The Experts below are selected from a list of 61542 Experts worldwide ranked by ideXlab platform
Qixiang Guo - One of the best experts on this subject based on the ideXlab platform.
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combining chiral aldehyde catalysis and transition metal catalysis for enantioselective α allylic alkylation of amino acid esters
Journal of the American Chemical Society, 2019Co-Authors: Lei Chen, Mingjing Luo, Fang Zhu, Wei Wen, Qixiang GuoAbstract:A chiral aldehyde is rationally combined with a Lewis acid and a transition metal for the first time to form a triple catalytic system. This cocatalytic system exhibits good catalytic activation and stereoselective-control abilities in the asymmetric α-allylation reaction of N-unprotected amino acid esters and allyl acetates. Optically active α,α-disubstituted α-amino acids (α-AAs) are generated in good yields (up to 87%) and enantioselectivities (up to 96% ee). Preliminary mechanism investigation indicates that the chiral aldehyde 3f acts both as an organocatalyst to activate the amino acid ester via the formation of a Schiff base, and as a ligand to facilitate the nucleophilic Attack Process by coordinating with π-allyl Pd(II) species.
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Combining Chiral Aldehyde Catalysis and Transition-Metal Catalysis for Enantioselective α‑Allylic Alkylation of Amino Acid Esters
2019Co-Authors: Lei Chen, Mingjing Luo, Fang Zhu, Wei Wen, Qixiang GuoAbstract:A chiral aldehyde is rationally combined with a Lewis acid and a transition metal for the first time to form a triple catalytic system. This cocatalytic system exhibits good catalytic activation and stereoselective-control abilities in the asymmetric α-allylation reaction of N-unprotected amino acid esters and allyl acetates. Optically active α,α-disubstituted α-amino acids (α-AAs) are generated in good yields (up to 87%) and enantioselectivities (up to 96% ee). Preliminary mechanism investigation indicates that the chiral aldehyde 3f acts both as an organocatalyst to activate the amino acid ester via the formation of a Schiff base, and as a ligand to facilitate the nucleophilic Attack Process by coordinating with π-allyl Pd(II) species
Lei Chen - One of the best experts on this subject based on the ideXlab platform.
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combining chiral aldehyde catalysis and transition metal catalysis for enantioselective α allylic alkylation of amino acid esters
Journal of the American Chemical Society, 2019Co-Authors: Lei Chen, Mingjing Luo, Fang Zhu, Wei Wen, Qixiang GuoAbstract:A chiral aldehyde is rationally combined with a Lewis acid and a transition metal for the first time to form a triple catalytic system. This cocatalytic system exhibits good catalytic activation and stereoselective-control abilities in the asymmetric α-allylation reaction of N-unprotected amino acid esters and allyl acetates. Optically active α,α-disubstituted α-amino acids (α-AAs) are generated in good yields (up to 87%) and enantioselectivities (up to 96% ee). Preliminary mechanism investigation indicates that the chiral aldehyde 3f acts both as an organocatalyst to activate the amino acid ester via the formation of a Schiff base, and as a ligand to facilitate the nucleophilic Attack Process by coordinating with π-allyl Pd(II) species.
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Combining Chiral Aldehyde Catalysis and Transition-Metal Catalysis for Enantioselective α‑Allylic Alkylation of Amino Acid Esters
2019Co-Authors: Lei Chen, Mingjing Luo, Fang Zhu, Wei Wen, Qixiang GuoAbstract:A chiral aldehyde is rationally combined with a Lewis acid and a transition metal for the first time to form a triple catalytic system. This cocatalytic system exhibits good catalytic activation and stereoselective-control abilities in the asymmetric α-allylation reaction of N-unprotected amino acid esters and allyl acetates. Optically active α,α-disubstituted α-amino acids (α-AAs) are generated in good yields (up to 87%) and enantioselectivities (up to 96% ee). Preliminary mechanism investigation indicates that the chiral aldehyde 3f acts both as an organocatalyst to activate the amino acid ester via the formation of a Schiff base, and as a ligand to facilitate the nucleophilic Attack Process by coordinating with π-allyl Pd(II) species
Z. Zhan - One of the best experts on this subject based on the ideXlab platform.
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Characterizing Honeypot-Captured Cyber Attacks: Statistical Framework and Case Study
arXiv: Cryptography and Security, 2016Co-Authors: Z. ZhanAbstract:Rigorously characterizing the statistical properties of cyber Attacks is an important problem. In this paper, we propose the {\em first} statistical framework for rigorously analyzing honeypot-captured cyber Attack data. The framework is built on the novel concept of {\em stochastic cyber Attack Process}, a new kind of mathematical objects for describing cyber Attacks. To demonstrate use of the framework, we apply it to analyze a low-interaction honeypot dataset, while noting that the framework can be equally applied to analyze high-interaction honeypot data that contains richer information about the Attacks. The case study finds, for the first time, that Long-Range Dependence (LRD) is exhibited by honeypot-captured cyber Attacks. The case study confirms that by exploiting the statistical properties (LRD in this case), it is feasible to predict cyber Attacks (at least in terms of Attack rate) with good accuracy. This kind of prediction capability would provide sufficient early-warning time for defenders to adjust their defense configurations or resource allocations. The idea of "gray-box" (rather than "black-box") prediction is central to the utility of the statistical framework, and represents a significant step towards ultimately understanding (the degree of) the {\em predictability} of cyber Attacks.
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1Characterizing Honeypot-Captured Cyber Attacks: Statistical Framework and Case Study
2016Co-Authors: Z. ZhanAbstract:Abstract—Rigorously characterizing the statistical properties of cyber Attacks is an important problem. In this paper, we propose the first statistical framework for rigorously analyzing honeypot-captured cyber Attack data. The framework is built on the novel concept of stochastic cyber Attack Process, a new kind of mathematical objects for describing cyber Attacks. To demonstrate use of the framework, we apply it to analyze a low-interaction honeypot dataset, while noting that the framework can be equally applied to analyze high-interaction honeypot data that contains richer information about the Attacks. The case study finds, for the first time, that Long-Range Dependence (LRD) is exhibited by honeypot-captured cyber Attacks. The case study confirms that by exploiting the statistical properties (LRD in this case), it is feasible to predict cyber Attacks (at least in terms of Attack rate) with good accuracy. This kind of prediction capability would provide sufficient early-warning time for defenders to adjust their defense configurations or resource allocations. The idea of “gray-box ” (rather than “black-box”) prediction is central to the utility of the statistical framework, and represents a significant step towards ultimately understanding (the degree of) the predictability of cyber Attacks. Index Terms—Cyber security, cyber Attacks, stochastic cy-ber Attack Process, statistical properties, long-range dependence (LRD), cyber Attack prediction I
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Characterizing honeypot-captured cyber Attacks: Statistical framework and case study
IEEE Transactions on Information Forensics and Security, 2013Co-Authors: Z. Zhan, M Xu, S. XuAbstract:Rigorously characterizing the statistical properties of cyber Attacks is an important problem. In this paper, we propose the first statistical framework for rigorously analyzing honeypot-captured cyber Attack data. The framework is built on the novel concept of stochastic cyber Attack Process, a new kind of mathematical objects for describing cyber Attacks. To demonstrate use of the framework, we apply it to analyze a low-interaction honeypot dataset, while noting that the framework can be equally applied to analyze high-interaction honeypot data that contains richer information about the Attacks. The case study finds, for the first time, that long-range dependence (LRD) is exhibited by honeypot-captured cyber Attacks. The case study confirms that by exploiting the statistical properties (LRD in this case), it is feasible to predict cyber Attacks (at least in terms of Attack rate) with good accuracy. This kind of prediction capability would provide sufficient early-warning time for defenders to adjust their defense configurations or resource allocations. The idea of “gray-box” (rather than “black-box”) prediction is central to the utility of the statistical framework, and represents a significant step towards ultimately understanding (the degree of) the predictability of cyber Attacks.
S. Xu - One of the best experts on this subject based on the ideXlab platform.
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Characterizing honeypot-captured cyber Attacks: Statistical framework and case study
IEEE Transactions on Information Forensics and Security, 2013Co-Authors: Z. Zhan, M Xu, S. XuAbstract:Rigorously characterizing the statistical properties of cyber Attacks is an important problem. In this paper, we propose the first statistical framework for rigorously analyzing honeypot-captured cyber Attack data. The framework is built on the novel concept of stochastic cyber Attack Process, a new kind of mathematical objects for describing cyber Attacks. To demonstrate use of the framework, we apply it to analyze a low-interaction honeypot dataset, while noting that the framework can be equally applied to analyze high-interaction honeypot data that contains richer information about the Attacks. The case study finds, for the first time, that long-range dependence (LRD) is exhibited by honeypot-captured cyber Attacks. The case study confirms that by exploiting the statistical properties (LRD in this case), it is feasible to predict cyber Attacks (at least in terms of Attack rate) with good accuracy. This kind of prediction capability would provide sufficient early-warning time for defenders to adjust their defense configurations or resource allocations. The idea of “gray-box” (rather than “black-box”) prediction is central to the utility of the statistical framework, and represents a significant step towards ultimately understanding (the degree of) the predictability of cyber Attacks.
Larry Greenblatt - One of the best experts on this subject based on the ideXlab platform.
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official certified ethical hacker review guide for version 7 1 ec council certified ethical hacker ceh
2012Co-Authors: Steven Defino, Larry GreenblattAbstract:OFFICIAL CERTIFIED ETHICAL HACKER REVIEW GUIDE: FOR VERSION 7.1 is a valuable resource to help you pursue the most recognized, respected hacking certification in the world. As experienced instructors of the International Council of Electronic Commerce Consultants (EC-Council), the authors draw on firsthand experience training top-caliber information security professionals for success on the council's Certified Ethical Hacker (CEH) exam. The only exam review guide officially endorsed by the EC-Council, this proven resource focuses on the core concepts that are covered on the newest certification course (version 7.1), as well as a wide array of useful learning tools, including chapter objectives, step-by-step tutorials, "Try it Out" exercises and challenges, , group discussion topics, short lab examples, and practice exam questions and answers with explanations.The official CEH course teaches the latest hacking techniques, exploits, automated programs, and defensive recommendations, preparing students to audit organizations' protection of their information assets through a deep understanding of the methodologies and tools of the Attack Process. This official CEH Exam review guide can be used to either preview and prepare for this comprehensive course or review afterwards to prepare for the challenging exam. It is the perfect complement that gives any student a real advantage toward success with this certification.
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official certified ethical hacker review guide for version 7 1
2012Co-Authors: Steven Defino, Larry GreenblattAbstract:OFFICIAL CERTIFIED ETHICAL HACKER REVIEW GUIDE: FOR VERSION 7.1 is an invaluable resource to help you pursue the most recognized, respected hacking certification in the world. As experienced instructors of the International Council of Electronic Commerce Consultants (EC-Council), the authors draw on firsthand experience training top-caliber information security professionals for success on the council's Certified Ethical Hacker (CEH) exam. The only exam review guide officially endorsed by the EC-Council, this proven resource includes detailed content based on the newest certification course (version 7.1), as well as a wide array of useful learning tools, including chapter objectives, step-by-step tutorials, "Try it Out" exercises and challenges, Exam Essentials features, group discussion topics, short lab examples, and a full practice exam with questions, answers, and explanations. The official CEH course teaches the latest hacking techniques, exploits, automated programs, and defensive recommendations, preparing students to audit organizations' protection of their information assets through a deep understanding of the methodologies and tools of the Attack Process. This official CEH Exam review guide can be used to either preview and prepare for this comprehensive course or review afterwards to prepare for the challenging exam. It is the perfect compliment that gives any student a real advantage toward success with this certification.