Application Of Transition Metal Reagents And Catalysts In Carbohydrate Synthesis

Homogeneous catalysis is an important strategy for the synthesis of high-valued chemicals. L. Brandsma has carefully selected and checked the experimental procedures illustrating the catalytic use of copper, nickel, and palladium compounds in organic synthesis. All procedures are on a preparative scale, make economic use of solvents and catalysts, avoid toxic substances and have high yields.

The continually growing contribution of transition metal chemistry to synthetic organic chemistry is, of course, widely recognized. Equally well known is the difficulty in keeping up-to-date with the multifarious reactions and procedures that seem to be spawned at an ever-increasing rate. These can certainly be summarized on the basis of reviews under the headings of the individual transition metals. More useful to the bench organic chemist, however, would be the opposite type of concordance based on the structural type of the desired synthetic product. This is the approach taken in the present monograph, which presents for each structural entity a conspectus of the transition metal-mediated processes that can be employed in its production. The resulting comparative survey should be a great help in devising the optimum synthetic approach for a particular goal. It is presented from an essentially practical viewpoint, with detailed direc tions interspersed in the Houben-Weyl style. The wide scope of the volume should certainly encourage synthetic organic chemists to utilize fully the range and versatility of these transition metal-mediated processes. This will certainly be a well-thumbed reference book! R. A. RAPHAEL Cambridge University v Preface In recent years an enormous amount of work has been done on the catalysis of organic reactions by various transition metal species and on the organic reactivity of organo-transition-metal compounds.

Im Laufe der vergangenen 35 Jahre wurden unzahlige Synthesewege entwickelt, bei denen Ubergangsmetallkomplexe entweder als Reagenzien oder als Katalysatoren fungieren. Dieses Buch bietet besonders denjenigen Synthesechemikern interessante und moderne Einblicke, die bisher noch nicht mit den vielfaltigen Moglichkeiten der Organometallchemie mit Ubergangsmetallen vertraut sind. Zu wichtigen ubergangsmetallkatalysierten Reaktionen werden Anwendungsbeispiele diskutiert. (01/00)

This book focuses on the drug discovery and development applications of transition metal catalyzed processes, which can efficiently create preclinical and clinical drug candidates as well as marketed drugs. The authors pay particular attention to the challenges of transitioning academically-developed reactions into scalable industrial processes. Additionally, the book lays the groundwork for how continued development of transition metal catalyzed processes can deliver new drug candidates. This work provides a unique perspective on the applications of transition metal catalysis in drug discovery and development – it is a guide, a historical prospective, a practical compendium, and a source of future direction for the field.

Carbohydrates are synthetically challenging molecules with vital biological roles in all living systems. To better understand the biological functions of this fundamentally important class of molecules, novel methodologies are urgently needed in two different directions: building block synthesis and selective glycosylation. During my Ph.D. study, I developed two different methodologies for building block synthesis, which could simplify the assembly of oligosaccharides.Differentiation of hydroxy groups on the carbohydrate is usually considered challenging as a result of the almost identical chemical environment. 1,2-trans diols are even more difficult to deal with compared to 1,2-cis diols. In my first project, I developed a method for regio- and stereo-selective OH carbene insertion together with my collaborator. Under very mild conditions, a series of 1,2-trans diols can be selectively functionalized. The regioselectivity originated from interactions between substrates and transition-metal catalysts, while the stereochemistry came from intramolecular proton delivery. The newly introduced moiety can work as a protection group, function group for the glycoconjugate mimic synthesis, or participate in the following glycosylation reactions and impact the anomeric selectivity. Inspired by the regio-selectivity of first projects, I developed another transition metal-catalyzed reaction, which could successfully epimerize one hydroxyl group in 1,2-trans diols, thus many rare sugars can be accessed easily starting from readily available common sugars. Compared to the traditional route, the method I developed can simplify the synthesis significantly and is more environmentally friendly. Synthesis of aminosugars through direct amination of 1,2-trans diols is also investigated. Bromodomain (BRD) is an evolutionarily conserved protein-protein interaction module that can recognize and bind acetylated lysine residues in histones and many other proteins. BRD4 protein, which is considered a transcriptional factor and epigenetic regulator, can bind to acetylated histone and recruit protein complexes to stabilize the binding of RNA polymerase II to histone. The dysregulation of BRD4 can cause cancer and other diseases such as immune and inflammatory diseases. Because of this, the BRD4 protein has been long considered an important therapeutic target. In the third project, I worked on the development of tissue-selective BRD4 degraders, aiming to provide a novel therapy for prostate cancer. By attaching tissue-selective ligands to BRD4 degraders, we successfully achieved selectivity among different cell lines, which proved our initial hypothesis. The tri-functional degraders will be tested in vivo in the future.

In many fields, most notably medicine and molecular biology, the understanding of the structure and function of carbohydrates and glycoconjugates remains vital. This new volume contains critical reviews covering the latest findings in both chemical and biological sciences, and demonstrates the interdisciplinary nature of modern carbohydrate research. This book addresses diverse applications that continue to be major challenges for carbohydrate chemists. The book starts with a review of Gérard Descotes contribution to the field as a pioneer of French modern carbohydrate chemistry. Green nanocatalytic oxidation of free sugars, photosensitive glycomacrocycles, the application of disaccharides in supramolecular chemistry, recent advances in the radiation chemistry of polysaccharides, and the cell wall pectic rhamnogalacturonan II, an enigma in plant glycobiology are just some of the diverse topics presented in Volume 45. This set of reports will certainly benefit any researcher who wishes to learn about the latest developments in the carbohydrate field.

Catalysts play a crucial role in the path towards the transformation of organic compounds. This book describes the recent development of metal-based catalysis in organic synthesis. Applications of various catalysts to interesting organic transformations are discussed. It covers important organic reactions such as cyclohexane oxidation under different energy stimuli, use of Pd-nanoparticles for carbonylation of aniline, ammoximation of methyl ethyl ketone by Ni-modified TS-1 and carbozincation of substituted 2-alkynylamines. This book will be a useful reference for researchers in the field of catalysis, organic chemistry and materials science. It is also intended to attract the attention of researchers with an industrial interest.