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Book Review Methods in Stereochemical Analysis I. Stereochemical Applications of NMR Studies in Rigid Bicyclic Systems. By A. P. Marchand

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sions presented by these authors can possibly stand up to
critical scrutiny of the evidence. Presumably, the lecture itself provoked some lively discussion, and it seems perhaps
a pity that only one side of the story is presented in the
printed proceedings.
Several chapters mention the theorem due to Hohenberg
and Kohn, according to which all ground-state properties
of any system, including the wave function, are functionals
of the charge density distribution, i.e. they can be calculated in principle from a knowledge of the charge density.
The “in principle” is important, because nobody so far
seems to actually know how to calculate these functionals.
However, since the charge density is an observable while
the wave function is not, the Hohenberg-Kohn theorem
and its repercussions (discussed in the chapter by Parr)
may help to explain why interest among experimentalists
and theoreticians in charge-density studies of molecules
and extended systems is so lively. The publication of this
book is an expression of this interest. From it, the reader
can hope to find some of the questions that are being
asked in the area as well as some of the answers that are
being given.
Jack D . Dunitz [NB 603 IE]
Institut fur Organische
Chemie der ETH, Zurich
Covalent Catalysis by Enzymes. By L. B. Spector. SpringerVerlag, Berlin 1982, xii, 276 pp., bound, DM 78.00
Covalent enzymic catalysis (double displacement) has
been known for a long time. It is accepted as a guiding
principle, almost without exception, in the mode of action
of vitamins as enzyme cofactors, that the chemical process
of substrate reaction takes place on the vitamin unit. Some
of these cofactors are covalently bound to their apoenzyme ; knowledge of covalent enzymic catalysis stretches
back more than half a century.
In 1971 R . M . Bell and D . E . Koshland compiled a list of
60 enzymes where the application of critical criteria revealed a high likelihood of covalent catalysis. A little later
this figure was raised to 140 by L. B. Spector, and the much
more thorough-going claim was made that all enzyme catalysis proceeds oia covalent enzyme-substrate intermediates.
The present monograph is an attempt to strengthen this
concept.
It would have been a good idea to acquaint the reader
with the criteria for direct reaction between substrates (single displacement; kinetic sequential; stereochemical inversion of configuration) together with their alternatives (double displacement; kinetic ping-pong; stereochemical retention of configuration; exchange reactions in the absence of
the second substrate; isolation of an enzyme substrate
complex and demonstration of its kinetic competence).
There is only inconclusive kinetic evidence for single displacement without discernible stereochemical consequence. The author founds his assertion that all catalysis is
covalent thus : “Single displacement is purely speculative,
because no positive evidence in support of it exists. For the
documentation of this statement I can do no more than
refer the reader to the whole corpus of chemical literature
on the chemical mechanism of enzyme action.”
The experimenter is faced with a difficult problem in demonstrating direct interaction between the substrates; he
must exclude covalent catalysis by every possible test, of
Angew. Chem. Int. Ed. Engl. 23 (1984) No. 1
necessity this means negative results, thus completing a vicious circle. This, however, does not mean that single displacement reactions do not exist as this author so vehemently insists. Inversions of configuration which indicate
direct reaction of the substrates are craftily interpreted by
the author as triple displacements. This may be the case
but it has not been demonstrated. What is certain is that
the examples cited (acetate kinase, adenosine-phosphoribosyl transferase) are insufficient to lead to a conclusion.
It would have been a good idea to acquaint the reader
with examples that mimic covalent catalysis : exchange
reactions with a substrate may result from a second substrate being firmly attached to the enzyme; a substrate
alone may become covalently attached to the enzyme in a
side reaction; unphysiological substrate analogues (e. g.
suicide inhibitors) may form covalent enzyme substrate
bonds when the physiological substrate does not. Finally,
some isotope labeling experiments that purport to demonstrate covalent attachment can be attributed to faulty control experiments.
Conclusions that catalysis is covalent are only convincing when all the criteria are fulfilled or when a deviation
can be explained. It lies in the nature of a claim that all catalysis is covalent, that the author ignores this critical illumination and does not adequately distinguish experimental demonstration from experimental indications. It can be
left to the reader to check the significance of the results described and to decide whether he is reading “covalent catalysis above all” or “above all covalent catalysis”.
In this spirit it is possible to recommend this book,
which is deliberately provocative, lively and, on occasions,
informative, to everyone with an interest in the mechanism
of enzymic reactions.
Hermann Eggerer [NB 600 IE]
Physiologisch-ChemischesInstitut
der Technischen Universitat Munchen (FRG)
Methods in Stereochemical Analysis I. Stereochemical Applications of NMR Studies in Rigid Bicyclic Systems. By
A . P. Marchand, Verlag Chemie International, Deerfield
Beach 1982, 231 pp., bound, DM 280.00
This book is the first of a new series of monographs to
be edited by the author, which is to cover the application
of NMR, together with other spectroscopic and physical
methods, to stereochemical problems.
This first volume is devoted to the NMR spectroscopy of
the bicyclo[2.2.1]heptanes and the [2.2.2]octanes, which
have achieved great importance, not only as models for
spectroscopic investigation but also for preparative and
mechanistic studies, since these rigid molecules are particularly suitable for stereochemical studies.
The book is divided into three chapters. The first chapter presents methods of signal assignment and discusses
them in detail using examples. The chapter begins with a
study of the application of lanthanoid shift reagents in the
evaluatibn of ‘H-NMR spectra, where the theoretical
background is largely ignored; then the homo- and heteronuclear nuclear Overhauser effect (NOE) is introduced. A
word of criticism is pertinent at this point. Even though
this monograph does not aim to discuss measuring techniques, the enormous refinement of NMR techniques in
recent years makes it desirable to discuss assignment aids
somewhat more fully. This is particularly the case since it
87
cannot be the aim of this book only to review the methods
that have been described for bicyclic systems, but should
also stimulate further investigations applying the most
modern of possibilities.
The second chapter covers stereochemical applications
of chemical shifts in several nuclei (’H, I3C, I9F and 31P);
first steric effects then electronic substitution effects are
discussed in terms of their dependence on the stereochemistry of the molecule. The tabular presentation of some of
the conclusions from investigations on various types of
compounds is particularly clear. The correlation of chemical shifts with charge density for a large number of bicyclic
carbonium ions is discussed at the end of this chapter; the
results are again collected in tabular form.
The third chapter, which makes up by far the largest
portion of the book, deals with the measurement and interpretation of spin-spin couplings. A short, general introduction is followed successively by discussions of homo- and
heteronuclear coupling over, one, two, three, four and
more bonds, with a plentiful supply of data listed to illustrate each case.
There is no doubt that this book fills a vacant niche in
the review literature and will provide any chemist who is in
some way concerned with compounds of this class with a
wealth of valuable information. It should be included in
any balanced NMR library. However, it i s to be feared
that, in the present financial climate, the unusually high
price will prevent the wide dissemination that the book deserves.
Helmut Duddeck [NB 602 IE]
Abteilung fur Chemie der
Ruhr-Universitat Bochum (FRG)
NATO AS1 Series. Series B: Physics, Vol. 92: The Physics
of Superionic Conductors and Electrode Materials.
Edited by J. W . Perrum. Plenum Press, New York 1983.
viii, 281 pp., bound, $ 45.00.--ISBN 0-306-41271-3
International Series of Monographs on Chemistry. Biosynthesis of Indole Alkaloids. By Atta-ur-Rahman and A .
Basha. Clarendon Press, Oxford 1983. 270 pp., bound, $
49.00.--ISBN 0-19-855619-1
Chimica. Ein Wissensspeicher. Band 11. Allgemeine und
physikalische Chemie, technische Chemie. By H . Keune.
Verlag Chemie, Weinheim 1983. 520 pp., stitched, DM
45.00.-ISBN 3-527-25972-4
Advances in Chemical Physics. Edited by I . Prigogine and
S . R . Rice. Wiley Interscience, Chichester 1983. Vol.
LIII: 402 pp., bound, L 52.25.-ISBN 0-471-89569-5;
Vol. LIV: ix, 485 pp., geb. 6: 71.25.-ISBN 0-471-895709
Effects of Accumulation of Air Pollutants in Forest Ecosystems. Proceeding of a Workshop held at Gottingen, May
16-18, 1982. Edited by B . Ulrich and J . Pankrath. D.
Reidel Publishing Company, Dordrecht 1983. xviii, 389
pp., bound, HFI. 135.00.-1SBN 90-277-1476-2
The Chemistry of Functional Groups. Supplement D: The
Chemistry of Halides, Pseudo-Halides and Azides. Part 1
and 2. Edited by S. Patai and 2. Rappoport. Wiley Interscience, Chichester 1983. Part 1: xiv, 931 pp., bound./
Part 2: xiv, pp. 933--1867.-L 280.00.-ISBN 0-47110089-7
Topics in Stereochemistry. Vol. 14. Von N . L. Allinger, E. L.
Eliel, S . H . Wilen. Wiley Interscience, Chichester 1983.
ix, 315 pp., bound, L 90.25.--ISBN 0-471-89858-9
Riickstande und Vereunreinigungen in alkoholfreien Getranken. Mitteilung XI der Kommission zur Priifung von
Riickstanden in Lebensmitteln. A publication of the
Deutsche Forschungsgemeinschaft. Verlag Chemie,
Weinheim 1983. 60 pp., stitched, DM 20.00.-ISBN 3527-27325-5
Isotopeneffekte bei chemischen Reaktionen. By A . V. Willi.
Thieme, Stuttgart 1983. x, 182 pp., bound, DM 80.00.ISBN 3-13-592801-2
Progress in Physical Organic Chemistry. Vol. 14. Edited by
R . W. Taft. John Wiley, Chichester 1983, 374 pp.,
bound, 6: 66.50.--ISBN 0-471-06523-7
Ion Exchange Membranes. Edited by D. S. Flett. Ellis Horwood Publishers, Chichester 1983. 210 pp., bound, 6:
19.50.4SBN 0-853126402
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Angew. Chem. Int. Ed. Engl. 23 (1984) No. 1
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