The Experts below are selected from a list of 200592 Experts worldwide ranked by ideXlab platform
Stephen F. Martin - One of the best experts on this subject based on the ideXlab platform.
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multicomponent mannich type Assembly Process for generating novel biologically active 2 arylpiperidines and derivatives
ChemInform, 2015Co-Authors: Simon Hardy, Stephen F. MartinAbstract:Novel pyrrolidino- and isoxazolidino-fused 2-arylpiperidines are prepared utilizing a 4-component Mannich-type Assembly Process followed by [3 + 2] dipolar cycloaddition.
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multicomponent mannich type Assembly Process for generating novel biologically active 2 arylpiperidines and derivatives
Tetrahedron, 2014Co-Authors: Simon Hardy, Stephen F. MartinAbstract:A multicomponent, Mannich-type Assembly Process commencing with commercially available bromobenzaldehydes was sequenced with [3+2] dipolar cycloaddition reactions involving nitrones and azomethine ylides to generate collections of fused, bicyclic scaffolds based on the 2-arylpiperidine subunit. Use of the 4-pentenoyl group, which served both as an activator in the Mannich-type reaction and a readily-cleaved amine protecting group, allowed sub-libraries to be prepared through piperidine N-functionalization and cross-coupling of the aryl bromide. A number of these derivatives displayed biological activities that had not previously been associated with this substructure. Methods were also developed that allowed rapid conversion of these scaffolds to novel, polycyclic dihydroquinazolin-2-ones, 2-imino-1,3-benzothiazinanes, dihydroisoquinolin-3-ones and bridged tetrahydroquinolines.
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application of a sequential multicomponent Assembly Process huisgen cycloaddition strategy to the preparation of libraries of 1 2 3 triazole fused 1 4 benzodiazepines
ACS Combinatorial Science, 2012Co-Authors: James R. Donald, Rebekah R. Wood, Stephen F. MartinAbstract:A strategy featuring a multicomponent Assembly Process followed by an intramolecular azide–alkyne dipolar (Huisgen) cycloaddition was implemented for the facile synthesis of three different 1,2,3-triazolo-1,4-benzodiazepine scaffolds. A diverse library of 170 compounds derived from these scaffolds was then created through N-functionalizations, palladium-catalyzed cross-coupling reactions, and several applications of α-aminonitrile chemistry.
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libraries of 2 3 4 6 7 11b hexahydro 1h pyrido 2 1 a isoquinolin 2 amine derivatives via a multicomponent Assembly Process 1 3 dipolar cycloaddition strategy
ACS Combinatorial Science, 2012Co-Authors: Brett A Granger, Kyosuke Kaneda, Stephen F. MartinAbstract:A Mannich-type multicomponent Assembly Process/1,3-dipolar cycloaddition strategy has been developed for the rapid and efficient construction of a parent tetrahydroisoquinoline fused isoxazolidine scaffold, which was subsequently functionalized using well-established protocols to access a diverse 70-membered library of novel 2,3,4,6,7,11b-hexahydro-1H-pyrido[2,1-a]isoquinoline-2-amine derivatives.
Shuichi Hiraoka - One of the best experts on this subject based on the ideXlab platform.
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Multiple Pathways in the Self-Assembly Process of a Pd4L8 Coordination Tetrahedron
2018Co-Authors: Tomoki Tateishi, Tatsuo Kojima, Shuichi HiraokaAbstract:The self-Assembly of a Pd418 coordination tetrahedron (Tet) from a ditopic ligand, 1, and palladium(II) ions, [PdPy*4]2+ (Py* = 3-chloropyridine), was investigated by a 1H NMR-based quantitative approach (quantitative analysis of self-Assembly Process, QASAP), which allows one to monitor the average composition of the intermediates not observed by NMR spectroscopy. The self-Assembly of Tet takes place mainly through three pathways and about half of the Tet structures were produced through the reaction of a kinetically produced Pd3L6 double-walled triangle (DWT) and 200-nm-sized large intermediates (IntL). In two of the three pathways, the leaving ligand (Py*), which is not a component of Tet, catalytically assisted the self-Assembly. Such a multiplicity of the self-Assembly Process of Tet suggests that molecular self-Assembly takes place on an energy landscape like a protein-folding funnel
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quantitative analysis of the self Assembly Process of a pd12 l24 coordination sphere
Chemistry-an Asian Journal, 2017Co-Authors: Shumpei Kai, Tatsuo Kojima, Taro Shigeta, Shuichi HiraokaAbstract:The self-Assembly Process of a Pd12L24 sphere was revealed by a quantitative approach (quantitative analysis of self-Assembly Process: QASAP) quantifying all the substrates, the products, and the observable intermediates, indicating that the Pd12L24 sphere is produced through several pathways. Firstly, PdnL2n (n = 6, 8, and 9), which are perfectly closed structures smaller than the Pd12L24 sphere, and a mixture of intermediates not observed by NMR (Int) were produced. Next, the sphere was assembled from intra-/intermolecular reaction of a certain class of Int (path A) and from the coordination of free pyridyl groups in Int to the Pd(II) center of PdnL2n (n = 6, 8, and 9) (path B). While capping the free pyridyl groups in Int with Pd(II) ions perfectly inhibited the sphere formation, the addition of free L to Int accelerated the formation of the sphere.
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a reaction model on the self Assembly Process of octahedron shaped coordination capsules
Physical Chemistry Chemical Physics, 2017Co-Authors: Yoshihiro Matsumura, Shuichi Hiraoka, Hirofumi SatoAbstract:Herein, the self-Assembly Process of an octahedron-shaped coordination capsule was analyzed based on a master equation approach using a reaction network model. This model was found to adequately reproduce the overall experimentally observed time evolutions and enabled us to trace the real-time evolution of transient intermediates, ranging from milli-second to hours. The time evolution of the distribution of individual intermediates species was obtained; a few linear-oligomers located near the reactant were produced at first, followed by an explosive increase in several types of intermediates. All of them were then consolidated into a few species just before the formation of the final product. A long-lived [Pd618Py]12+ is a key compound, which acts as a kinetic trap in the reaction dynamics.
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rate determining step in the self Assembly Process of supramolecular coordination capsules
Chemical Science, 2014Co-Authors: Yuya Tsujimoto, Tatsuo Kojima, Shuichi HiraokaAbstract:An in-depth understanding of the self-Assembly Process at the molecular level is crucial in both biological and materials science fields. However, such research is scarce due to the difficulty in monitoring a great deal of fragmentary species that are transiently produced in the Process. We present a novel method for investigating the self-Assembly Process of supramolecular coordination assemblies by following the time variation of the average composition of the fragmentary species, which was indirectly determined by spectroscopy. With this method, we found that the final stage is the rate-determining step of the self-Assembly of an octahedron-shaped coordination capsule, and that the relative energy barrier of each step is controllable by modifying the chemical structure of the building blocks.
Martin Zimmermann - One of the best experts on this subject based on the ideXlab platform.
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A new fabrication and Assembly Process for ultrathin chips
IEEE Transactions on Electron Devices, 2009Co-Authors: Joachim N. Burghartz, Horst D. Rempp, Wolfgang Appel, Martin ZimmermannAbstract:A new ultrathin chip fabrication and Assembly Process, consisting of a preProcess module Chipfilm and a postProcess module Pick, Crack, and Place, is presented. In contrast to the established wafer thinning technique, the preProcessed wafer substrates are prepared with extremely narrow buried cavities beneath the chip areas at a well-defined distance from the wafer surface, thus precisely defining the chip thickness a priori. After CMOS integration on those dedicated wafer substrates, chips are detached from the wafer surface by etching trenches at the chip edges into the buried cavities and breaking of residual anchors by mechanical force in the postProcess. The feasibility of the new Process is demonstrated through a mixed-signal circuit having 38 000 digital and 2700 analog transistors, showing full functionality within specifications for 20-mum-thin chips even under a bending stress of up to 110 MPa.
Jiang Zhibin - One of the best experts on this subject based on the ideXlab platform.
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computer aided block Assembly Process planning in shipbuild ing based on rule reasoning
Chinese Journal of Mechanical Engineering (English Edition), 2008Co-Authors: Zhang Zhiying, Li Zhen, Jiang ZhibinAbstract:Computer-aided block Assembly Process planning based on rule-reasoning are developed in order to improve the Assembly efficiency and implement the automated block Assembly Process planning generation in shipbuilding.First,weighted directed liaison graph (WDLG) is proposed to represent the model of block Assembly Process according to the characteristics of Assembly relation, and edge list (EL) is used to describe Assembly sequences.Shapes and Assembly attributes of block parts are analyzed to determine the Assembly position and matched parts of parts used frequently. Then,a series of Assembly rules are generalized,and Assembly sequences for block are obtained by means of rule reasoning.Final,a prototype system of computer-aided block Assembly Process planning is built.The system has been tested on actual block,and the results were found to be quite efficiency.Meanwhile,the fundament for the automation of block Assembly Process generation and integration with other systems is established.
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approach on automation method of hull Assembly Process based on rule reasoning
Journal of Shanghai Jiaotong University, 2007Co-Authors: Jiang ZhibinAbstract:The modeling of hull Assembly Process and Assembly sequence planning was developed.An extended weighted directed liaison graph was proposed to represent the model of hull Assembly according to the characteristics of Assembly relation of hull.Meanwhile an edge list was used to represent the Assembly sequences.Shape and Assembly features of hull parts were analyzed to conclude the Assembly elements and matched parts of common hull parts.Automation generation of Assembly sequences for hull parts was(achieved) by means of rule reasoning.A prototype system of Assembly sequences automation generation was built.
Joachim N. Burghartz - One of the best experts on this subject based on the ideXlab platform.
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A new fabrication and Assembly Process for ultrathin chips
IEEE Transactions on Electron Devices, 2009Co-Authors: Joachim N. Burghartz, Horst D. Rempp, Wolfgang Appel, Martin ZimmermannAbstract:A new ultrathin chip fabrication and Assembly Process, consisting of a preProcess module Chipfilm and a postProcess module Pick, Crack, and Place, is presented. In contrast to the established wafer thinning technique, the preProcessed wafer substrates are prepared with extremely narrow buried cavities beneath the chip areas at a well-defined distance from the wafer surface, thus precisely defining the chip thickness a priori. After CMOS integration on those dedicated wafer substrates, chips are detached from the wafer surface by etching trenches at the chip edges into the buried cavities and breaking of residual anchors by mechanical force in the postProcess. The feasibility of the new Process is demonstrated through a mixed-signal circuit having 38 000 digital and 2700 analog transistors, showing full functionality within specifications for 20-mum-thin chips even under a bending stress of up to 110 MPa.
