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Book Review Wood and Cellulosic Chemistry. Edited by D. N. S. Hon and N. Shiraishi

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atomic to the molecular level, the parity-violating weak neutral current perturbation lifts the degeneracy of space-inverted enantiomers. The energy difference is only approximately
lo-’’ kJmol-’, and corresponds to an excess of just one
molecule of D- or L-alanine in a racemic mixture of loi7
alanine molecules in thermodynamic equilibrium at terrestial temperatures. Ab initio calculations indicate that the
predominant isomer has the L configuration. Janoschek argues that this minuscule bias, appropriately amplified, is
responsible for the fact that all metabolically functional biopolymers are monochiral, both at the monomer level (L-aamino acids, D-sugars) and in the helical polymer conformations (right-handed polypeptide a-helix, B-DNA), i.e., that
the monochirality of the molecules of life has its origins in
the systematic chiral bias of the elementary particles. Various
amplification mechanisms are described in support of this
thesis. However, the reader is cautioned that “any hypothesis on long term processes such as homochirality evolution
will most probably remain experimentally unproven for
ever.”!
After a brief discussion of Kauzmann’s “principle of pairwise interactions”, Derflinger gets to the heart of his subject:
a vigorous critique of the theory of chirality functions developed by Ruch and Schonhofer that focuses on the concept of
“qualitative completeness”. He thus revives a controversy
that had erupted briefly in the pages of Theoretica Chimica
Acta in 1978. Because only one side of the story is told in this
chapter, the reader needs to be made aware of two rebuttals,
neither of them cited here, by Ruch (Theor. Chim. Acta 1978,
49,107) and by Mead (Theor. Chim. Acta 1980,54,165).The
discussion of two other controversial concepts, “qualitative
supercompleteness” and “hyperchirality”, is equally partisan in tone. The chapter concludes with a description of a
method for enumerating enantiomeric pairs.
Snatzke reports on various methods that are employed to
specify the sense of helicity in molecules, points out ambiguities (a short path of a three-dimensional curve can be approximated by either a right- or a left-handed helix), and
discusses rules designed to correlate the absolute structures
(configurations) of chiral chromophores with the signs of
appropriately chosen circular dichroism bands. Surprisingly,
there is no reference to the excellent review on helical molecules in organic chemistry by Meurer and Vogtle (Fortschr.
Chem. Forsch. 1985, 127, 1). The theme of absolute configuration is also featured in a chapter by Kratky, in which
anomalous dispersion of X-rays is described as the method,
pioneered by Bijvoet, used to determine the sense of chirality
of molecules in crystals with respect to a macroscopic (absolute) reference frame.
The need for enantiomeric purity is particularly acute in
pharmacology and medicinal chemistry. This explains why
four of the ten essays in this collection are devoted to strategies for the production of enantiomerically enriched (and, in
the limit, enantiopure) compounds. Faber and Griengl describe the use of enzymes as efficient, cheap, and highly
enantioselective biocatalysts in the preparation of optically
active alcohols, amines, and acids (e.g., enzymatically catalyzed asymmetric reductions of ketones and hydrolyses of
meso diesters). Winterfeldt distinguishes, and illustrates with
examples, three general methods for achieving enantiomeric
purity : by resolution of racemates, by reactions whose
educts are enantiopure natural products, and by enantioselective reactions or asymmetric syntheses. Brunner discusses
the use of chiral transition metal complexes as catalysts in
asymmetric syntheses (e.g., hydrogenation of olefins with Rh
complexes of Diop). Strategies for the separation of enantiomers by liquid column chromatography are the subject of
Angew. Chem. I n [ . Ed. E n d . 31 (19921 N o . 6
a chapter by Lindner. The nature of chiral recognition between the mobile and stationary phases determines resolution efficiency; column packings are classified, and compared, according to type : derivatives of biopolymers (e.g.,
microcrystalline triacetylcellulose), chiral synthetic polymers
(e.g., Okamoto’s helical poly(trity1 methacrylate)), and chiral monomers (e.g., cyclodextrin derivatives).
Although it would be asking too much to expect complete
coverage of all aspects of this subject, given its enormous
scope, it was nevertheless disappointing to find no mention
of topological chirality (the chirality of trefoil knots, catenanes composed of orientated rings, Mobius ladders, and so
forth) in synthetic and naturally occuring molecules. I was
not able to make much sense of the essay by S. Hoffmann,
which I found to be intellectually impenetrable. Most texts of
this nature are plagued by errors, and the present volume is
no exception (e.g., on p. 171 the “symmetry elements” of
ethylene are given as ‘‘30, 3C,, and i“).Despite such shortcomings, however, this volume deserves to be read by anyone interested in this important topic.
Kurt Mislow
Department of Chemistry
Princeton University, Princeton NJ (USA)
Wood and Cellulosic Chemistry. Edited by D. N . S. Hon and
N . Shiraishi. Marcel Dekker, New York, 1991. VIII,
1020 pp., hardcover $234.00.-ISBN 0-8247-8304-03
Wood is one of the most important renewable raw materials and energy media. The growth of wood in forests makes
a significant contribution to reducing the amount of carbon
dioxide in the atmosphere. The carbon dioxide produced
from fossil and living carbon sources by burning and respiration can, over long periods, be transformed back into organic compounds. For this reason alone, it is clear that wood
chemistry and the use of wood as a chemical raw material is
currently of great importance.
Research in wood chemistry now involves many different
fields of science, and the published results are often widely
scattered; surveys that aim to bring together this knowledge
in an ordered way are therefore very useful. The book reviewed here is largely successful in achieving that objective.
The authors, 18 Japanese and four American scientists,
are all recognized experts in their fields. The book is divided
into three main sections, containing 21 chapters altogether.
Part 1, “Structure and Chemistry”, starts from the structure
and mode of formation (lignification) of the woody tissue of
the cell wall in plants, and goes on to describe in turn the
chemical properties of each of the wood constituents that are
bound together in the natural polymer structure-cellulose,
hemicellulose, lignin, and substances present in the wood.
Separate chapters are devoted to the chemistry of the bark,
and to the chemical characterization of wood and its constituents. This part could have been even further improved
by devoting a separate chapter to the biochemistry of wood
formation.
In Part 2, “Degradation”, some of the chapters deal with
topics that have not previously been treated in monograph
form, such as coloration and discoloration, and the photochemistry of wood. The degradation of wood by chemical,
microbiological, enzymic, and pyrolytic mechanisms is described in a detailed and highly informative way. However,
it is disappointing that this part does not also deal with the
gasification and liquefaction of wood.
(0VCH Verlagsgese/lsrha/fmbH, W-6940 Weinheim, 1992
0570-0S33!92!0606-0801 $3S0+.2Sj0
801
Part 3, “Modification and Utilization”, discusses the
chemical basis for modifying the properties of wood and
cellulose so as to broaden their areas of use, both as constructional materials and as chemical raw materials. The
main areas considered are the chemical modification of
wood and cellulose, the plastification of wood, wood-polymer composites, and adhesives for wood. There is also a
chapter (unfortunately rather too brief) on the use of wood
and cellulose as sources of chemicals and energy.
Considered as a whole, the work offers a very good, up-todate, and in some parts detailed survey of the specialized
subject of wood and cellulose chemistry. The large number
of authors has resulted in some unavoidable overlapping. A
particularly useful feature is the large number of literature
references given at the end of each chapter; there is, however,
a very marked preponderance of Japanese publications. The
book can be recommended for everyone in research and
teaching who seeks an up-to-date account of the present
state of knowledge regarding the chemistry of renewable raw
materials, natural polymers, wood, and cellulose.
Otto Wienhaus
Institut fur Pflanzenchemie und Holzchemie
der Technischen Universitat Dresden
Abteilung Forstwirtschaft, Tharandt (FRG)
Vitamin C: Its Chemistry and Biochemistry. By M . B. Davies,
J. Austin, and D. A . Partridge. Royal Society of Chemistry,
Cambridge, 1991. 154 pp., paperback E 13.50. ISBN 085186-333-7
An up-to-date and compact treatise on various aspects of
ascorbic acid, this important vitamin, is most welcome, particularly in view of the discrepancy between the biological
importance and the limited amount of sound knowledge
available, and because of widespread interest on the part of
the general public and in the marketplace. The back cover
announces this book as just that: the “first” to provide an
in-depth, interdisciplinary study of this essential and fascinating compound.
Well, the reader gets only some of this: there is a nice and
coherent presentation of the history of scurvy and of the discovery of vitamin c , with due emphasis on Szent-Gyorgy
and on Haworth, with related stories providing good reading
(Chapters 2 and 3). Chapter 4 describes the synthesis and
manufacture, which, with a yearly output of more than 40000
tonnes, is certainly of quantitative interest. In this chapter
one already begins to wonder about the overall scheme of the
book, since at the end there is a lengthy section on further
chemical reactions that ascorbate can enter into, but without
offering a clue as to why this would be of interest.
Chapter 5 is on the biochemistry, and the bottom line is
that many actions are being discussed here and there, but
there is still much confusion. This is well illustrated by the
detailed description of some metabolic pathways, such as the
mitochondria1 respiratory chain, in lengthy sequences of reactions but only few, if any, clear statements of how ascorbate is chemically involved. AFR, presumably an abbreviation for the ascorbate free radical, is included but not really
explained. The few words about the interactions between
tocopherol and ascorbate do not reflect current knowledge
in this area. Similar comments apply to Chapter 6, on medical aspects: while generally satisfactory, the presentation
sometimes doesn’t quite make it to the point; I had trouble,
for example, trying to understand the passage on page 99 on
“vegetarians being in rude health, ascorbutically speak802
0 VCH Verlagsgesellschrfi mbH, W-6940
Weinhrim,1992
ing”(?). The author of this part of the book may not have
been from the medical profession, judging from the way
some diseases were described. Chapter 7, on inorganic and
analytical aspects, was more within the field of expertise, but
here the inclusion of four pages on vitamin B,, in atomic
detail left the reader perplexed, because the connection to the
topic, namely vitamin C, was not made clear.
In summary, the book of about 15Opages is attractive
initially, but, as even the authors say, the field is still mysterious in several ways. The bibliography could have included
some of the more recent literature, e.g. the book for the
layman by Linus Pauling (“How to Live Longer and Feel
Better”), and the “Handbook of Vitamins” by Machlin. Also, one might disagree that the latest conference of the New
York Academy of Sciences on Vitamin C was a “Third
World Conference”.
Helmut Sies
Institut fur Physiologische Chemie
der Universitat Dusseldorf (FRG)
Ion Exchangers. Edited by K. Dorfner. de Gruyter, Berlin,
1991. XXXI, 1495 pp., hardcover DM 680.00.-ISBN 311-010341-9
A whole generation of chemists received their first initiation into the subject of ion exchangers from Dorfner’s slim
volume entitled “Ionenaustauscher”. A much weightier
book, “Ion Exchangers”, has now appeared. In this a team
of authors under Dorfner’s guidance has covered all the
most important aspects of ion exchangers in a single volume
of about 1500 pages.
An introduction to the basic principles of ion exchange is
followed by several contributions dealing comprehensively
with the synthesis of ion exchangers. Here it is pleasing to
note that due importance has been given to synthetic organic
ion exchange resins, the most commercially important group
of materials. All the important areas of industrial application are competently described by experts; these range from
conventional water treatment processes to the applications
of ion exchangers and polymeric adsorbers in biotechnology.
The contribution by Sherrington on the influence of the
structure of the polymer on the reactivities of the functional
groups is especially worth reading, despite being relegated to
an inconspicuous position in the last part of the book. Also
there is a short but highly informative section which surveys
the literature on ion exchangers in general, and describes the
use of computer-based information retrieval methods. All
the contributions include many references to original papers.
There is an appendix containing an index of commercially
available ion exchangers, and the book is completed by a
useful subject index.
Published work up to the mid-eighties is covered in considerable detail, but later results have only rarely been included.
The editor has been remarkably successful in avoiding overlapping of subject matter; where this has been allowed to
occur, it makes it much easier to read a particular article
without needing to know the contents of the previous one.
There is a certain amount of inconsistency in the nomenclature and units, but it could not have been avoided, and this
reviewer did not find it troublesome. The print is clear and
legible, and the tables, formulas, figures, and flow diagrams
are mainly clear and informative.
However, the frequent careless errors are a nuisance, of
which the following are two examples. In the tables on
pages 96 and 1297, which are largely identical in content, we
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Angew. Chem. I n t . Ed. Engl. 31 (1992) No. 6
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