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Book Review Die Technik der organischen Trennungsanalyse. Eine Einfhrung. By H. Laatsch

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Section 2 on biophysical and biochemical studies is the
longest in the book, with eight articles. The interaction with
DNA, which is important in relation to the effectiveness of
the compounds, is treated first, in articles dealing with quantitative aspects (E. Stutter et al.), X-ray diffraction studies
(G. Ughetto), computer modeling (.
R.IBrown and S. Neidle), and sequence selectivity (B. Pullman). However, there is
still no consensus among experts on the basic mechanism of
action, as is shown by the general articles on anthracyclines
by C. E. Myers et al. and on anthracenediones by K. Reszka.
Thus, in addition to the interaction with DNA, there are
discussions of the effects on DNA-topoisomerase I1 ( M . Potmesil) and on lipid oxidation and prostaglandin formation
(R. E Novak et al.).
However, it is in clinical application that biochemical
models undergo their ultimate test. This aspect, together
with pharmacology and toxicity, is treated in Section 3. The
introductory article by M . Grandi et al. on screening methods, which is fairly basic in content, is followed by newer
aspects of anthracycline resistance ( D . H. Kessel), of the
pharmacology of Menogaril, which has been developed from
nogalamycin (J. P. McGovern et al.), and that of anthracenedione ( M . D. Green et al.), together with tumor cell differentiation by anthracyclines ( A . M . Casazza). The short closing
contribution by the editor again emphasizes the fact that,
despite the wealth of experimental results, a firm understanding of antitumor activity is still a long way off. However, he urges continued research “... in order to understand
the mode of action of these valuable agents and to improve
their performance”.
This volume is extremely useful for everyone working on
synthetic, pharmacological or clinical aspects of anthracyclines or on antitumor therapy in general. Nowadays it is
hardly possible for an individual to read every original paper
which has an interdisciplinary connection with this topic.
This collective volume makes it easier to see beyond the
confines of one’s own special field. Thus, it enables the synthetic chemist and the natural products chemist, for example, to learn which compounds have progressed from
promising animal trials to clinical trials or use. However,
sentences such as “Aclacinomycine A is therefore essentially
ineffective in the major solid tumors” (p. 672), or “The side
effects were in general similar to those seen with doxorubicin” have a sobering effect.
As in the parallel series “Studies in Natural Products
Chemistry”, also published by Elsevier, the authors’ contributions are reproduced in “camera ready” form. Consequently the visual appearance is that of a wide variation in
type styles and in the presentation of formulas. The incidence
of typographical errors varies considerably from author to
author, and in this respect the standard falls far short of that
usually found in books that are typeset. These superficial
shortcomings would, of course, be acceptable if they were
offset by the contributions being more up-to-date and by an
advantage in price. Unfortunately, however, in most of the
articles the references extend only up to the end of 1986, or
occasionally to the beginning of 1987. Even with this method
of production it appears that at least a year has elapsed
between the submission of the manuscripts and the publication of the book, a delay which this reviewer has also experienced as an author in the parallel series. The subject index
consists of 8 1/2 pages. There is no index of cited authors; in
the computer age it should have been easily possible to
provide such an index, which would have been very useful.
Despite the fact that much of the work of publication has
been off-loaded onto the authors, the price of the book is
very high. Nevertheless, this should not deter libraries and
560
0 VCH
Verlagsgeselischaft mbH, 0-6940 Weinheim. I990
scientists working in the field from buying it, as this is offset
by the wealth of information that is compressed into it.
Kursten Krohn “€3 1031 IE]
Institut fur Organische Chemie
der Technischen Universitat Braunschweig (FRG)
Die Technik der organischen Trennungsanalyse. Eine Einfiihrung. By H. Laatsch. Thieme, Stuttgart 1988. xii, 223 pp.,
paperback, DM 36.00. - ISBN 3-12-722801-8
Owing to the considerable advances that have occurred in
chromatography (thin layer chromatography, column chromatography and gas chromatography), and the relatively
little new progress that has been made in the classical organic
techniques of separation and analysis (“wet chemical methods”), many chemists will take the view that it was not really
necessary to add another survey to the already large number
of review articles on the latter topic. However, the author of
this book intends it to be used by students of experimental
chemistry, who would find a readable and lucid introduction
to the subject very helpful. In meeting this aim he has been
very successful. However, the book should also serve as a
useful introduction for advanced and post-graduate students
engaged in isolating and analyzing natural products, a line of
research which unfortunately tends to be neglected in the
organic chemistry departments of German universities in
comparison with preparative studies.
The first part of the book includes (in Section C, pp. 925) a very detailed description of the “ether separation process”, which is successful for the majority of analytical problems. If the sample contains substances which tend to decompose easily, it is recommended that the separation should be
carried out using derivatives, or by column chromatography.
Attention is also drawn to the possibilities offered by the
color changes exhibited by certain substances at different
pH-values, which make it easier to recognize their presence.
Section D (pp. 26-40) deals with methods for purifying the
crude products of separation and measuring their physical
constants. It is commendable that this section even includes
a detailed account of the purification of solids by crystallization. Crystallization experiments are nowadays often neglected because of the availability of chromatographic separation methods, but they are in fact indispensable for isolating new natural products. The author emphasizes that one
cannot claim to have a pure substance until crystals with a
well-defined melting point have been obtained. A mixture of
two compounds with identical or similar R,-values can
sometimes be mistaken for a pure compound.
The second part of the book (pp. 53- 104) describes the
reactions that can be used to demonstrate the presence of
particular functional groups. Although not all such reactions
are included, the most important ones undoubtedly are, and
attention is drawn to compounds which can interfere with
the analysis. The author describes how the substances isolated are first assigned to particular compound classes, followed by the preparation of the derivatives that are needed
to arrive at an identification. Here again, only the most important derivatives, preferably those which crystallize well,
are described. The preparation of crystalline derivatives
from oily or amorphous compounds is of considerable interest in natural products chemistry, since in many cases the
structures of complex natural products can only be determined by X-ray crystallography. The specimen analytical
reports (Section H, pp. 174-195) are probably unnecessary,
0570-0833/90~0505-0560
8 02.50jO
Angew. Ckem. hi.Ed. EngI. 29 (1990) No. 5
as all students should have already learned in their preparative work how to write reports. In any case, it is not possible
to lay down a report structure which can be applied universally. On the other hand, a useful feature are the exercises
which the student can work through to test his or her knowledge of the methods for detecting functional groups and of
the most important derivatizations for particular classes of
compounds. However, the learning content of the exercises
could have been further increased by including references to
the IR, ‘H NMR and 13CNMR spectra of the compounds.
Despite the fact that at some universities wet analytical
methods are no longer taught, due to the shortening of studies and to the introduction of essential courses on topics such
as spectroscopy and separation techniques, every student
should work through this book. The experimental exercises
and the practical hints are extremely valuable. It is especially
worth mentioning that only a very few errors could be detected. The book has the usual high standard of production of
the Thieme publishing house, and its price is reasonable,
even for students.
Klaus Weinges [NB 1008 IE]
Organisch-Chemisches Institut
der Universitat Heidelberg (FRG)
Dictionary of Alkaloids. Edited by I. W: Southon and J.
Buckingham. Chapman and Hall, London 1989.1161 pp./
index 620 pp., hardcover, L 675.00. -ISBN 0-412-24910-3
The alkaloids, with over 300 structural types and biosynthetic branches, form a group of secondary metabolites
whose variety of structures is unrivalled by any other class of
substances in nature. Since in many cases they show high
toxicity or have other striking physiological effects, they
have long attracted the interest of chemists; their structures
continue to present challenges to analytical, synthetic and
biosynthetic chemists, as befits their great importance in
medicine and research, as toxins, and in chemotaxonomy
and the classification of plants.
As the number of known natural products has grown, the
definition of the term “alkaloid” has become widened to
include not only basic plant substances but also non-basic
nitrogen compounds. The editors of the present book now
take this a step further by including almost all naturally
occurring nitrogen-containing secondary metabolites of
plant, microbial and animal origin; thus the definition is no
longer based on physiological effects, nor on basicity.
In view of this wide definition of alkaloids, it is understandable that the present book contains an enormous number of compounds - about 10000. Thus the extent of this
compilation is greater than in any other similar work. The
only nitrogen-containing natural products that are omitted
or not treated in full are a few simple lower amines, the
nucleobases and nucleosides, and the pterins. Besides true
peptides, the amino acids are also not covered (with only a
few exceptions), but the amines such as tryptamine that are
derived from these by decarboxylation are included. However, the peptide alkaloids are covered thoroughly.
In contrast to other well-known compilations, the alkaloids are not arranged according to the types of organisms
that produce them, nor on the basis of (bio)chemical criteria,
but are instead listed in alphabetical order. In adopting this
method the editors define their aim as that of collecting
together accurate and critical data on all known alkaloids, or
Angew Chem. lnr.
Ed. Engl. 29 (1990) No. 5
at least on those whose structures are known. This necessitates summarizing the information in a concise form; each
entry begins with the name, giving the most usual one where
several alternatives exist, followed by the systematic name.
This is followed by the stereochemical formula according to
the current state of knowledge (showing the absolute configuration where this is known); the stereochemical diagrams
are well-drawn and essentially free from errors. However,
the representation of the sempervirin structure as an N,Nzwitterion seems rather unconventional, in contrast to the
more usual representation as given, for example, for the related alkaloid melinonin E. Following the molecular formula, molecular mass and origin, the entry lists the main physical properties (melting and boiling points, specific rotation,
refractive index) for the parent compound, and often also for
derivatives, together with information on biological activity.
For some alkaloids, however, the last item could have been
more complete; for example, the toxicities of the various
curare alkaloids have been very precisely determined by
Wieiand, whereas this compilation only gives these data for
the main alkaloids, and even here instead of LD 50 values in
most cases there is only a general statement such as “highly
toxic”.
For the many alkaloids whose structures are still unknown, this compilation of data is especially useful, since all
the information contained in the secondary literature has
been extracted from the different sources, critically evaluated, and reduced to a consensus! It would, of course, have
been useful to have spectroscopic data too, but this would
scarcely have been practicable within the predetermined size
of the book. For these the reader is referred to the HEILBRON data bank, from which the present dictionary of alkaloids, like the dictionary of antibiotics from the same publisher, is an extract in book form. This accounts for the
contents of the book being very up-to-date, a fact which is
especially obvious in the literature citations.
Under each entry there is a bibliography, which includes
publications up to the beginning of 1988, and is indexed
under various headings such as isolation, structure determination, spectroscopic data and synthesis. Another very useful item included is the Chemical Abstracts Registry Number, which facilitates making a more extensive literature
search if needed.
Preceding the alphabetically listed information on individual alkaloids there is a 32-page description of the main types
of alkaloids, of which there are about 35. Here nomenclature
and biosynthetic relationships are discussed in a condensed
but very lucid form, with many examples. A list of review
literature is provided with each section.
One can well believe the claim that all alkaloids known up
to the beginning of 1988 are listed: the reviewer can hardly
be expected to check this, of course, and a few tests will have
to suffice. In the main part of the dictionary the simplest
alkaloids, such as benzylamine, are, of course, readily found,
but one can also find those with highly complex structures,
such as leurosin and virotoxin. However, not all of these are
listed under the expected names: whereas dimethyltryptamine and bufotenin are included under these names, serotonin
appears at first glance to be absent, but is then found under
5-hydroxytryptamine. The isomeric psilocin (and also psilocybin), on the other hand, appear under their systematic
names. Yet other alkaloids are not listed separately, but appear under the corresponding parent compounds. As a result
one finds, for example, that only the nitrogen-free compound 12-oxooctadecanoic acid appears as a structural formula, whereas the alkaloid derived from it, lycaonic acid
piperidide, does not.
0 VCH Verlagsgesellschaft mbH, 0-6940
Weinheim, 1990
0570-0~33~90~0505-0S61$02.50/0
561
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