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Isotope Effects in Chemistry and Biology. Edited by Amnon Kohen and Hans-Heinrich Limbach

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Isotope Effects in Chemistry and
Edited by Amnon
Kohen and HansHeinrich Limbach.
CRC Press/Taylor &
Francis, Boca Raton
2005. 1128 pp.,
$ 229.95.—ISBN
The editors, both well known for their
own contributions using isotope effects
in their respective research areas, have
succeeded in putting together a group of
people who represent the diversity of
applications of isotope effects in chemistry and biology quite well. The book
consists of 42 chapters, which are authored by the leading experts in their
fields. Every chapter includes plenty of
references to secondary literature for
further reading.
There are some chapters that
explain the underlying theory and principles, such as the contribution by Bigeleisen, who—based on his experience of
more than 60 years research on isotope
effects (his first paper on the calculation
of equilibrium constants for isotopic
exchange reactions dates from 1947)—
explains the theoretical basis of isotope
effects from his perspective. The chapter
by Wolfsberg explains quantummechanical calculations of isotope
effects within the transition-state
theory (TST), while the chapter by
Truhlar takes it further into the variational transition-state theory (VTST)
and multidimensional tunneling. Kuznetsov and Ulstrup describe the theory
of isotope effects related to proton
transfer (PT) and electron transfer
(ET) in condensed matter, while Northrop describes the effect of (hydrostatic)
pressure on kinetic isotope effects.
Other aspects of isotope effects in
condensed matter, such as vapor pressure, molar volume, and compressibility
of liquids, solids, and solutions, are
covered in a contribution by van Hook.
Aoki extends the discussion of isotope
effects to ice, and discusses the results of
hydrogen-bond symmetrization in the
solid state and its effects on Raman and
infrared spectra at high pressure.
Isotope effects on spectroscopic
properties are also discussed in other
chapters. Del Bene explains the effect of
anharmonicity on the IR and NMR
properties of hydrogen-bonded complexes, while Mielke and Sobczyk focus
on IR spectroscopy and vibrational isotope effects in hydrogen-bonded systems and the sources of anomalous H/D
isotope effects. Hippler and Quack
explain the principles and applications
of isotope-selective infrared spectroscopy and intramolecular dynamics.
Limbach and co-authors describe in
detail NMR studies of hydrogen-bond
isotope effects. They show how liquidand solid-state NMR techniques can be
used to study isotope effects of strong
hydrogen bonds, which represent
models for the transition states of
proton-transfer reactions with high barriers. Perrin addresses the problem of
single- and double-well potentials, and
demonstrates how hydrogen-bonded
systems can be investigated by measurement of the pKa value, NMR chemical
shifts, or coupling constants, while
Hansen focuses on intramolecular
hydrogen bonds and describes longrange as well as through-space isotope
effects. Low-barrier hydrogen bonds
and their characterization by isotope
effects are analyzed by Frey.
Atmospheric chemistry is the topic
of two chapters, which describe nonmass-dependent isotope effects, including effects on the isotopologues of
various atmospheric gases, which
covers most isotope effects in the stratosphere. The second paper on isotope
effects in the atmosphere deals with
isotope effects in the troposphere and
with effects on interstellar media.
Kinetic isotope effects of short-lived
radionuclides such as 11C or 18F are
+ 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
covered, as well as the possibilities that
arise from using muonium, the ultralight hydrogen isotope. Enrichment and
separation techniques for isotopomers
are compared in the chapter by Ishida
and Fujii, which discusses various methods, together with the relevant mathematical background. Chlorine isotope
effects are described in a chapter by
Koch on the role of the internal-return
mechanism, and in one by Paneth that
deals with biological systems. Kinetic
isotope effects in proton-transfer reactions are analyzed in two contributions,
and effects on nucleophilic reactions are
discussed in a third one. Secondary
isotope effects are discussed in a chapter
by Hengge, and solvent isotope effects
in one by Quinn.
Computer simulations of isotope
effects in enzyme catalysis often use a
combination of quantum mechanics
(QM) and molecular mechanics (MM)
calculations to accommodate the need
for an accurate description of the reacting fragments, while the size of the
surrounding protein/solvent region prohibits the use of an electronic-structure
method and is taken into account by a
molecular-mechanics force field. Warshel and co-authors describe several
simulations and kinetic isotope effect
studies of enzymes, including potential
problems, while a second paper by
Sutcliffe and Scrutton uses kinetic isotope effects as probes to study enzymatic hydrogen tunneling.
Enzymes and the use of kinetic
isotope effects for various research
aspects are a significant part of the
book. The chapter by Schowen introduces the topic of enzyme catalysis, and
Cleland explains the analysis of the
mechanisms, with several examples,
including chorismate mutase, malic
enzyme, and oxalate decarboxylase.
The dependence of isotope effects in
enzyme catalysis on the substrate and
pH is analyzed by Cook.
Classic examples such as MMO or
P450 must, of course, be included in a
book on this subject. Lipscomp contributes a separate chapter on sMMO and
MMOB, while Fitzpatrick includes cytochrome P450 in his article on enzymecatalyzed
Schwartz and Plapp describe the use of
kinetic isotope effects in the investigation of alcohol dehydrogenases, while
Angew. Chem. Int. Ed. 2006, 45, 6420 – 6421
Silverman discusses solvent hydrogen isotope effects in reactions catalyzed by
carbonic anhydrase. The transfer of
hydrogen atoms in enzymatic reactions
is addressed in the chapter by HammesSchiffers on proton-coupled electron
transfer, while Kohen uses kinetic isotope
effects as a probe to study hydrogen
tunneling in enzymes. The mechanism of
CH bond cleavage by enzymes such as
coenzyme B12 or lipoxygenase is discussed
by Siebrand and Smedarchina, while
Klinman describes enzymatic oxygen
(18O) activation, and Schramm discusses
isotope effects on enzymatic binding.
The book can be recommended as a
reference source for people working in
the field of isotope effects, as well as a
textbook for advanced students who
want to deepen their understanding of
the usefulness of isotope effects.
Thomas Strassner
Physikalische-Organische Chemie
Technische Universit8t Dresden
DOI: 10.1002/anie.200585384
Reagents for Glycoside,
Nucleotide, and Peptide Synthesis
Handbook of
Reagents for
Organic Synthesis.
Edited by David
Crich. John Wiley &
Sons, Hoboken
2005. 786 pp.,
E 125.00.—ISBN
The book Reagents for Glycoside,
Nucleotide and Peptide Synthesis,
edited by David Crich, is, of course, a
handbook, as is clear from the series
title Handbook of Reagents for Organic
Synthesis. However, is it not also much
more than that? More about that later.
As is stated in the introduction,
although a third of the factual information about the reagents and their applications in this book has been taken from
the Encyclopedia of Reagents for
Angew. Chem. Int. Ed. 2006, 45, 6420 – 6421
Organic Synthesis (EROS), which was
published in 1995, the greater part of it
comes from publications that have
appeared in the last ten years. Thus,
the book gives the reader an up-to-date
survey of the recent literature on
reagents that are important for the
synthesis of glycosides, nucleosides, and
The descriptions of how the reagents
are used are presented in separate short
chapters, which together achieve a successful blending of minireview and textbook. In accordance with this textbook
character, in many cases the chapters
explain the reaction mechanisms or the
details of how the reagents work, while
they also indicate their range of applications and their limitations. The way in
which the chapters on individual
reagents are structured in this book
reminds one of Organisch-Chemische
Experimentierkunst, edited by G. Hilgetag, but unlike that work it does not
subdivide the reagents into separate
groups for the synthesis of glycosides,
nucleosides, and peptides. It was a clever
decision to treat the reagents in alphabetical order, as it avoided the need for
many repetitions and cross-references to
other chapters. Otherwise they would
certainly have been necessary, because
in many cases the same protecting group
techniques and linking methods are
used in the synthesis of all three classes
of biomolecules. This way of combining
the descriptions within and across the
different classes of biomolecules, for
example when describing the synthesis
of fragments that are common to glycopeptides and peptidoglycans, also means
that it is no longer even possible to
group the reagents according to the
synthetic requirements within individual
classes of biomolecules.
The book is addictive! From the
moment when the reader, as an enthusiastic natural products chemist, first
opens the book, it is almost impossible
to stop turning the pages or becoming
absorbed in reading one or another of
the chapters. At least, that is how it
affected this reviewer, on first picking
up the book at the Wiley stand during an
interval at a symposium.
Part of the bookCs fascination is that
there are so many different ways of
using it. Firstly, it is a valuable reference
source for students working for their
degree at graduate, master, or doctorate
level. To illustrate that, let us take the
example of 1,3-dicyclohexylcarbodiimide. Under this heading the up-andcoming scientist can find physical data
about the reagent, and information
about its solubility, storage requirements, handling, and additional safety
precautions. He or she will also find
practical advice about the use of the
compound, in the form of a short
laboratory protocol. That is followed
by information about the main applications of the reagent, with the relevant
literature references. All this information about dicyclohexylcarbodiimide is
collected together within three pages.
Secondly, a chemist can use the
handbook to build up an index of
methods. However, for this purpose it
would be desirable to have the reagents
also grouped according to areas of
application, such as oxidation, reduction, glycosylation, carboxyl group activation, etc.
The usefulness of the book would be
further increased if a future edition
could be provided with such an enlarged
subject index, which would require an
amount of work that seems manageable.
In that way the handbook could also be
used as the basis for a set of lecture
notes on the broad subject: “modern
aspects of the synthesis of oligosaccharides, oligopeptides, and oligonucleotides”. If that were done, in view of the
wealth of available material there would
be a wide range of possibilities regarding
the choice of main topics and the title of
the teaching package. The emphasis
might be on methods, on mechanisms,
or on purely synthetic aspects. Such
teaching packages based on this book
would be especially valuable because of
the many up-to-date literature references.
In summary, this handbook provides
a wealth of up-to-date, well arranged,
and helpfully structured material, which
can be used in many different ways. It is
a must for every natural products chemist working on synthetic aspects.
Christian Vogel
Institut fAr Chemie
Abteilung Organische Chemie
Universit8t Rostock (Germany)
+ 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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chemistry, hans, effect, heinrich, edited, amnon, limbach, biologya, kohei, isotopes
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