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Book Review Modern Pulsed and Continuous-Wave Electron Spin Resonance. Edited by L. Kevan and M. K. Bowman

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objectives. For the technologist it would have been sensible
to limit the treatment to the most important points and to
elucidating the main principles, while on the other hand a
book dealing generally with the biochemistry of pesticides
would be expected to give a full and accurate account of the
current state of knowledge. One would expect that a book
published in 1990 should include an appropriate coverage of
the literature on pesticide mechanisms and other recent developments, some aspects of which are treated in numerous
publications, including some good reviews. This task has not
been adequately addressed here.
Of the six chapters on insecticides the first three are devoted to organophosphates, carbamates and organochlorine
compounds. These groups are dealt with clearly and comprehensively, with the emphasis on applications. Each of these
chapters includes a list of compounds compiled with the
practitioner in mind (although consisting only of selected
examples); the lists for the organophosphates and carbamates are arranged according to the crop plants to be protected, whereas that for the organochlorine compounds concentrates on the harmful insect species (why the difference?).
The next chapter is a detailed treatment of the pyrethroids.
Whereas much space is devoted to the older classical insecticides, more recent developments are only treated marginally,
even though some of these have already joined the “classical” category; it is exactly here that some sound information
should have been provided for the novice practitioner.
Whereas at least eight pages have been devoted to the benzoylphenylureas, the growth regulators are given only a
single page. Thus, these sections, which appear under the
title “Other Insecticides and Similar Compounds”, are
unsatisfactory as regards their content. The delta-endotoxin
from Bacillus thuringiensis is only briefly mentioned in the
epilogue, even though it is achemical rather than a biological
agent; even the author himself refers to this as “unfortunate”. The chapters on insecticides conclude with a discussion of resistance. The current trend towards integrated
pest management (IPM) would undoubtedly have justified
being given a chapter to itself, especially since this monograph is intended also for newcomers to the area of modern
insect control methods.
The three chapters on fungicides cover the subject in a very
general way. The older products are over-represented at the
expense of more recent ones. For example, mercury compounds are treated exhaustively, whereas the melanin
biosynthesis inhibitors, which have the interesting property
of preventing the fungal hypha from penetrating into the
leaves, are omitted entirely. The information on the chemistry, metabolism, and mode of action of fungicides is well
presented. In contrast the biological information is of such a
general nature that there is a risk of misunderstandings. In
Table 10.1, which lists the molds according to the manner in
which they exist on the host plant, it is wrongly stated, for
example, that true honeydew molds live under the leaf cuticle. In the same table the phenylamides are not listed against
the Oomycetes in Group 1 A. In the chapter on systemic
fungicides the comments on resistance need to be treated
with some caution, and should be qualified by noting that
saturation treatments are not recommended as a way of
overcoming resistance to fungicides, and that mixtures of
phenylamides with carbendazim have no anti-resistance effect. The discussion of negatively correlated cross-resistance
fails to mention the only example of commercial importance,
namely the benzimidazoles and the phenylcarbamates,
which are used to combat Botrytis.
In the part on herbicides the introductory chapter is concerned with definitions of relevant terms, such as uptake and
Angew. Chem. Int. Ed. Engl. 3i (1992) No. 2
transport in the plant, selectivity, persistence, methods of
application, and herbicide mixtures. Some of the newer techniques, such as the use of herbicide safeners, should have
been mentioned in this introductory chapter. In Table 13.1
the herbicides are classified from the standpoints of agronomy (for Group 1) and of biochemical mechanisms (for
Groups 2 and 3). Here a uniform method of classification
was desirable; this could have been achieved by integrating
Table 14.1 with Table 13.1. The general biological aspects
are treated comprehensively in three chapters, one on leaf
herbicides and two on soil herbicides. The author also covers
a few of the more recent developments from the applications
standpoint, such as the introduction of the sulfonylureas.
However, for many of the classes of herbicides the treatment
of mechanisms is inadequate. For some products, such as
photosynthesis inhibitors of the PS-I1 type (Fig. 14.2), the
mode of action has now been clarified, and the basic principle should have been described in this book, also listing a few
of the most important literature references. The mechanism
of resistance to triazines (p. 454) is also known. It is also
known that herbicide safeners (not “antidotes”) essentially
function by activating enzymes that metabolize the herbicides (pp. 468, 483). On page 395 the structure of phosphoenolpyruvate is shown incorrectly.
The literature citations are complete for the period up to
about ten years ago. While it is true that some more recent
original papers are also listed, the selection does not seem to
be representative. Instead of citing original papers it would
have been more useful to give references to recent review
articles or more advanced reading, even to the extent of
excluding all but these; this applies especially to students,
who are regarded by the author as an important section of
the potential readership.
Included as an appendix is a list of some of the pesticides
mentioned in the book, including a few of their trade names.
No claims are made regarding the completeness of the list.
What is the use of a list that is incomplete in every respect?
It is of equally little value to all types of readers, whether
practitioners or academic researchers.
In summary, the book cannot be recommended in its
present from. It is not a textbook, but neither is it an up-todate review of the biochemistry of pesticides. The structure
of the book is not systematic enough for students, and the
material is not adequately presented from a teaching standpoint. It does not represent the current state of knowledge.
Recent developments in the pesticides area receive too little
attention, or are even omitted altogether.
Edith Ebert, Hartmut Kayser, Theodor Staub
Ciba-Geigy AG
Base1 (Switzerland)
Modern Pulsed and Continuous-Wave Electron Spin Resonance. Edited by L. Kevan and M . K. Bowman. Wiley,
Chichester, 1990. 435 pp., hardcover f. 74.35.-ISBN 0471-50274-X
The introduction of pulsed Fourier transform (FT) techniques, the trend towards using very high external magnetic
fields, and the development of multidimensional methods
(2D, 3D etc.) have brought about an enormous upsurge of
activity in NMR spectroscopy during the past decade. Electron spin resonance (ESR) is a technique closely related to
NMR, and it was evident from the start that its development
must follow a similar course. However, it has taken a long
time for this to happen, mainly due to problems of a techni-
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243
cal nature. Nevertheless, Kevan and Schwartz edited an initial monograph on this theme as early as 1979 (Time Domain
Electron Spin Resonance, Wiley). In recent years great
strides have been made in this area, with regard to both
instrumentation and technique. The most striking evidence
of this is that since 1988 a commercial FT-ESR spectrometer
has been on the market. Although several review articles
dealing with this area have appeared, there has not until now
been a monograph devoted especially to the techniques and
instrumentation of pulsed ESR. The work reviewed here fills
that gap.
The book contains six chapters dealing with particular
aspects of pulsed ESR; a further three chapters are concerned with novel CW-ESR techniques, in which the
microwave power is not pulsed (CW = continuous-wave). In
the first chapter M. K. Bowman gives a good introduction to
electron spin-echo (ESE) and FT-ESR spectroscopy and the
historical development of these techniques. The resemblances to NMR and the differences are clearly pointed out,
and the technical problems are discussed. As well as the
instrumentation and data processing, some applications that
are essentially inaccessible to CW-ESR are indicated. In
Chapter 2 A. Schweiger reports on methodology and instrumentation of pulsed ESR, in particular with regard to the
nuclear modulation effect observed in the electron spin-echo
(ESEEM) for solids. An excellent introduction to the basic
principles of this method is followed by an account of various special techniques for simplifying and interpreting spectra, most of which have been developed in the author’s laboratory. A fairly long section is again devoted to the instrumentation, with a description of the important task of developing the probe-heads for pulsed ESR measurements. In
Chapter 5 L. Kevan looks at the ESEEM effect from a different standpoint. He does not go into so much detail regarding
the technique and instrumentation, emphasizing instead the
methods for analyzing data in the time and frequency domains, and he draws attention to several new types of chemical applications. The two chapters devoted to ESEEM
(Chapters 2 and 5 ) thus complement each other very nicely,
and they show the importance of the method for measuring
the electron-nuclear hyperfine couplings in solids, a technique which is complementary to the ENDOR (electron-nuclear double resonance) method. The latter method, which is
already well-known from its use in CW spectroscopy, is the
subject of Chapter 4, in which A. Grupp and M. Mehring
give an excellent introduction to pulsed ENDOR (in which
both the microwave and the radiofrequency power are
pulsed). As well as the “classical” methods of Mims and
Davies, some newer pulse sequences that have been developed by these authors or by Schweiger et al. are also described. Applications up to now have been confined to studies of solids. Chapter 3, by J. Gorcester, G. Millhauser, and
J. Freed, is devoted to studies of molecular motions in condensed phases, especially in liquids, for which it appears that
pulsed ESR is eminently suitable. The majority of the fascinating new methods described by these authors are two-dimensional ESE or FT-ESR techniques, some of which will
already be familiar to the reader from NMR (e.g. spin-spin
double resonance, COSY, SECSY etc.). Besides theory and
the technique a considerable amount of space is also given
(in an appendix) to the instrumentation needed to carry out
such experiments and to the analysis of data. Chapter 6, by
J. Allgeier et al., shows that pulsed ESR measurements are
also now being carried out at high fields; here the authors
describe their W-band spectrometer, which operates at a
microwave frequency of 95 GHz, about ten times higher
than that of a conventional X-band instrument (ca. 10 GHz).
244
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Verlagsgesellschajt mbH, W-6940 Wemheim, 1992
However, the evident advantages of this higher frequency
band as regards spectral resolution and sensitivity are
gained at the cost of more complex and expensive instrumentation.
A welcome feature of the book is that it also deals with
those modern CW-ESR techniques that are related to the
pulsed methods. Thus, in Chapter 7 K. McLauchlan reports
on methods for detecting transient free radicals using CWESR. After a very good introduction to the theory and the
experimental techniques the author discusses chemically induced dynamic electron spin polarization (CIDEP) and its
application to studies of rate processes in solution, illustrated by various examples. In Chapter 8 Ya. Lebedev, one of
the pioneers in the area of high-field ESR, describes CWESR techniques using microwave frequencies of 100 GHz
and above. In addition to the physical principles he discusses
technical aspects of all the high-field instruments of this kind
that exist up to now. A considerable amount of space is
devoted to chemical applications of such measurements, especially those that are inaccessible to ESR spectroscopy in
the conventional frequency bands. In view of the great importance of imaging techniques in NMR one could hardly
fail to include, in a book on modern ESR techniques, a
contribution on ESR imaging. This topic is covered in Chapter 9 by s. and G. Eaton, who give a good survey of the
current state of the art in this field. Here pulse techniques are
beginning to play an increasingly important role. Applications to radiation chemistry, to polymer chemistry, and in
the area of biological materials are described.
This book is intended for readers who wish to learn mainly
about methods, techniques, instrumentation, and the sometimes difficult problems of data analysis in both pulsed and
continuous-wave ESR. The reader must already have a solid
background knowledge of magnetic resonance and of the
analogous NMR techniques. Thus the book is addressed to
the specialist rather than the novice. A recent review article
by A. Schweiger[*]can be recommended as an introduction
to the field of pulsed ESR.
Most of the authors in the book use application examples
only to illustrate the techniques, and some of the chapters
contain too little of this kind of material for my taste. One
reason for this is that up to now very few applications-orientated research groups have adopted pulsed ESR methods,
and consequently only a few systems of relevance to chemistry have been studied. In future these methods will become
especially important in situations where they can yield information obtainable only with difficulty, if at all, by conventional ESR. Using pulsed ESR one can follow the timedependent development of species such as photoinduced free
radicals or triplet state molecules on time-scales from a few
nanoseconds to milliseconds, so as to give information about
the mechanisms of radical formation and conversion. For
paramagnetic species with lifetimes longer than a few microseconds one can also use pulsed ENDOR to obtain valuable information about the electron distribution (via the hyperfine couplings). Time-resolved ESR techniques also make
it possible to directly follow rate processes (by means of
relaxation time measurements), thereby providing an insight
into the motional processes of the molecules being studied.
Certain CW and pulsed methods yield complementary information, for example ENDOR and ESEEM. For readers
whose interests lie mainly in the biochemical and biological
applications of the techniques discussed here, the recently
published book Advanced EPR-Applications in Biology and
[*I
Angew. Chem. 1991, 103, 223-251; Angew. Chem. Int. Ed. Engl. 1991, 30,
265-292.
0S70-0833/92/0202-0244$3.50+ ,2510
Angew. Chem. Int. Ed. Engl. 31 (1992) No. 2
Biochemistry, edited by A. J. Hoff (Elsevier), can be recommended.
Pulsed ESR methods are now at the beginning of a development that could follow a course analogous to the enormous qualitative improvement of NMR techniques that has
occurred in recent years. However, it remains to be seen
whether microwave pulses will “exorcize the evil from
ESR”-as
has happened in the case of NMR-thereby
opening a new “Golden Age” for ESR spectroscopy. Everyone who wishes to get to grips with these new and fascinating
techniques, or who even foresees possible applications in his
or her own research, is strongly recommended to read this
book. Regrettably, however, the very high price-which has
now become the rule rather than the exception for books of
this sort--will limit the potential readership.
Wolfgang Lubitz
Max-Volmer-Institut fur Biophysikalische
und Physikalische Chemie
der Technischen Universitat Berlin (FRG)
One Dimensional and Two Dimensional NMR Spectra by
Modern Pulse Techniques. Edited by K . Nukunishi. University Science Books, Mill Valley (USA), 1990. XII, 234 pp.,
paperback $29.95. - ISBN 0-935702-63-6
Yet another book on NMR methods has been published;
in this the aim is to convey a knowledge of NMR by means
of a catalogue of 92 experiments, rather than by a systematic
form of presentation. In accordance with the book‘s title, the
examples are arranged in two groups consisting of 31 onedimensional (1 D) and 61 two-dimensional (2D) experiments. Each experiment is described in about half a page of
text with a few literature references (in which the name Bodenhausen has been wrongly spelled in nearly every case),
together with a diagram showing the pulse sequence and the
structural formula of the compound. The spectrum is reproduced on the opposite page, edited in a form which corresponds to the structural formula, so that the assignments are
directly apparent. A set of parameter values is also shown
alongside the spectrum in most cases, although unfortunately these are often too small to be read clearly and are insufficient to enable one to do further work on the problem;
moreover, the accompanying text seldom includes experimental details.
The selection of experiments covers nearly all the standard
types of problems nowadays encountered in organic chemistry. Thus the 1 D part includes examples of techniques such
as NOE difference measurements, SPT, DEPT, selective decoupling, and suppression of water signals, while in the 2 D
part one finds, in addition to the expected variants of COSY
and NOESY, examples of HOHAHA, ROESY, and 2DINADEQUATE experiments.
There are a few key molecules, such as p-ionone or strychnine, that are used again and again as examples in the book,
thus enabling the reader to progress comfortably from simple types of spectra to more complicated types as applied to
the same molecule; this is undoubtedly one of the book’s
main strengths. On the other hand the examples chosen are
sometimes unnecessarily complicated, as in the cases of
brevetoxin (No. 56), cyanoviridin (No. 84), or dictyotalide
(No. Sl), which tend to obscure the merits of the techniques
under discussion rather than to clarify them. Nevertheless,
the book as a whole offers a wealth of stimulating ideas
taken from all the main research themes of organic chemistry, thus conveying to the reader some of the pleasure
Angew. Chem. Inf. Ed. Engl. 31 (1992) No. 2
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evoked by the power of modern NMR spectroscopy. The
spectra that are reproduced, which are certainly the main
substance of the book, are of better than average quality.
However, there are a few criticisms that must be mentioned.
For example: the convention of having the f , axis as the
horizontal one is not applied consistently; for inversely
recorded spectra (such as some of the examples of HMBC
and HMQC experiments), the fiprojection appears sometimes at the left-hand and sometimes at the right-hand border of the spectrum; too often some of the peaks of the
projection are allowed to protrude into the 2 D spectrum,
which to me appears rather inelegant. Here it becomes evident that the book is not a unified whole but a collection of
contributions from a number of spectroscopists using different spectrometers with different software.
There is a 40-page appendix entitled “Principles of FTNMR’, in which an attempt is made to explain the theory
behind the experiments that are included. Everyone is likely
to appreciate that a meaningful summary of the theory of
modern 1 D and 2 D multipulse NMR spectroscopy is not
possible within such a limited space, and consequently the
reader is unlikely to derive anything useful from this account.
In summary it can be said that this book offers, at a reasonable price, a stimulating survey of the NMR methods
nowadays used in organic chemistry. It can certainly be recommended for libraries and textbook collections, and for
serious organic chemists who wish to learn what their NMR
section should be capable of; it is less suitable for NMR
specialists, who need a more detailed knowledge of the subject than can be conveyed within the space of this book.
Stefun Berger
Fachbereich Chemie
der Universitat Marburg (FRG)
Modern Methods in Protein- and Nucleic Acid Research.
Edited by H . Tschesche. de Gruyter, Berlin, 1990. ix,
446 pp., hardcover DM 330.00.-ISBN 3-1 1-012275-8
This book can be regarded as a continuation of the series
“Modern Methods in Protein Chemistry”, previous volumes
ofwhich appeared in 1983, 1985, and 1988. The latest developments in analytical and preparative methods are here described in 20 review articles by well-known authors belonging mostly to German research groups. This volume is the
first to cover molecular biological methods. After a brief
introduction to the techniques, the methods are described in
turn using examples from each author’s own field of research, sometimes including an experimental section giving
practical details. Each article provides an up-to-date list of
references, including review articles and monographs. The
book is convenient to use and sturdily bound. However, the
authors’ typescripts have been directly reproduced, and the
resulting lack of uniformity in type style and line spacing is
rather distracting.
The first three articles are devoted to nucleic acids chemistry and molecular biology. H. Tschesche et al. describe the
use of digoxigenin-I 1-dUTP as a realistic alternative to radioactive labeling. w. Kramer and H.-J. Fritz discuss the
advantages and disadvantages of the various methods for
preparing mutants using oligonucleotide techniques. B. S.
Reckmann then describes new analytical procedures in DNA
diagnostics. H. Wagner and J. Heinrich kindle interest in free
flow electrophoresis, an elegant preparative electrophoretic
method for purifying peptides, proteins, and whole cells. Other innovations in the purification and isolation of proteins
Verlagsgesellschaj? mbH, W-6940 Weinheim, 1992
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