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Book Review Biotransformations in Organic Chemistry. By K. Faber

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cluding the relevant methods of measurement and their evaluation. Volume 1 ends with a further chapter on the design
of extractors, and on choosing a design and layout using
data from pilot experiments.
Volume 2 begins with four chapters on the application of
liquid-liquid extraction methods in some special areas.
Chapter 1 describes the use of reactive extraction techniques
in metal refining. The basic principles and special extra conditions that apply to this field of application are first explained, then the processes currently used for individual
metals o r groups of metals are described. Chapter 2 is concerned with the reprocessing of nuclear fuel elements, beginning with a general introduction and a description of the
different types of equipment, then going on to describe the
processes currently used and possible future developments.
However, it is questionable whether the details of the associated control technology and safety measures included at the
end of this chapter are relevant to the main theme of the
book. The following two chapters deal with applications of
extraction technology in the pharmaceutical and food industries. with details of some special processes used, such as
high-pressure extraction and the use of two-phase aqueous
systems. The final chapter summarizes the various areas of
application and indicates the directions in which these are
now developing.
The work does not claim to be an introduction to the
subject; instead the contributions by recognized experts are
intended to summarize the current state of knowledge and to
indicate topics for further research. The material is presented
from a scientifically orientated standpoint, and is thus likely
to be mainly of interest to engineers and chemists in universities and industrial research laboratories. The volumes give
a good overview of the fundamental theory and some important areas of application of extraction processes. The comprehensive subject index makes it easy to locate information
on special topics. There is some overlapping of subject matter between the individual contributions, but one can hardly
expect that to be completely eliminated in a work of this
kind. The fundamental theory is covered thoroughly and
forms the basis for a treatment that emphasizes recent developments, including some unconventional ones, and this is
therefore a valuable addition to the literature on liquid-liquid extraction.
Eherhard Aufilerheide
Degussa
Antwerp (Belgium)
Selective Biocatalysis. A Synthetic Approach. By L. Poppe
and L. Novuk. VCH Verlagsgesellschaft, Weinheim, 1992.
XII, 319 pp., hardcover DM 168.00.--ISBN 3-52728372-2
Biotransformations in Organic Chemistry. By K . F u h .
Springer, Berlin, 1992. IX, 319 pp., hardcover
DM 128.00.--ISBN 3-540-55762-8
Methods based on enzyme catalysis have become firmly
established in the standard repertoire of asymmetric synthesis techniques because of their high selectivities--in some
instances serving to complement, in others to compete with,
the conventional chemical methods of organic synthesis- -as
is documented by the almost exponential growth of the literature on new applications of enzymes for the preparation of
chiral intermediates. Both methods based on fermentation
and, more especially, the use of isolated enzymes, are benefiting from the continuing growth in the numbers of known
enzyme types (now over 2500) and of those that are commer-
cially available (over 350). The task of collecting together the
huge wealth of reactions that can be performed, critically
reviewing the possibilities, and presenting this information
clearly in book form as a guide for synthetic chemists interested in applying these methods is a difficult one from several
viewpoints. Firstly. this area of research is undergoing rapid
development, and consequently by the time the book is
printed the contents will no longer be completely up-to-date.
Secondly, the resulting publication is in competition with a
steadily growing number of review articles in the relevant
specialist journals, which are usually read by synthetic
chemists and can cover matters of detail from a more expert
standpoint. The authors of the two monographs reviewed
here have taken up this challenge, and have almost simultaneously produced works that cover the same topics and have
also turned o u t to be very similar in content. Thus it is
appropriate to compare them.
In both volumes a general introduction to the methods is
followed by the main part i n which enzyme-catalyzed (and
also some selected yeast-mediated) transformations are
treated in a hierarchical sequence. Some noticeable differences between the two treatments will be mentioned here. In
the book by Poppe and Novik the discussion of some process-related problem areas (the characteristics, classification,
kinetics, and immobilization of enzymes; the reaction medium; microbial transformations; the modification of biocatalysts; catalytic antibodies) is preceded by a detailed chapter
of 40 pages on stereochemistry, in which the nomenclature,
basic principles, and especially the classification of the different possible types of selectivity (diastereomeric,
diastereotopic, enantiomeric, and enantiotopic) are defined.
The latter system, although somewhat unconventional,
serves as a very useful means of classifying the asymmetric
reactions discussed in the main part of the book. However,
the rigid arrangement according to types of biocatalysts
means that specific chemical themes are scattered throughout widely separated chapters (e.g., hydrolysis by enzymes is
treated in Chapter 3, by baker’s yeast in Section 5.4, and by
other microorganisms in Section 6.2.1). In contrast Faber,
after a short introduction (probably based on a lecture
manuscript), plunges straight into the main business and
follows the general arrangement used in a successful earlier
work with a similar title and subject (H. G . Davies, R. H.
Green, D. R. Kelly, and S. M. Roberts, Bioirrmsfi,r~ra!ions
in Prepnrarive Organic Chemistry, Academic Press, London,
1989). In a less helpful arrangement, however, he treats the
reversal of hydrolytic reactions in a separate chapter on
”Special Techniques”, in which the action of enzymes in
organic solvents leading to the formation of esters, lactones,
and amides is described. In both books the grouping together of basic principles and general features of the methods
should help to prevent the contents from losing their usefulness too quickly as the more detailed material becomes outdated.
The main parts of both books provide the reader with
what is promised by the title, namely a wealth of information
with examples of reactions sensibly chosen from the synthetic organic chemist’s viewpoint, i.e. with due regard to preparative usefulness (high chemical and optical yields). Both
books place emphasis on hydrolytic and reductive transformations with their respective reverse reactions, which are at
present the reaction types of greatest practical importance.
The authors have made liberal use of figures and tables to
present the material in a way that is textually and visually
clear. Both monographs concentrate on “main-stream”
preparative applications, and consequently some aspects of
enzyme-catalyzed reactions are not treated as thoroughly as
one might wish (in particular Poppe and Novkk devote a
mere 11 pages to “Other Enzymes and Microorganisms”,
thus barely scratching the surface of this topic). However,
the surveys are well written (apart from the minor faults
mentioned below) and each chapter includes a comprehensive and up-to-date bibliography (‘‘Poppe and Novak” contains 1660 citations altogether and “Faber” 1456, extending
up to about mid-I991 in both cases), with references to the
most important original papers and recent review articles.
Scientists who keep up with the current literature will find
few surprises here (though occasionally they may be surprised to find which publications are not cited), but they will
appreciate the clearly presented comparisons. For others
these books offer a rapid and detailed survey of the main
areas of activity and new methodological developments in
this highly topical and expanding field of research. Of the
two books, “Poppe and Novak” is more in the nature of
a scientific review, with a hierarchical arrangement of
contents according to selectivity types which is best suited
to the needs of the researcher. “Faber”, on the other hand,
has a more general approach based on types of transformations, with some of the character of a textbook, and
didactic qualities that make some parts of it really enjoyable
to read.
“Poppe and Novak” has been carefully edited, and only a
few small isolated and unimportant errors are evident in the
formula schemes (e.g., in Fig. 4.6. a the oxidizing and reducing agents have been interchanged) and in the Latin names
of the microbe species (e.g., “Penicillinum camamberti” instead of Penicilliurn camembrrtii). That Fdber has not been
afraid to tackle the hard work of desktop publishing only
becomes apparent on close examination of the book (actually on the imprint page), which accounts for the lower price.
However, the risk involved in this has exacted a penalty, as
careful reading unfortunately reveals a higher incidence of
errors in formula diagrams (e.g., an extra OH group in
Scheme 2.160, and a vinyl instead of an ally1 substituent in
Scheme 2.164), in the numbering of references, and in captions (e.g., Table 2.8), despite the fact that the author acknowledges the help of an internationally respected colleague in checking the work. In particular Chapter 2.1.4,
“Hydrolysis and Formation of Phosphate Esters”, contains
many errors that need to be corrected, including inaccurate
formulations (e.g., glucose-6-phosphate as an essential cosubstrate of dehydrogenases) and many incorrect statements
(e.g., that carbohydrate triphosphates are involved in glycosyl transfer reactions, that phosphatases are employed for the
synthesis of phosphate esters, that kinases are a subgroup of
phosphatases-could this misunderstanding be the reason
for the inclusion of enzymic phosphorylations in Chapter 2.1
on “Hydrolytic Reactions”?-that nucleoside triphosphates
are intrinsically stable in solution, and so on). Also the index
(only 7 pages) is less than perfect with regard to completeness
and conciseness of the entries.
Although Faber’s book is more attractively priced and,
for this reason especially, might help to fill a gap in the
training of organic chemistry students, I have slight reservations about recommending it as a textbook to accompany a
special lecture course. As a reference work for the desks of
chemists engaged in research in this field “Poppe and Novak” seems more suitable, although the higher price may be
an obstacle to individuals buying it. As the subject matter
covered by each book alone is (rather surprisingly) considerably less than the sum of the two, chemical libraries should
not hesitate to buy both.
Wolf-Dieter Fessner
Institut fur Organische Chemie und Biochemie
der Universitat Freiburg (FRG)
New Books
see next page
A n g w . Cliem. I n t . Ed. EngI. 1993, 32, Nu. 6
0 VCH
Verlugsgesellrchufi mhH, W-6940 Weinheim,1993
0570-0833/93/0606-0921 $ 10.00f ,2510
921
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