display the coordination of hard thiazoline-N donors to Zn2+ and Cd2+ ions. Interestingly, 4 illustrates the bonding through both hard thiazoline-N and soft thiazoline-S donors. The three heterometallic coordination polymers have been used as reusable heterogeneous catalysts for the ring-opening reactions of oxiranes and thiiranes; Knoevenagel condensation of benzaldehydes and benzothialdehydes; and cyanation reactions of aldehydes and carbothialdehydes. Our results demonstrate that the relative size and Lewis acidity of secondary metals potentially control the catalytic outcome via preferential interaction with the substrates.
- Bansal, Deepak,Pandey, Saurabh,Hundal, Geeta,Gupta, Rajeev
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p. 9772 - 9781
(2015/12/01)
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- Amino-functionalized Zr(IV) metal-organic framework as bifunctional acid-base catalyst for Knoevenagel condensation
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The amino-functionalized metal-organic framework of Zr(IV) with 2-aminoterephthalate, UiO-66-NH2, was studied as a solid catalyst for Knoevenagel condensation. The material can efficiently catalyze the condensation reaction of benzaldehyde with
- Yang, Yang,Yao, Hong-Fei,Xi, Fu-Gui,Gao, En-Qing
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p. 198 - 205
(2014/06/24)
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- Solvent-free, one-pot synthesis of pentasubstituted cyclopropanes in the presence of BrCN and EtONa by milling
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A solvent-free, one-pot process for the preparation of pentasubstituted 3-arylcyclopropane-1,1,2,2-tetracarbonitriles in the presence of solid sodium ethoxide by milling was achieved. The one-pot reaction of aromatic aldehydes and dialdehydes with malonon
- Noroozi Pesyan, Nader,Rezaee, Mohammad
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p. 1165 - 1171
(2014/06/24)
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- A new, fast and easy strategy for one-pot synthesis of full substituted cyclopropanes: Direct transformation of aldehydes to 3-aryl-1,1,2,2- tetracyanocyclopropanes
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A new, fast and easy method for one-pot reaction of aromatic aldehydes and dialdehydes with malononitrile and cyanogen bromide has been developed to afford full substituted 3-arylcyclopropane-1,1,2,2-tetracarbonitriles in excellent yields in very short time (about 5 seconds). The structures elucidations were characterized by IR, 1H NMR, 13C NMR, mass spectrometry and X-ray crystallography techniques. For these compounds the crystallographic data showed two structures in mirror image in solid case and one distinct structure in solution. The reaction mechanism was discussed.
- Noroozi Pesyan, Nader,Kimia, Mohammad Ali,Jalilzadeh, Mohammad,Sahin, Ertan
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- Steric hindrance-enforced distortion as a general strategy for the design of fluorescence "turn-on" cyanide probes
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For the rational design of fluorescence "turn-on" cyanide probes, a general strategy is developed by introducing a dicyanovinyl group at the sterically demanding position of a large π framework. The Royal Society of Chemistry 2013.
- Chen, Bin,Ding, Yubin,Li, Xin,Zhu, Weihong,Hill, Jonathan P.,Ariga, Katsuhiko,Xie, Yongshu
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supporting information
p. 10136 - 10138
(2013/10/22)
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- Synthesis, characterisation and bioactivity of polysubstituted 1-(4-(1H-pyrrol-1-yl)phenyl)-1H-pyrrole derivatives
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1,4-Phenylenediamine reacted readily with chloroacetone to give 1,4-bis[(2-oxopropyl)amino]benzene which was used to prepare 1-(4-(1H-pyrrol-1-yl)phenyl)-1H-pyrrole derivatives in a one pot reaction with dimethylformamide dimethylacetal or triethyl orthof
- Elassar, Abdel-Zaher A.
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experimental part
p. 328 - 332
(2012/10/08)
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- Synthesis of 2-amino-4-aryl-3-cyano-6-methyl-5-ethoxycarbonyl-4H-pyrans
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A one-step electrochemical synthesis of the title compounds has been devised. The starting materials are aromatic and heteroaromatic aldehydes, malononitrile and ethyl acetoacetate. The overall reaction is catalyzed by electrogenerated base (EGB) formed a
- Shestopalov, Anatoliy M.,Niazimbetova, Zukhra I.,Evans, Dennis H.,Niyazymbetov, Murat E.
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p. 1101 - 1107
(2007/10/03)
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- Intramolecular Charge Transfer Properties of Dicyanovinyl-Substituted Aromatics
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A series of five dicyanovinyl (DCV)-substituted aromatic compounds (referred to collectively as Ar-DCV, where Ar = 1-phenyl, 1-naphthyl, 9-anthracenyl, 9-phenanthrenyl, and 1-pyrenyl) were prepared and their ground- and excited-state properties were examined.Solvent-dependent NMR studies indicate that the ground state of the Ar-DCV compounds is polar.Strong intramolecular charge transfer (ICT) absorption bands were observed for each compound.The position of the ICT absorption is nearly independent of solvent polarity and the molar absorptivity is related to the twist angle between the aromatic donor and the DCV acceptor.The fluorescence spectra are highly solvatochromatic and the fluorescence energy correlates with the solvent polarity parameter Δf in a variety of solvents.The fluorescence quantum yields are low and no emission was observed from phenyl-DCV.An excited state model is proposed which explains the solvent dependence of the ICT absorption and emission of the series of Ar-DCV compounds.
- Katritzky, Alan R.,Zhu, Dong-Wei,Schanze, Kirk S.
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p. 5737 - 5742
(2007/10/02)
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