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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.
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Poet and Peer. (Paperback)
Aide Hamilton, A.D. Hamilton
|
R777
R670
Discovery Miles 6 700
Save R107 (14%)
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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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