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Considering the high level of our knowledge concerning covalent bond formation in the organic chemistry of molecules, our understanding of the principles involved in organic solid design is almost in its infancy. While chemists today are able to synthesize organic molecules of very high complexity using sophisticated methods of preparation, they lack general approaches enabling them to reliably predict organic crystalline or solid structures from molecular descriptors - no matter how simple they are. On the other hand, nearly all the organic matter surrounding us is not in the single-molecule state but aggregated and condensed to form liquid or solid molecular assemblages and structural arrays giving rise to the appearances and properties of organic compounds we usually observe. Obviously, the electrical, optical or magnetic properties of solid organic materials that are important requirements for future technologies and high-tech applications, as well as the stability and solubility behavior of a medicament depend on the structure of the molecule and the intramolecular forces, but even more decisively on the intermolecular forces, i. e. the packing structure of the molecules to which a general approach is lacking. This situation concerned ]. Maddox some years ago to such a degree that he described it as "one of the continuing scandals in the physical sciences" [see (1998) Nature 335:201; see also Ball, P. (1996) Nature 381:648]. The problem of predicting organic solid and crystal structures is very dif- cult.
One of the most active areas of contemporary organic chemistry involves the search for new catalysts that borrow concepts, strategies and even components from enzymes but yet are not found in nature. Such artificial enzymes not only give enormous insights into the mechanisms of enzyme catalysis but also offer the potential for catalyzing a wide range of chemical reactions with no counterpart in nature. Several approaches have been taken in the deVelopment of new catalysts, some based on biological methods and others on synthetic techniques. Site directed mutagenesis has allowed the direct replacement of amino acids in an enzyme with resulting changes in stability, selectivity and mechanism. Recent developments have shown that even non-natural amino acids can be incorporated into proteins and also that enzymes can function effectively in organic solvents. A different biological route to artificial enzymes has exploited the immune system and its ability to generate millions of antibodies to a given antigen. Novel antigens have been designed to mimic the transition states of chemical reactions. Antibodies elicited against these antigens thus contain an active site that is complementary to transition state structure and can potentially catalyze target reactions. A broad range of reactions can now be 6 catalyzed using the method with rate accelerations reaching 10 compared to the control reactions. Protein engineering and catalytic antibodies represent complex solutions to the problem of artificial enzymes. Their complexity is however their principal limitation.
One of the most active areas of contemporary organic chemistry involves the search for new catalysts that borrow concepts, strategies and even components from enzymes but yet are not found in nature. Such artificial enzymes not only give enormous insights into the mechanisms of enzyme catalysis but also offer the potential for catalyzing a wide range of chemical reactions with no counterpart in nature. Several approaches have been taken in the deVelopment of new catalysts, some based on biological methods and others on synthetic techniques. Site directed mutagenesis has allowed the direct replacement of amino acids in an enzyme with resulting changes in stability, selectivity and mechanism. Recent developments have shown that even non-natural amino acids can be incorporated into proteins and also that enzymes can function effectively in organic solvents. A different biological route to artificial enzymes has exploited the immune system and its ability to generate millions of antibodies to a given antigen. Novel antigens have been designed to mimic the transition states of chemical reactions. Antibodies elicited against these antigens thus contain an active site that is complementary to transition state structure and can potentially catalyze target reactions. A broad range of reactions can now be 6 catalyzed using the method with rate accelerations reaching 10 compared to the control reactions. Protein engineering and catalytic antibodies represent complex solutions to the problem of artificial enzymes. Their complexity is however their principal limitation.
It is well accepted that progress in biological and biochemical researches is based mainly on a better understanding of life processes on a molecular level. For this, modern chemical techniques for structural elucidation even of sophisticated biomolecules and theoretical and mechanistic considerations involving biological macromolecules help the understanding of structure-function relations, metabolic processes, molecular and cellular recognition and the reproduction of life. On the other hand, controlled manipulation of the struc ture of biological macromolecules and the synthesis of well designed biomimetic models are the basic tools used in bio organic chemistry, a field at the -border line between classical biochemistry and classical organic chemistry. For this, increas ing number of chemists and biochemists are studying simple synthetic molecules as models of enzyme action, ion transport across membranes and in general receptor-substrate inter action. This new series, Bioorganic Chemistry Frontiers, will at tempt to bring together critical reviews on the progress in this field. In this second volume of the series, six different active domains are covered and are presented to stress the diversity and scope of bioorganic chemistry. They include the design of artificial nucleases (Corey, Zuckermann, and Schultz), molecu lar tweezers (Zimmerman), hydrolytic cleavage with metal complexes (Chin, Banaszczyk, Jubian, Kim, and Maejen), dif ferent aspects of molecular recognition (Hamilton), supramole cular assemblies and functional models of membranes and enzymes (Murakami and Kikuchi) and the concept ofmolecu lar topology (Sauvage and Dietrich). Each subject uses a "molecular" language common to the chemist, the biologist, and the pharmacologist."
Considering the high level of our knowledge concerning covalent bond formation in the organic chemistry of molecules, our understanding of the principles involved in organic solid design is almost in its infancy. While chemists today are able to synthesize organic molecules of very high complexity using sophisticated methods of preparation, they lack general approaches enabling them to reliably predict organic crystalline or solid structures from molecular descriptors - no matter how simple they are. On the other hand, nearly all the organic matter surrounding us is not in the single-molecule state but aggregated and condensed to form liquid or solid molecular assemblages and structural arrays giving rise to the appearances and properties of organic compounds we usually observe. Obviously, the electrical, optical or magnetic properties of solid organic materials that are important requirements for future technologies and high-tech applications, as well as the stability and solubility behavior of a medicament depend on the structure of the molecule and the intramolecular forces, but even more decisively on the intermolecular forces, i. e. the packing structure of the molecules to which a general approach is lacking. This situation concerned ]. Maddox some years ago to such a degree that he described it as "one of the continuing scandals in the physical sciences" [see (1998) Nature 335:201; see also Ball, P. (1996) Nature 381:648]. The problem of predicting organic solid and crystal structures is very dif- cult.
Title: Poet and Peer.Publisher: British Library, Historical Print EditionsThe British Library is the national library of the United Kingdom. It is one of the world's largest research libraries holding over 150 million items in all known languages and formats: books, journals, newspapers, sound recordings, patents, maps, stamps, prints and much more. Its collections include around 14 million books, along with substantial additional collections of manuscripts and historical items dating back as far as 300 BC.The GENERAL HISTORICAL collection includes books from the British Library digitised by Microsoft. This varied collection includes material that gives readers a 19th century view of the world. Topics include health, education, economics, agriculture, environment, technology, culture, politics, labour and industry, mining, penal policy, and social order. ++++The below data was compiled from various identification fields in the bibliographic record of this title. This data is provided as an additional tool in helping to insure edition identification: ++++ British Library Hamilton, A d; 1880. 3 vol.; 8 . 12640.k.4.
This is an EXACT reproduction of a book published before 1923. This IS NOT an OCR'd book with strange characters, introduced typographical errors, and jumbled words. This book may have occasional imperfections such as missing or blurred pages, poor pictures, errant marks, etc. that were either part of the original artifact, or were introduced by the scanning process. We believe this work is culturally important, and despite the imperfections, have elected to bring it back into print as part of our continuing commitment to the preservation of printed works worldwide. We appreciate your understanding of the imperfections in the preservation process, and hope you enjoy this valuable book.
Title: Poet and Peer.Publisher: British Library, Historical Print EditionsThe British Library is the national library of the United Kingdom. It is one of the world's largest research libraries holding over 150 million items in all known languages and formats: books, journals, newspapers, sound recordings, patents, maps, stamps, prints and much more. Its collections include around 14 million books, along with substantial additional collections of manuscripts and historical items dating back as far as 300 BC.The GENERAL HISTORICAL collection includes books from the British Library digitised by Microsoft. This varied collection includes material that gives readers a 19th century view of the world. Topics include health, education, economics, agriculture, environment, technology, culture, politics, labour and industry, mining, penal policy, and social order. ++++The below data was compiled from various identification fields in the bibliographic record of this title. This data is provided as an additional tool in helping to insure edition identification: ++++ British Library Hamilton, Aide; 1880. 3 vol.; 8 . 12640.k.4.
Title: Poet and Peer.Publisher: British Library, Historical Print EditionsThe British Library is the national library of the United Kingdom. It is one of the world's largest research libraries holding over 150 million items in all known languages and formats: books, journals, newspapers, sound recordings, patents, maps, stamps, prints and much more. Its collections include around 14 million books, along with substantial additional collections of manuscripts and historical items dating back as far as 300 BC.The GENERAL HISTORICAL collection includes books from the British Library digitised by Microsoft. This varied collection includes material that gives readers a 19th century view of the world. Topics include health, education, economics, agriculture, environment, technology, culture, politics, labour and industry, mining, penal policy, and social order. ++++The below data was compiled from various identification fields in the bibliographic record of this title. This data is provided as an additional tool in helping to insure edition identification: ++++ British Library Hamilton, A d; 1880. 3 vol.; 8 . 12640.k.4.
This is an EXACT reproduction of a book published before 1923. This IS NOT an OCR'd book with strange characters, introduced typographical errors, and jumbled words. This book may have occasional imperfections such as missing or blurred pages, poor pictures, errant marks, etc. that were either part of the original artifact, or were introduced by the scanning process. We believe this work is culturally important, and despite the imperfections, have elected to bring it back into print as part of our continuing commitment to the preservation of printed works worldwide. We appreciate your understanding of the imperfections in the preservation process, and hope you enjoy this valuable book.
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