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61.
Sodium azide has been found to catalyse Knoevenagel condensation between aromatic aldehyde and cyano compound with active methylene hydrogens and this has led to a successful route for the one pot synthesis of 4,5-disubstituted 1,2,3-(NH)-triazoles from aldehydes through Knoevenagel-[3+2]cycloaddition-elimination sequence. In the formation of 5-aryl-2H-1,2,3-triazole-4-carbonitrile derivatives, the reaction has been found to occur efficiently in water. 相似文献
62.
Karthik Vikram Siva Shanmugam J. Scott Parent Ralph A. Whitney 《European Polymer Journal》2012,48(4):841-849
Solid-state rheometry and model compound reactions are used to investigate free radical reactions of N-arylmaleimide coagents with saturated and unsaturated polymers. N,N′-m-phenylene dimaleimide (BMI) is shown to provide superior cross-link densities over diacrylate and diallyl coagents for all of the polymers studied, including linear low density polyethylene (LLDPE), poly(ethylene oxide) (PEO), cis-poly(butadiene) (PBD) and cis-poly(isoprene) (PIP). Studies of the N-phenylmaleimide (NPM) + cis-cyclooctane system show that C–H bond addition to yield N-aryl-2-alkylsuccimide grafts is the predominant reaction pathway, as opposed to maleimide homopolymerization. In contrast, peroxide-initiated reactions of cis-cyclooctene with small NPM concentrations generate highly alternating poly(cycloctene-alt-N-phenylmaleimide) in high yield, indicating that unsaturated mers in materials such as PBD engage maleimides in an efficient alternating copolymerization between electron-rich and electron-deficient monomer pairs. Factors that affect the reactivity of different polymers in these C–H bond additions and alternating copolymerizations are discussed. 相似文献
63.
64.
Max O. D. G. Baker Nirukshan Shanmugam Chi L. L. Pham Sarah R. Ball Emma Sierecki Yann Gambin Megan Steain Margaret Sunde 《Molecules (Basel, Switzerland)》2022,27(11)
TIR-domain-containing adapter-inducing interferon-β (TRIF) is an innate immune protein that serves as an adaptor for multiple cellular signalling outcomes in the context of infection. TRIF is activated via ligation of Toll-like receptors 3 and 4. One outcome of TRIF-directed signalling is the activation of the programmed cell death pathway necroptosis, which is governed by interactions between proteins that contain a RIP Homotypic Interaction Motif (RHIM). TRIF contains a RHIM sequence and can interact with receptor interacting protein kinases 1 (RIPK1) and 3 (RIPK3) to initiate necroptosis. Here, we demonstrate that the RHIM of TRIF is amyloidogenic and supports the formation of homomeric TRIF-containing fibrils. We show that the core tetrad sequence within the RHIM governs the supramolecular organisation of TRIF amyloid assemblies, although the stable amyloid core of TRIF amyloid fibrils comprises a much larger region than the conserved RHIM only. We provide evidence that RHIMs of TRIF, RIPK1 and RIPK3 interact directly to form heteromeric structures and that these TRIF-containing hetero-assemblies display altered and emergent properties that likely underlie necroptosis signalling in response to Toll-like receptor activation. 相似文献
65.
Ponnusamy Shanmugam Vadivel Vaithiyanathan Baby Viswambharan Suchithra Madhavan 《Tetrahedron letters》2007,48(52):9190-9194
The reaction of the Baylis–Hillman adduct 2 of ferrocenealdehyde with various oxygen and carbon nucleophiles in the presence of montmorillonite K10 clay catalyst furnished highly functionalised trisubstituted alkene derivatives of ferrocenealdehyde in excellent yield. Synthetic use of one of products 7 has been demonstrated with the synthesis of a 1,3-diyne ether derivative of ferrocene 16 via an Eglinton coupling reaction. 相似文献
66.
cndo/Force method is used to evaluate redundancy-free internal valence force field (rfivff) for inplane vibrations of ethylene. The bending force constants, the stretch-band and bend-bend interaction force constants
are predicted reasonably well in magnitude and sign by this method; whereas stretching force constants and stretch-stretch
interactions are overestimated. Initial force field is set up by transferring stretching force constants from structurally-related
molecules and including the rest of the force constants fromcndo force field. The field so constructed is subjected to refinement by the least square method. A total of 64 vibrational frequencies
of C2H4, C2D4, C2H2D2 and their13C isotopic modifications are used to determine force field containing 15 parameters. The final force field is found to be
reasonable on the basis of frequency fits, potential energy distribution and band assignments. 相似文献
67.
Chockalingam Venkatachalapathy Muniappan Thirumalaikumar Shanmugam Muthusubramanian Kasi Pitchumani Shunmugaperumal Sivasubramanian 《合成通讯》2013,43(23):4041-4047
Abstract: The first clean and the facile clay catalysed synthesis of á,N-diarylnitrones in good yield is reported. 相似文献
68.
Kumar Sundaravel Vivek Rani Gandhi Uma Divyalakshmi Manohar Bhuvanesh Nattamai Muthusubramanian Shanmugam Perumal Subbu 《Molecular diversity》2019,23(3):669-680
Molecular Diversity - Expedient synthesis of benzosuberone-tethered spirooxindoles was accomplished by a three-component 1,3-dipolar cycloaddition reaction between azomethine ylide (generated in... 相似文献
69.
70.
Ponnusamy Shanmugam 《合成通讯》2013,43(24):4409-4415
The Montmorillonite K10 clay catalysed Friedel-Crafts aralkylation of compound 2 with a number of aromatic hydrocarbons furnished functionalised linear Aryl-Alkyl-Aryl systems in good yield. A comparative study of this reaction was carried out with mont-K10 and Fe3+-Mont-K10. 相似文献