Relevant bibliographies by topics / Covalent approaches

Academic literature on the topic 'Covalent approaches'

Author: Grafiati
Published: 10 December 2022
Last updated: 28 January 2023

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Journal articles on the topic "Covalent approaches"

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Tang, Bohan, Jiantao Zhao, Jiang-Fei Xu, and Xi Zhang. "Tuning the stability of organic radicals: from covalent approaches to non-covalent approaches." Chemical Science 11, no. 5 (2020): 1192–204. http://dx.doi.org/10.1039/c9sc06143f.

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van Maarseveen, Jan H., Milo D. Cornelissen, and Simone Pilon. "Covalently Templated Syntheses of Mechanically Interlocked Molecules." Synthesis 53, no. 24 (October 8, 2021): 4527–48. http://dx.doi.org/10.1055/a-1665-4650.

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AbstractMechanically interlocked molecules (MiMs), such as catenanes and rotaxanes, exhibit unique properties due to the mechanical bond which unites their components. The translational and rotational freedom present in these compounds may be harnessed to create stimuli-responsive MiMs, which find potential application as artificial molecular machines. Mechanically interlocked structures such as lasso peptides have also been found in nature, making MiMs promising albeit elusive targets for drug discovery. Although the first syntheses of MiMs were based on covalent strategies, approaches based on non-covalent interactions rose to prominence thereafter and have remained dominant. Non-covalent strategies are generally short and efficient, but do require particular structural motifs which are difficult to alter. In a covalent approach, MiMs can be more easily modified while the components may have increased rotational and translational freedom. Both approaches have complementary merits and combining the unmatched efficiency of non-covalent approaches with the scope of covalent syntheses may open up vast opportunities. In this review, recent covalently templated syntheses of MiMs are discussed to show their complementarity and anticipate future developments in this field.1 Introduction2 Tetrahedral Templates2.1 A Carbonate Template for Non-Rusty Catenanes2.2 All-Benzene Catenanes on a Silicon Template2.3 Backfolding from Quaternary Carbon3 Planar Templates3.1 Rotaxanes Constructed in a Ring3.2 Hydrindacene as a Dynamic Covalent Template3.3 Templating on Tri- and Tetrasubstituted Benzenes4 Conclusion
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Georgakilas, Vasilios, Michal Otyepka, Athanasios B. Bourlinos, Vimlesh Chandra, Namdong Kim, K. Christian Kemp, Pavel Hobza, Radek Zboril, and Kwang S. Kim. "Functionalization of Graphene: Covalent and Non-Covalent Approaches, Derivatives and Applications." Chemical Reviews 112, no. 11 (September 25, 2012): 6156–214. http://dx.doi.org/10.1021/cr3000412.

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Bjij, Imane, Pritika Ramharack, Shama Khan, Driss Cherqaoui, and Mahmoud E. S. Soliman. "Tracing Potential Covalent Inhibitors of an E3 Ubiquitin Ligase through Target-Focused Modelling." Molecules 24, no. 17 (August 28, 2019): 3125. http://dx.doi.org/10.3390/molecules24173125.

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The Nedd4-1 E3 Ubiquitin ligase has been implicated in multiple disease conditions due its overexpression. Although the enzyme may be targeted both covalently and non-covalently, minimal studies provide effective inhibitors against it. Recently, research has focused on covalent inhibitors based on their characteristic, highly-selective warheads and ability to prevent drug resistance. This prompted us to screen for new covalent inhibitors of Nedd4-1 using a combination of computational approaches. However, this task proved challenging due to the limited number of electrophilic moieties available in virtual libraries. Therefore, we opted to divide an existing covalent Nedd4-1 inhibitor into two parts: a non-covalent binding group and a pre-selected α, β-unsaturated ester that forms the covalent linkage with the protein. A non-covalent pharmacophore model was built based on molecular interactions at the binding site. The pharmacophore was then subjected to virtual screening to identify structurally similar hit compounds. Multiple filtrations were implemented prior to selecting four hits, which were validated with a covalent conjugation and later assessed by molecular dynamic simulations. The results showed that, of the four hit molecules, Zinc00937975 exhibited advantageous molecular groups, allowing for favourable interactions with one of the characteristic cysteine residues. Predictive pharmacokinetic analysis further justified the compound as a potential lead molecule, prompting its recommendation for confirmatory biological evaluation. Our inhouse, refined, pharmacophore model approach serves as a robust method that will encourage screening for novel covalent inhibitors in drug discovery.
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Sotriffer, Christoph. "Docking of Covalent Ligands: Challenges and Approaches." Molecular Informatics 37, no. 9-10 (June 21, 2018): 1800062. http://dx.doi.org/10.1002/minf.201800062.

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Kizior, Beata, Mariusz Michalczyk, Jarosław J. Panek, Wiktor Zierkiewicz, and Aneta Jezierska. "Unraveling the Nature of Hydrogen Bonds of “Proton Sponges” Based on Car-Parrinello and Metadynamics Approaches." International Journal of Molecular Sciences 24, no. 2 (January 12, 2023): 1542. http://dx.doi.org/10.3390/ijms24021542.

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The nature of intra- and intermolecular non-covalent interactions was studied in four naphthalene derivatives commonly referred to as “proton sponges”. Special attention was paid to an intramolecular hydrogen bond present in the protonated form of the compounds. The unsubstituted “proton sponge” served as a reference structure to study the substituent influence on the hydrogen bond (HB) properties. We selected three compounds substituted by methoxy, amino, and nitro groups. The presence of the substituents either retained the parent symmetry or rendered the compounds asymmetric. In order to reveal the non-covalent interaction properties, the Hirshfeld surface (HS) was computed for the crystal structures of the studied compounds. Next, quantum-chemical simulations were performed in vacuo and in the crystalline phase. Car–Parrinello molecular dynamics (CPMD), Path Integral Molecular Dynamics (PIMD), and metadynamics were employed to investigate the time-evolution changes of metric parameters and free energy profile in both phases. Additionally, for selected snapshots obtained from the CPMD trajectories, non-covalent interactions and electronic structure were studied. Quantum theory of atoms in molecules (QTAIM) and the Density Overlap Regions Indicator (DORI) were applied for this purpose. It was found based on Hirshfeld surfaces that, besides intramolecular hydrogen bonds, other non-covalent interactions are present and have a strong impact on the crystal structure organization. The CPMD results obtained in both phases showed frequent proton transfer phenomena. The proton was strongly delocalized in the applied time-scale and temperature, especially in the PIMD framework. The use of metadynamics allowed for tracing the free energy profiles and confirming that the hydrogen bonds present in “proton sponges” are Low-Barrier Hydrogen Bonds (LBHBs). The electronic and topological analysis quantitatively described the temperature dependence and time-evolution changes of the electronic structure. The covalency of the hydrogen bonds was estimated based on QTAIM analysis. It was found that strong hydrogen bonds show greater covalency, which is additionally determined by the proton position in the hydrogen bridge.
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Sainz-Urruela, Carlos, Soledad Vera-López, María Paz San Andrés, and Ana M. Díez-Pascual. "Surface functionalization of graphene oxide with tannic acid: Covalent vs non-covalent approaches." Journal of Molecular Liquids 357 (July 2022): 119104. http://dx.doi.org/10.1016/j.molliq.2022.119104.

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Sakamaki, Daisuke, Samrat Ghosh, and Shu Seki. "Dynamic covalent bonds: approaches from stable radical species." Materials Chemistry Frontiers 3, no. 11 (2019): 2270–82. http://dx.doi.org/10.1039/c9qm00488b.

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Gautam, Chandkiram, and Selvam Chelliah. "Methods of hexagonal boron nitride exfoliation and its functionalization: covalent and non-covalent approaches." RSC Advances 11, no. 50 (2021): 31284–327. http://dx.doi.org/10.1039/d1ra05727h.

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Nigel-Etinger, Izana, Atif Mahammed, and Zeev Gross. "Covalent versus non-covalent (biocatalytic) approaches for enantioselective sulfoxidation catalyzed by corrole metal complexes." Catalysis Science & Technology 1, no. 4 (2011): 578. http://dx.doi.org/10.1039/c1cy00046b.

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Dissertations / Theses on the topic "Covalent approaches"

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Comí, Bonachí Marc. "Biobased polyurethanes with tunable properties through covalent and non-covalent approaches." Doctoral thesis, Universitat Rovira i Virgili, 2017. http://hdl.handle.net/10803/454764.

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Aquesta tesi va dirigida específicament al desenvolupament de poliuretans (PU)s funcionalitzats en la cadena lateral (FPU)s, sintetitzats a partir de diols funcionals que provenen d’àcids grassos i dos diisocianats diferents: el diisocianat d’isoforona (IPDI) i el diisocianat d’hexametilé (HDI). Aquests nous FPUs presenten una amina terciària i grups alquil, al•lil, propargil o la combinació d'aquests en la cadena lateral. Posteriorment els FPUs es modifiquen mitjançant dos mecanismes de post-polimerització basats en enllaços covalents o en enllaços no covalents.En el primer cas, es duen a terme una sèrie de reaccions fotoiniciades d’acoplament tiol-é/í entre el grup al.lil i propargil que presenten els FPUs (formats a partir de IPDI), i tioglicerol. Els hidroxi-PUs obtinguts, exhibeixen una millora del seu caràcter hidrofílic. Alternativament, els FPUs que contenen només una amina terciaria com a grup funcional situat a la cadena lateral del PU, es barregen amb diferents àcids carboxílics per donar una reacció àcid base. Els supramoleculars PUs resultants (SPU)s es caracteritzen per espectroscòpia per a verificar la presència d'enllaços iònics d'hidrogen que uneixen les cadenes de PU mitjançant interaccions fisiques. A més, es demostra la correlació existent entre l'estructura química i les propietats tèrmiques i mecàniques dels materials sintetitzats. Aquests materials presenten prometedores propietats adaptatives. Per exemple, ressalten les bones propietats de regeneració i reciclatge/remodelació, degudes al caràcter reversible de les interaccions físiques. Addicionalment, aquests elastòmers posseeixen una inherent capacitat d’autoreparació, que en termes pràctics es podria veure com una millomillora de la seva sostenibilitat. Finalment, es sintetitzen xarxes de PU que tenen un doble caràcter estructural mitjançant enllaços iònics d'hidrogen dinàmics i entrecreuaments covalents. La variació de la densitat d’entrecreuament covalent introduït per a cada una d’aquestes xarxes, produeixun ajustament sistemàtic de les propietats mecàniques i de la sensibilitat del material a la calor. Aquesta preparació demostra una via simple i eficaç per a la fabricació de poliuretans multifuncionals i l’estratègia seguida també es pot estendre a l'exploració d'altres tipus d'interaccions covalents i no covalents en polímers
Esta tesis está dirigida específicamente al desarrollo de poliuretanos (PU)s funcionalizados en la cadena lateral (FPU)s, sintetizados a partir de dioles funcionales que provienen de ácidos grasos y dos diisocianats diferentes; el diisocianato de isoforona (IPDI) y el diisocianato de hexametileno (HDI). Estos nuevos FPUs presentan una amina terciaria y grupos alquilo, alilo, propargilo o la combinación de éstos en posiciones de cadena lateral. Posteriormente los FPUs se modifican mediante dos mecanismos de post-polimerización basados en enlaces covalentes o en enlaces no covalentes.En el primer caso, se llevan a cabo una serie de reacciones fotoiniciadas de acoplamiento tiol-eno/ino entre el grupo alilo y propargilo que presentan los FPUs (formados a partir de IPDI), y tioglicerol. Los hidroxi-PUs obtenidos, exhiben una mejora de su carácter hidrófilo. Alternativamente, los FPUs que contienen sólo una amina terciaria como grupo funcional situado en la cadena lateral del PU, se mezclan con diferentes ácidos carboxílicos mediante una reacción de ácido base. Los PUs supramoleculares resultantes (SPU)s se caracterizan por espectroscopia para verificar la presencia de enlaces iónicos de hidrógeno que unen las cadenas de PU formando interacciones físicas. Además, se demuestra la correlación existente entre la estructura química y las propiedades térmicas y mecánicas de los materiales sintetizados. Estos materiales presentan prometedoras propiedades adaptativas. Por ejemplo, resaltan las buenas propiedades de regeneración y reciclaje/remodelación, debidas al carácter reversible de las interacciones físicas. Adicionalmente, estos elastómeros poseen una inherente capacidad de autorautorreparación, que en términos prácticos se podría ver como una mejora de su sostenibilidad. Finalmente, se sintetizan redes de PU que tienen un doble carácter estructural mediante enlaces iónicos de hidrógeno dinámicos y entrecruzamientos covalentes. La variación de la densidad de entrecruzamiento covalente introducido para cada una de estas redes produce un ajuste sistemático de las propiedades mecánicas y la sensibilidad del material al calor. Esta preparación demuestra una vía simple y eficaz para la fabricación de poliuretanos multifuncionales.
This Thesis is addressed to the development of side-chain functionalized polyurethanes (FPU)s, with enhanced properties, made from fatty acid-based functional diols and two different diisocyanates; isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI). The novel FPUs present tertiary amine and alkyl, allyl, propargyl moieties or the combination of these, as side-chain positions groups. The FPUs were further modified via two post-polymerization mechanisms based on covalent or non-covalent bonds. In the first case, photoinitiated thiol-ene/yne coupling reaction between allyl, propargyl-functionalized PUs (based on IPDI) and thioglycerol was carried out. Obtained hydroxyl-PUs exhibit different thermal and mechanical properties in comparison with precursor PUs. Moreover, the incorporation of hydroxyl groups leads to PUs with enhanced hydrophilicity. Alternatively, the FPU (based on IPDI) containing only tertiary amine pendant group was mixed with different carboxylic acids in an acid-base reaction. Supramolecular ionic PUs were characterized by spectroscopic tools to verify the presence of ionic hydrogen bond as ionic interaction. Correlation between structure and thermal and mechanical properties was demonstrated. Samples show rapid thermal reversibility and recyclability thanks to the reversible bonds. In addition, elastomeric supramolecular PUs networks were prepared from HDI and aminodiol. The resulting materials exhibit some promising adaptive material properties such as effective energy dissipation upon deformation through unzipping the ionic hydrogen bonding network, combined with good shape-regeneration property and recycling/reshaping capability arising from their recoverable nature. More importantly, the resulting biobased elastomers possess the inherent self-healing ability, which can be seen as an upgrade of their sustainability.A novel thermo-reversible network is constructed by the thiol-ene functionalized polyurethane via dynamic ionic hydrogen bonds and covalent cross-links. By varying the covalent cross-linking density, the mechanical properties and the stimuli-responsive behaviour can be systematically tuned. This synthesis demonstrates a simple and effective pathway to fabricate multifunctional polyurethanes with desired functions.
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Gläske, Mareen [Verfasser]. "Tailoring the Optoelectronic Properties of Carbon Nanotubes : A Comparative Study of Covalent and Non-Covalent Functionalization Approaches / Mareen Gläske." Berlin : Freie Universität Berlin, 2019. http://d-nb.info/1185485910/34.

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Martínez, Carrión Alicia. "The Hydroformylation Reaction: from Covalent to Supramolecular Approaches and Operando Kinetic Studies." Doctoral thesis, Universitat Rovira i Virgili, 2020. http://hdl.handle.net/10803/669292.

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S’ha estudiat la hidrofomilació d΄al·lens 1,1΄-disubstituïts catalitzada per rodi, emprant lligands de tipus bisfosfit amb un centre de regulació allunyat del centre catalític. L'ús de sals de metalls alcalins de BArF com a agents de regulació va fer augmentar la formació d'aldehids β,γ-insaturats (fins a un 60%), demostrant el principi de regulació supramolecular del sistema catalític. La hidroformilació d'octens terminals i interns catalitzada amb cobalt i en presència de Xantphos com lligand ha donat lloc a una alta selectivitat en la formació d'aldehids. El control de la regioselectividad mitjançant la temperatura de la reacció i la proporció constant entre els diferents regioisòmers dels aldehids ens ha portat a postular un procés tàndem d'isomerització-hidroformilació en les condicions optimitzades de reacció. A més, s'ha dut a terme la hidroformilació d'una mescla d'octens, obtenint-se els aldehids amb alta selectivitat i baixa incidència de reaccions secundàries, la qual cosa fa que sigui una ruta plausible a escala industrial. A més, l'ús de lligands regulats supramolecularment amb un centre de regulació allunyat del centre catalític, va permetre la hidroformilació enantioselectiva de aril vinil èters, amb un gran activitat catalítica, regioselectivitat i ràtio enantiomèric (fins a un 88% conversió, >99:1 b/l ràtio, 97:3 er). Estudis de complexació van revelar la formació d'espècies catalítiques inactives i la variació en la distribució de les espècies catalíticamente actives en funció de l'agent de regulació emprat. Finalment es van realitzar estudis cinètics sobre la reacció d'hidroformilació enantioselectiva de l'acetat de vinil emprant lligands bisfosfit regulats mitjançant interaccions supramoleculars. L'ús de l'Anàlisi de Normalització de Temps Variable va permetre esbrinar el pas limitant de la reacció, situant-lo en el començament del cicle catalític. Aquest mètode ha permès obtenir els perfils de reacció en absència dels períodes d'inducció de formació del catalitzador observats durant la reacció.
Se ha descrito la hidroformilación de alenos 1,1΄-disustitutidos catalizada por rodio empleando ligandos de tipo bisfosfito con un centro de regulación alejado del centro catalítico. El uso de sales de BArF de metales alcalinos como agentes de regulación aumentó la formación de aldehídos β,γ-insaturados (hasta un 60%), demostrando el principio de regulación supramolecular del sistema catalítico. La hidroformilación de octenos terminales e internos catalizada con cobalto y en presencia de Xantphos como ligando ha dado lugar a una alta selectividad en la formación de aldehídos. El control de la regioselectividad mediante la temperatura de la reacción y la proporción constante entre los diferentes regioisómeros de los aldehídos nos ha llevado a postular un proceso tándem de isomerización-hidroformilación bajo las condiciones optimizadas de reacción. Además, se ha llevado a cabo la hidroformilación de una mezcla de octenos, obteniéndose los aldehídos con alta selectividad y baja incidencia de reacciones secundarias, lo que la hace una ruta plausible a escala industrial. Además, el uso de ligandos regulados supramolecularmente con un centro de regulación alejado del centro catalítico permitió la hidroformilación enantioselectiva de aril vinil éteres, con una gran actividad catalítica, regioselectividad y ratio enantiomérico (hasta un 88% conversión, >99:1 b/l ratio, 97:3 er). Estudios de complejación revelaron la formación de especies catalíticas inactivas y la variación en la distribución de las especies catalíticamente activas en función del agente de regulación usado. Finalmente se realizaron estudios cinéticos sobre la reacción de hidroformilación enantioselectiva del acetato de vinilo empleando ligandos bisfosfito regulados mediante interacciones supramoleculares. El uso del Análisis de Normalización de Tiempo Variable permitió establecer el paso limitante de la reacción, situándolo en el comienzo del ciclo catalítico y ha permitido la obtención de los perfiles de reacción en ausencia de los periodos de inducción de formación el catalizador observados durante la reacción.
The rhodium-catalyzed hydroformylation of 1,1΄-disubstituted allenes was described employing bisphosphite ligands with a distal regulation site. The use of alkali metal BArF salts as regulation agents enhanced the formation of β,γ-unsaturated aldehydes (up to a 60% increase), proving the supramolecular regulation principle of the catalytic system. Cobalt-catalyzed hydroformylation of terminal and internal octenes in presence of Xantphos as ligand have displayed a high selectivity towards the formation of aldehydes. The control of the regioselectivity by the reaction temperature and the constant ratio in the different regioisomers led us to hypothesize that a tandem isomerization-hydroformylation transformation was taking place under optimized conditions. Furthermore, the hydroformylation of a mixture of octene isomers was reported with excellent aldehyde selectivity and diminished formation of side-products. Overall, the methodology may be suitable for industrial application. Moreover, the use of supramolecularly regulated ligands with distal regulation site enabled the rhodium-catalyzed enantioselective hydroformylation of aryl vinyl ethers, with high catalytic activity, regioselectivity and enantiomeric ratio (up to 88% conv, >99:1 b/l ratio and 97:3 er). Complexation studies revealed the formation of inactive catalytic species and a variation in the distribution of catalytic species based on the regulation agent used. Finally, kinetic studies of the rhodium-catalyzed enantioselective hydroformylation of vinyl acetate with a supramolecularly regulated bisphosphite complex were performed. The use of Variable Time Normalization Analysis allowed for the elucidation of the rate-determining step early in the catalytic cycle. Real kinetic profiles in the absence of catalyst induction periods observed during the reaction were also obtained.
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Singh, Devanshi. "Non-covalent and macromolecular approaches to study protein binding, drug delivery and artificial blood." Thesis, University of Sheffield, 2018. http://etheses.whiterose.ac.uk/22376/.

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To begin with, macromolecules consisting of poly(amido)amine dendrimers(PAMAM), polyglycidol, hyperbranched poly(amido)amine (HYPAM) were synthesized and characterized extensively. Porphyrins were also synthesized, characterized and modified in line with respective studies. Hereafter, surface modified TRIS PAMAM dendrimers and its analogs (hyperbranched polymers, hyperbranched PAMAMs) as potential drug delivery systems were studied with the use of model drugs (Ibuprofen and Porphyrin). Analogs of the model drugs were used to investigate the role of secondary interactions for high drug loading(s). UV-Vis Spectroscopy was utilized for studying and determining the maximum loading of the macromolecules under investigation. Further ahead, non-covalent approaches to improve dendrimer-protein binding were used by introducing amino acid chains as targeting groups on the dendrimer surface. Surface modified carboxylate PAMAM dendrimers were studied for their ability to bind with zinc metallated porphyrin. UV-Vis and Fluorescence Spectroscopy were used for protein binding studies. Lastly, Surface Crosslinked Micelles were synthesized and utilized as artificial blood mimics with an attempt to increase the half-life of encapsulated iron porphyrin acting as the heme mimic with the help of UV-Vis Spectroscopy.
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Squillaci, Bianca. "Approaches to the detection of adducts formed via the covalent binding of reactive metabolites to proteins." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/approaches-to-the-detection-of-adducts-formed-via-the-covalent-binding-of-reactive-metabolites-to-proteins(3b4ccc97-ea77-40d1-bb2b-2c4e70a1424d).html.

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Metabolism of xenobiotic drug molecules can result in the formation of metabolites which are more chemically reactive than the parent drug from which they are derived. These reactive species have the potential to covalently modify biological macromolecules if they are not detoxified. The formation of drug-protein adducts carries a potential risk of clinical toxicities and idiosyncratic adverse drug reactions which can, in severe cases, result in hospitalisation and even death. Current methods for the evaluation of the risk for a drug to cause adverse drug reactions due to drug-protein binding rely on risk factors such as quantitative covalent binding value, structure, dose etc. The objective of this project was to develop methods for the detection of reactive metabolites directly bound to proteins, which could be used in future evaluations of the mechanisms of binding of candidates in drug development. Three compounds known to produce reactive metabolites, acetaminophen, SB-648969 and amodiaquine, were used as tool substrates. In vitro incubations with human liver microsomes and individual cytochrome P450 enzymes (as Supersomes ) were used to produce reactive metabolite species and binding with the incubation proteins evaluated. Analysis of the intact proteins, peptides generated via trypsin digestion of the incubation protein, and amino acids generated via digestion with pronase were evaluated using a combination of LC/MS and LC-MS/MS. Reactive metabolite trapping experiments with glutathione were used to provide information about the likely structure of the bound species and the specificity of binding, and were useful in the development of sensitive targeted precursor ion scanning and multiple reaction monitoring methods. [14C] radiolabelled acetaminophen and SB-649868 were used to assess the quantitative levels of binding (<5% modification of protein in both cases). Radiodetection using accelerator mass spectrometry (AMS) was used to evaluate the stoichiometry of binding and aid the identification of adducted peptides through retention time comparison. Chemical and electrochemical methods were utilised to produce stable solutions of N-acetyl-p-benzoquinone imine (NAPQI) and amodiaquine quinone imine (AQQI), reactive metabolites of acetaminophen and amodiaquine, respectively, which were bound to selected proteins and used as chromatographic and mass spectrometric standards. These methods were used to successfully identify an acetaminophen-modified peptide (T56) of cytochrome P450 CYP2E1. No modified proteins were observed for the SB-649868 incubations, however, examination of the AMS chromatograms for the incubations with acetaminophen and SB-649868 revealed a difference in the stoichiometry of binding, with one modified peptide observed with acetaminophen, and several for the incubations with SB-649868. The detection and identification of drug-protein adducts remains extremely challenging due to the low levels of any adducts observed, which can be exacerbated by binding on multiple sites of a protein; however this project has demonstrated that sensitive and selective LC/MS methods can be successfully developed to identify drug-protein adducts.
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Milovanovic, Milan. "Experimental and theoretical approaches coupled with thermochemistry of reactions in solution and the role of non-covalent interactions." Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAF049.

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Ce manuscrit aborde plusieurs interactions / réactions chimiques importantes se produisant dans la soluton en utilisant la calorimétrie par titrage isothermique (ITC) et la théorie de la densité fonctionnelle statique (DFT). Cette thèse porte son attention notamment sur : l'association de paires de Lewis (frustrées) ((F)LPs), la migration cis du groupe méthyle au sein du pentaméthylmanganèse induit par les phosphines, l'aminolyse de carbènes de Fischer, l'insertion d'alcynes dans des palladacycles, l'affinité de divers donneurs de Lewis à l’hexafluoroisopropanol. L'ITC s'est révélé être une technique expérimentale puissante pour obtenir des données thermochimiques fiables sur les systèmes étudiés. Les calculs statiques DFT-D ont montré une capacité d’estimation correcte des paramètres de réaction thermodynamique lorsque l’influence de la solvatation n’est pas significative. Autrement, lorsque l’influence du solvant est apparente, les calculs ne permettent pas de reproduire les résultats expérimentaux. En plus, les résultats expérimentaux et théoriques révèlent l’existence d’ensembles moléculaires plus grandes dans la solution de FLP, soulignant le rôle des interactions non covalentes
This manuscript adressed several important chemical interactions/reactions taking place in solutuon by using Isothermal Titration Calorimetry (ITC) and static Density Functional Theory (DFT). Namely, this thesis dealt with: association of (frustrated) Lewis pairs ((F)LPs), cis-migration of methyl group within pentamethylmanganese induced by phosphines, aminolysis of Fischer carbenes, insertion of alkynes into palladacycles, affinity of various Lewis donors to hexafluoroisopropanol. The ITC proved to be powerful experimental technique for obteining reliable thermochemical data of sutudied systems. The static DFT-D calculations showed capability for proper estiamtion of thermodynamic reaction parameters when an influence of solvation is not sighnificant. Otherwise, when the influence of solvent is not innocent, the calculations moslty failed to reproduce the experimantal results. In addition, Both the experimantal and therortical results revield existance of larger molecular clusters in solution of FLPs emphasising a role of non-covalent interactions
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Elkerdawy, Ahmed [Verfasser], and Tim [Akademischer Betreuer] Clark. "CADD Optimization by Using Quantum-Mechanical Approaches for a More Accurate Description of Non-Covalent Intermolecular Interactions / Ahmed Elkerdawy. Gutachter: Tim Clark." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2013. http://d-nb.info/1054164487/34.

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Guo, Jingshu. "Structural Analysis of Macromolecular Complexes Using Electrospray Ionization Mass Spectrometry Based Approaches." University of Toledo / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1373036513.

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Creasey, Kate M. "Investigating the roles of arabidopsis polycomb-group genes in regulating flowering time and during plant development by (I) challenging silencing and (II) developing approaches to dissect Pc-G action." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/4025.

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Polycomb-group (Pc-G) proteins regulate homeotic gene silencing associated with the repressive covalent histone modification, trimethylation of histone H3 lysine 27 (H3K27me3). Pc-G mediated silencing is believed to remodel chromatin, rendering target genes inaccessible to transcription factors. Pc-G mediated silencing might result in irreversible changes in chromatin structure, however, there has been little analysis addressing whether Pc-G mediated silencing is reversible. In this work we focused on CURLY LEAF (CLF), the first Pc-G homologue discovered in Arabidopsis. CLF mediated repression of the floral homeotic gene AGAMOUS (AG) was challenged during early and late leaf development. AG was activated by the late leaf promoter, revealing that Pc-G mediated silencing can be overcome in old leaves in the presence of CLF. AG was also activated in young leaf primordia, yet did not persist in older leaves, revealing that transient activation of a Pc-G target is not epigenetically stable. To address the mechanism of Pc-G action within an endogenous environment, the histone dynamics at the APETALA1 (AP1) locus were characterized by Chromatin Immunoprecipitation. Unexpectedly, we found that the activation of AP1 in leaves did not require the removal of H3K27me3, questioning whether H3K27me3 is sufficient to silence. The roles of CLF in leaf and flower development are masked due to partial redundancy with SWINGER (SWN). clf- swn- mutants form a callus-like mass on sterile-tissue culture with no distinguishable plant organs. The role of CLF in regulating flowering time in natural populations of A. thaliana was investigated by complementing clf- mutants with CLF alleles from two accessions. We found that natural variation in CLF did not affect flowering time. To dissect the roles of CLF and SWN in late leaf and flower development, two approaches were developed for targeted expression. Firstly, CLF was introduced into the LhG4/ pOp transactivation system to provide CLF during early plant development. For mosaic analysis, CLF was introduced into the CRE lox recombination system in order to create clf- sectors surrounded by CLF+ SWN+ and CLF+ swn- cells.
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Liebenberg, Liesl Eileen. "Non-covalent immobilisation of a ligand system : a new approach to affinity separation." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53522.

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Thesis (MSc)--Stellenbosch University, 2003.
ENGLISH ABSTRACT: Advances in pharmacology, biochemistry and biotechnology are increasingly dependant upon affinity chromatography as a preferred separation technique for the purification and characterisation of specific biomolecules. In the past few years avidin-biotin technology has been widely and successfully used in the fields of medicine, pharmacy, biology and biochemistry. The avidin-biotin complex (ABC) has been used as a mediator for affinity chromatography, affinity cytochemistry, immunoassay, histopathology, bioaffinity sensors, erosslinking and immobilisation studies. The main reason for the popularity of the ABC and its growing usefulness in biotechnology is the exceptionally high affinity (1015 M-l) and stability of the noncovalent interaction between avidin and biotin. The use of the ABC is broadening as different biotin derivatives and avidin-containing conjugates are becoming commercially available. The aim of this work was to evaluate the usefulness of a plutonic" FI 08 and the ABC conjugate to effect affinity separation. Towards this aim, the adsorption of plutonic" F108 onto hydrophobic polysulphone membrane surfaces was studied. This information was used to determine the theoretical maximum amount of pluronic" FI08 that will adsorb onto a unit surface area of the membrane. It is known that the polypropylene oxide (PPO) centre block ofthe pluronic" F I08 surfactant molecule governs the concentration of pluronic" F I 08 molecules that will adsorb onto a given hydrophobic surface. If the maximum coating concentration of plutonic" FI08 is known, one can assume that the maximum coating concentration of any pluronic derivative, with the same PPO centre block size, will be the same. Adsorption studies were carried out, the Langmuir adsorption isotherm was determined, and subsequently the fractional coating was calculated. The end-groups of plutonic" FI08 were modified as follows and the substituted pluronic was adsorbed onto a membrane that was to act as the solid support matrix in the development of an affinity system: Amino pluronic was synthesised by first tosylating pluronic" FI08, followed by azidation with NaN3 then reduction with LiAI~. The synthesised amino pluronic was then biotinylated using N-hydroxysuccinimide biotin ester. The suitability of this synthetic route was first assessed on a model compound, 2-methoxyethylamine, and validated by NMR (Nuclear Magnetic Resonance) spectroscopy. The synthetic protocol was then used to derivatise the larger pluronic molecule. The affinity system was tested on two different hydrophobic surfaces: polystyrene and polysulphone membranes (PSMs). Avidin-conjugated horseradish peroxidase was obtained and used to interact with the immobilised biotin. The enzymatic reaction of the coupled peroxidase converted the substrate, 2, 2'-azino-di-(3-ethyl-benzthiazoline-6-sulphonic acid) (ABTS) to a coloured product. The colour developed is proportional to the amount of biotin that was immobilised on the hydrophobic surfaces studied. Non-covalent immobilisation of the synthesised biotin-pluronic molecule was successfully obtained onto the hydrophobic polystyrene as well as the polysulphone membrane surfaces.
AFRIKAANSE OPSOMMING: Vooruitgang in die farmakologie, biochemie en biotegnologie word al meer afhanklik van affiniteits chromatografie as die verkose tegniek vir die suiwering en karaterisering van spesifieke biomolekules. Oor die afgelope jare het die avidien-biotien tegnologie homself as baie bruikbaar bewys in die mediese, farmakologiese, biologiese en biochemiese velde. Toepassings waar die avidien-biotien kompleks betrokke was sluit in die toepassing as 'n mediator vir affiniteits chromatografie, affiniteits sitologie, immuno bepalings, histopatologie, bioaffiniteits sensors sowel as kruisbinding en immobiliserings studies en vele meer. Die hoofrede vir die gewildheid van die avidien-biotien kompleks en die groeiende bruikbaarheid in die biotegnologie is die buitengewone hoë affiniteit (l015 M-I ) en stabiliteit van die nie-kovalente interaksie tussen avidien en biotien. Die toepassingsveld van die avidien-biotien kompleks word wyer met die verskeidenheid biotien derivate en avidien-bevattende konjugate wat kommersiëel beskikbaar is. Die doel van die werk wat hier gedokumenteer word is om die bruikbaarheid van Plutonic" FI08 en die avidien-biotien kompleks, vir gebruik in 'n affiniteits chromatografie sisteem, te evalueer. Om hierdie doel te bereik is die adsorpsie van Pluronic" FI08 aan hidrofobiese polisulfoon membraan oppervlaktes bestudeer. Die eksperimentele data wat gegenireer is, is gebruik om die teoretiese maksimum hoeveelheid Pluronic wat per eenheids oppervlakte membraan adsorbeer te bepaal. Dit is reeds bekend dat die polipropileen (PPO) middel blok van die Pluronic emulgant die konsentrasie van die geadsorbeerde Pluronic molekules op 'n gegewe hidrofobiese oppervlakte bepaal. Indien die maksimum bedekkingskonsentrasie VIr maksimum oppervlakbedekking van Plutonic" FI08 bekend is, kan teoreties aanvaar word dat die bedekkingskonsentrasie vir enige Pluronic derivaat met dieselfde grootte PPO blok dieselfde sal wees. Adsorpsiestudies was uitgevoer om die Langmuir adsorpsie isoterm te bepaal. Daaropvolgend was die fraksionele bedekking bereken. Amino-pluronic was gesintetiseer deur die eindpunte van Pluronic te derivatiseer. Hierdie Pluronic derivaat was gevolglik geadsorbeer aan 'n membraan wat gedien het as die soliede oppervlakte vir die ontwikkeling van 'n affiniteits chromatografie sisteem. Amino-pluronic was gesintetiseer deur Pluronic eers te tosileer en daarna te asideer met NaN3 en laastens te reduseer met LiAI~. Die produk was gebiotinileer deur gebruik te maak van N-hidroksisuksinimied-biotien-ester. Die bruikbaarheid van hierdie sintetiese roete is eers bepaal deur van 'n model verbinding, 2-metoksiëtielamien, gebruik te maak en dit met behulp van KMR (Kern Magnetiese Resonans) spektroskopie te karakteriseer. Die affiniteits sisteem is getoets op twee verskillende hidrofobiese oppervlaktes naamlik polistireen en polisulfoon membraan oppervlaktes. Avidien gekonjugeerd met 'n peroksiedase ensiem is gebruik om met die geïmmobiliseerde biotien te assosieer. Die ensiematiese reaksie van die gekoppelde peroksiedase het die substraat 2, 2' -azino-di-(3-etiel-benzthiazolien-6-sulfoonsuur) (ABTS) omgesit na 'n gekleurde produk, waar dit teenwoordig is. 'n Reeks wasstappe is gebruik om die gemodifiseerde peroksidase ensiem wat nie aan die hidrofobiese oppervlakte gekoppel nie, weg te spoel. Hierdeur is die mate van binding aan die hirofobiese oppervlakte gekwantifiseer deur die kleur te kwantifiseer wat ontwikkelomdat die kleurontwikkeling direk proporsioneel is aan die hoeveelheid peroksidase wat nog aan die membraan gekoppel is. Nie-kovalente immobilisasie van die gesintetiseerde biotien-pluronic molekule is suksesvolop beide die hidrofobiese polistireen oppervlakte sowel as die polisulfoon membraan verkry.
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Books on the topic "Covalent approaches"

1

Yaghi, Omar M., Christian S. Diercks, and Markus J. Kalmutzki. Reticular Chemistry: A Practical Approach for Metal-Organic Frameworks and Covalent Organic Frameworks. Wiley & Sons, Limited, John, 2023.

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Book chapters on the topic "Covalent approaches"

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Sanders, Jeremy K. M. "Dynamic Combinatorial Approaches to Catenanes." In From Non-Covalent Assemblies to Molecular Machines, 147–49. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2010. http://dx.doi.org/10.1002/9783527632817.ch10.

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Balbo Block, Marco A., Christian Kaiser, Anzar Khan, and Stefan Hecht. "Discrete Organic Nanotubes Based on a Combination of Covalent and Non-Covalent Approaches." In Topics in Current Chemistry, 89–150. Berlin, Heidelberg: Springer Berlin Heidelberg, 2005. http://dx.doi.org/10.1007/b98167.

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Siringo, F. "Molecular Ordering in Covalent Solids: A Simple Lattice Model." In Many-body Approaches at Different Scales, 59–73. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-72374-7_6.

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Whitesides, George M., Eric E. Simanek, and Christopher B. Gorman. "Approaches to Synthesis Based on Non-Covalent Bonds." In Chemical Synthesis, 565–88. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-009-0255-8_25.

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Marzo, Leyre, and José Alemán. "Recent approaches in asymmetric non-covalent organo-photocatalysis." In Photochemistry, 283–302. Cambridge: Royal Society of Chemistry, 2022. http://dx.doi.org/10.1039/9781839167676-00283.

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Gavezzotti, A., and G. Filippini. "Non-Covalent Interactions in Organic Crystals, and the Calibration of Empirical Force Fields." In Computational Approaches in Supramolecular Chemistry, 51–62. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-1058-7_3.

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Sgobba, Vito, Christian Ehli, and Dirk M. Guldi. "Chapter 15. Covalent Approaches towards Multifunctional Carbon-Nanotube Materials." In Nanoscience & Nanotechnology Series, 549–612. Cambridge: Royal Society of Chemistry, 2011. http://dx.doi.org/10.1039/9781849732956-00549.

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Zhu, Youlong, Yinghua Jin, and Wei Zhang. "Chapter 8. Emerging Covalent Organic Framework and Linear Polymer (COF–LP) Composites: Synthetic Approaches and Applications." In Hybrid Metal-Organic Framework and Covalent Organic Framework Polymers, 344–74. Cambridge: Royal Society of Chemistry, 2021. http://dx.doi.org/10.1039/9781839163456-00344.

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Cigler, Marko, Tuan-Anh Nguyen, and Kathrin Lang. "CHAPTER 5.2. Genetic Code Expansion Approaches to Introduce Artificial Covalent Bonds into Proteins In Vivo." In Oxidative Folding of Proteins, 399–420. Cambridge: Royal Society of Chemistry, 2018. http://dx.doi.org/10.1039/9781788013253-00399.

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Mirabella, D., R. Deza, and C. M. Aldao. "A Simple Approach to Surface States in Covalent Crystals." In Condensed Matter Theories, 201–6. Boston, MA: Springer US, 1992. http://dx.doi.org/10.1007/978-1-4615-3352-8_19.

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Conference papers on the topic "Covalent approaches"

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Ward, Richard A., and Richard Lonsdale. "Abstract 4638: Predictive computational approaches to guide the covalent targeting of cysteine residues in drug discovery." In Proceedings: AACR Annual Meeting 2018; April 14-18, 2018; Chicago, IL. American Association for Cancer Research, 2018. http://dx.doi.org/10.1158/1538-7445.am2018-4638.

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Silva, Victor Hugo Malamace da, and Glaucio Braga Ferreira. "Chemical interaction study between xanthate ligand and lead (II) using NBO, EDA and QTAIM analysis." In VIII Simpósio de Estrutura Eletrônica e Dinâmica Molecular. Universidade de Brasília, 2020. http://dx.doi.org/10.21826/viiiseedmol2020159.

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As a useful flotation agent, the xanthate ligand, O-alkyldithiocarbonates, has been used by different countries by its easy and inexpensive synthesis. More recently papers explored many different applications using this ligand within a complex of several metals cation. In order to study the proprieties of the lead (II) complex with such ligand, the object of this work is to provide a better understanding of the Pb-S bond using different theoretical approaches as NBO, EDA and QTAIM analysis and the influence caused by the different alkyl groups of the ligand. By an optimized structure, the NBO showed that the Pb-S is mainly composed by p orbital of the lead and by the p lone pair of the sulfur atom. The calculation with different alkyl groups highlights that the presence of a larger hydrocarbon chain provides a higher contribution of the s orbital of the lead atom to the interaction. Through the EDA analysis, the interaction between ligand and metal has the predominance of an electrostatic character. The size of the alkyl group has an impact on the value of both covalent and electrostatic character, making the interaction more covalent, due to a higher presence of an electronic density on sulfur atom. This density can be evaluated by the topological study of the QTAIM analysis, which enhances the fact that the charge over the sulfur atom gets higher when using a larger alkyl group for the xanthate ligand.
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Chung, C. L., K. Nguyen, S. Lyonnais, S. Streiff, S. Campidelli, L. Goux-Capes, J. P. Bourgoin, A. Filoramo, Wolfgang Fritzsche, and Frank Bier. "DNA Linked To Single Wall Carbon Nanotubes: Covalent Versus Non-Covalent Approach." In DNA-BASED NANODEVICES: International Symposium on DNA-Based Nanodevices. AIP, 2008. http://dx.doi.org/10.1063/1.3012293.

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Doll, Kenneth M., Glenn L. Heise, Malgorzata Myslinska, and Brajendra K. Sharma. "Formulation of a Biobased Gear Oil Utilizing Boron Technology." In ASME/STLE 2012 International Joint Tribology Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/ijtc2012-61036.

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A new additive was produced from a natural oil and boron. The synthesis involves the use of the epoxidized form of soybean oil which then undergoes a catalytic ring opening to produce the additive material. Due to their remaining triacylglycerol structure, the products are highly compatible with bio-based lubricants and due to their covalent boron attachments, show effective properties for the reduction of wear. Some performance examples: Using a traditional Falex 4-ball wear test, the scar diameter observed in a soybean oil lubricant could be reduced from 0.61 mm to 0.41 mm by the inclusion of 1% or the additive. A second generation additive, while not as effective at reducing wear, was able to increase the oxidation onset temperature of soybean oil under pressurized oxygen by 14 °C. Next, these additives were tested in a formulation of biobased gear oil composed of heat treated soybean oil and synthetic esters. In the best formulation, these additives were able to surpass the oxidation onset of a gear oil that was formulated with commercially available additives, while giving nearly as good of performance by wear scar analysis. This oxidation onset value, of 258 °C, approaches that of off-the-shelf gear oils. Overall, these new additives are strong performers which can be made using simple chemistry. Their properties combined with their high biobased content are valuable assets in the search for biobased lubricants and gear oils.
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Borsari, Chiara, Erhan Keles, Jacob McPhail, Alexander Schäfer, Rohitha Sriramaratnam, Martina De Pascale, Matthias Gstaiger, John Burke, and Matthias P. Wymann. "Abstract 1377: Volume scanning, a rational approach to covalent PI3Kα inhibitors." In Proceedings: AACR Annual Meeting 2021; April 10-15, 2021 and May 17-21, 2021; Philadelphia, PA. American Association for Cancer Research, 2021. http://dx.doi.org/10.1158/1538-7445.am2021-1377.

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Acharya, Sarthak, Shailesh Singh Chouhan, and Jerker Delsing. "Realization of Embedded Passives using an additive Covalent bonded metallization approach." In 2019 22nd European Microelectronics and Packaging Conference & Exhibition (EMPC). IEEE, 2019. http://dx.doi.org/10.23919/empc44848.2019.8951871.

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Sabet, Seyed Morteza, Hassan Mahfuz, Andrew C. Terentis, and Javad Hashemi. "A New Approach to the Synthesis of Carbon Nanotube-Polyhedral Oligomeric Silsesquioxane (POSS) Nanohybrids." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-50925.

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To date, the functionalization of carbon nanotubes (CNTs) with Polyhedral Oligomeric Silsesquioxanes (POSS) has become one of the most intensively explored methods to produce CNT-based nanostructure composite materials. In this study, a simple and effective synthesizing method has been reported to prepare a nanohybrid material consisting of multi-walled carbon nanotubes (MWCNT) and aminopropylisobutyl-POSS. The approach is based on covalent bonding between CNTs and POSS molecules. Characterization of the as-received materials as well as the POSS-treated CNTs has been performed. Raman and Fourier transform infrared spectroscopic analyses verify the covalent grafting of POSS onto CNT walls through the formation of amide bonds. TEM studies reveal the attachment of relatively high amount of POSS to the CNT walls in POSS-treated product. TGA observations suggest that the presence of relatively high amount of POSS in MWCNT-POSS product is responsible for the thermal stability of CNTs at temperature range of RT–200 °C. The resulting nanohybrids with improved functionality and thermal stability would be good candidates as reinforcing materials for compatible polymer matrices.
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Asadi, Ehsan, Ali Karimzade, and Mehrdad Farid. "Investigation of the Fundamental Frequency of Double Walled Carbon Nanotubes Using Molecular Mechanics Approach by an Averaging Van Der Waals Forces Modeling." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-62962.

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Carbon nanotubes have received a lot of attention since their introduction in 1991 because of novel properties that show substantial promises for use in many applications. Their usage depends on the strength of our knowledge of their properties. In this work, molecular mechanics approach is used to study the mechanical properties of multi-wall carbon nanotubes. In particular this paper investigates fundamental frequency of double walled carbon nanotubes. Carbon nanotubes are big and long molecules that can be regarded as mechanical structures. In modeling of multi-walled carbon nanotubes, two distinct atomic bonds are required to be modeled, i.e. covalent bonds between the neighboring carbon atoms in the same layer and Van der Waals bonds between close atoms in neighboring layers. In this approach, for modeling of each wall; covalent bonds are modeled by beam joints such that atoms are considered to be concentrated masses at the ends. Interactions of neighboring walls that are mainly due to Van der Waals forces are treated to be truss rods in modeling. The most challenging aspect of modeling is to define truss rod properties as they are highly nonlinear. We utilized an averaging method for finding truss rod properties. Finite Element Method is employed to obtain Fundamental frequencies. Results are compared to available researches and a close agreement is observed. Results indicate that by increasing aspect ratio, fundamental frequency of double walled nanotubes decrease. In addition, double walled carbon nanotubes have higher fundamental frequencies at clamp-clamp in comparison to clamp-free condition; however, this difference becomes negligible as aspect ratio increases.
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Bhatnagar, Promod K., Poonam Gupta, and Laxman Singh. "Calculation of optical parameters for covalent binary alloys used in optical memories/solar cells: a modified approach." In Symposium on Integrated Optics, edited by Gail J. Brown and Manijeh Razeghi. SPIE, 2001. http://dx.doi.org/10.1117/12.429429.

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Fono-Tamo, R. S., Jen Tien-Chien, and O. Bhila. "A Comparative Assessment of the Structural, Elastic and Electronic Properties of Nb3Pt and NbPt3 Phases Through First-Principles Study." In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-86911.

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Two phases of the Nb-Pt system namely Nb3Pt and NbPt3 have been studied using first principles approach in CASTEP. Structural, elastic and electronic properties of the concerned binary alloys were determined and examined against each other. Although both alloys have the same structure, it was observed that the percentage difference in the change of lattice parameters varied. Nb3Pt exhibited a 0.073% change while NbPt3 had a 14.809% change making Nb3Pt more stable structurally than NbPt3. The elastic properties showed that both binaries are ductile materials but NbPt3 proved to be more ductile than Nb3Pt based on Born, Pugh’s and Frantsevich’s criteria. Through the electronic properties, both binaries were proven to be conducting and their bonding nature seen as a combination of ionic metallic and covalent bond.
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