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Book Review Boron-Nitrogen Compounds. Vol. VI of the Series УAnorganische und allgemeine Chemie in EinzeldarstellungenФ. By K. Niedenzu and J. W. Dawson

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redox potential E’o at p H 7.0 and 25 “ C is -0.057 V (ferredoxin: -0.41 V); only one electron is given up on oxidation
(as in ferredoxin). Like ferredoxin and thioredoxin, rubredoxin contains many more acidic amino acids than basicones :
12 Asp, 6 Glu, compared with only 4 Lys. N o specific reactions of rubredoxin have been found as yet. It catalyses the
ferredoxin-catalysed reactions (e.g . the reduction of NADP
by hydrogen and hydrogenase), but the reaction rates are
only about 20 % of those obtainable with ferredoxin. / Proc.
nat. Acad. Sci. USA 54, 193 (1965) / -Ha. [Rd 414/623 IE]
Fulvene containing less than 2 % of impurities is formed in
74 % yield when a mixture of the acetoxymethylcyclopentadienes ( I ) and (2) is allowed to react with the equivalent
quantity of triethylamine. H. Schaltegger, M . Neuenschwander, and D . Meuche prepared ( I ) and (2) from cyclopentadienylsodium and chloromethyl acetate in tetrahydrofuran
~ C H ~ - O - R
P H 2 - O -
(I), R = -CO-CH3
( 3 ) , R = -CH3
(2), R = -CO-CH3
( 4 ) , R = -CH3
at -30 “ C (yield 30 %). N o fulvene is obtained from a mixture
of (3) and (4) under the same conditions. / Helv. chim. Acta
48, 955 (1965) J -Bu.
[Rd 437/646 IE]
The biosynthesis of the biotin enzymes from apoenzyme and
biotin has been studied by Th. Hopner and J. Knappe. They
used the P-methylcrotonyl-CoA carboxylase from Achromobacter 1Vs-W. Even under oprimal growth conditions, this
biotin-auxotrophic organism (grown with isovaleric acid as
the only source of carbon) synthesizes a p-methylcrotonylCoA carboxylase in which only 80 to 9 0 % of the active
centers are occupied by biotin. In the presence of a holocarboxylase synthetase which had been concentrated by a
factor of 150, the remaining apo-centers could be saturated
with biotin, this saturation being accompanied by stoichiometric regeneration of carboxyl reactivity. The course of the
reaction [Equations (1) and (2)] was demonstrated by the
following synthetase-catalysed reactions:
synthetase
,.
+
biotin + ATp r-=.
biotinyl -AMP pyrophosphate
biotinyl - A M P S apoenzyme
synthetase
--+
holoenzyme + AMP (2)
a) ATP-dependent formation of biotin hydroxamate from
biotin and hydroxylamine; b) biotin- and hydroxylaminedependent formation of AMP from ATP; c) biotin-dependent exchange between ATP and 3*P-pyrophosphate;
d) synthesis of ATP from biotinyl -AMP and pyrophosphate;
e) incorporation of biotin from biotinyl -AMP into P-methylcrotonyl-CoA carboxylase. / Biochem. Z . 342, 190 (1965)
-HO.
[Rd 415,’624 IE]
BOOK REVIEWS
Cyclooctatetraen (Cyclooctatetraene). By G. Schroder. Monograph No. 73 to “Angewandte Chemie” and “Chemie-Ingenieur-Technik”.VerlagChemieGmbH.Weinheim/Bergstr.
1965. 1st Edit.,viii
88 pp.. many illustr., cardboard
DM 23.- (about $6.-).
In recent years cyclooctatetraene has been the subject as well
as the starting material of a large number of investigations,
and these are comprehensively covered in this monograph. A
description of the syntheses and a short chapter on the structure is followed by much the longest section, which is devoted
to the chemical properties of eyclooctatetraene and its derivatives. The following are discussed in detail: reduction and
oxidation products of cyclooctatetraene, its behavior towards
acids, bases, and free radicals, the adducts formed with
carbenes, halogens, and dienophiles, its organometallic complexes, valence-bond isomers, substitution products, and
dimers with particular emph sis on bullvalene (obtainable
from them). Finally there are selected recipes for preparation
of 20 derivatives. The authm restricts himself to short but
clear restatement of the literature, which is considered up to
the middle of 1964. Yet owing to the modernity ofthe subject,
several sections already need expansion or correction (inversion of cyclooctatetraene, its bromination, and the structure of the dimer of m.p. 53 “C). Anyone interested in the unusually varied chemistry of cycloctatetraene will find this
volume an ideal source of information. Unfortunately the
price of this little book is not in proportion to its size.
W. Roth
[NB 461/314 IE]
+
Die komplexometrischeTitration (Complexometric Titration).
Volume 45 of “Die chemische Analyse” (Chemical Analysis). By G. Schwarzenbach and H. Flaschka. Ferdinand
Enke Verlag, Stuttgart 1965. 5th revised Edit., xvi+ 339
pp.. 42 figs., 12 tables, 48.- D M (about$ 12.-).
The present fifth edition of this part of “Diechemische Analyse” (Chemical Analysis) appears 20 years after the introduction of complexometric titration and 10 years after the first
edition. Written in collaboration with H. Fluschka it has become a completely new book. The volumetric procedure
established by G. Schwarzenbach is characterized by the use
430
of specific complex-formers and indicators for metal ions, and
its explosive development has necessitated an expansion of
the text from 119 to 339 pages. Division of the text into two
parts of equal length - one theoretical and the other practical - has been maintained. The first part contains general
information about titration reagents, the theory of the course
of the reactions and the mode of action of dye and fluorescent
indicators in complexometry, the methods of visual and
instrumental end-point determination and the various types
of titration, their accuracy and selectivity. In the second part
practical details are given, first for the preparation of volumetric and indicator solutians, then for complexometric
determination of almost all the elemnts; in the last section
is described the determination and masking of metals in a
most imaginative way by manifold combinations of formation
and fission of kinetically labile metal complexes. (The determination of non-metals, e.g. fluorine, should, however, be
considered critically.) The literature up to the end of 1963 is
cited in 1437 references, arranged alphabetically in groups according to the year of their appearance.
In its new expanded form this book has become the standard
work for complexometric titrations. It is a valuable adviser
for analytical practice and is exciting reading for all who are
interested in the theoretical foundations of chemistry in aqueous solutions.
F. See2
[NB 463/316 IE]
Boron-Nitrogen Compounds. Vol. VI of the Series “Anorganische und allgemeine Chemie in Einzeldarstellungen”. By
K . Niedenzu and J. W. Dnwson. Springer-Verlag, BerlinHeidelberg-New York 1965. 1st Edit., viii + 176 pp.,
numerous figs., linen 27.- DM (about $7.-).
Several books have recently appeared on the chemistry of
boron. The present one concerns boron-nitrogen compounds,
which have been extensively studied during the last 10 years
or so, and to which the authors have made numerous contributions. Six chapters are devoted to amine-boranes (borazanes), aminoboranes (borazenes), borazoles, BNC heterocycles, and boron nitrides. Additionally there is a short section on IlB nuclear magnetic resonance. Numerous tables
Angew. Chem. internat. Edit. j Vol. 5 (1966)
No. 4
and recipes for the preparation of important starting materials
complete the text. A useful author index (12 pp.) is to be contrasted with too short a subject index (5 pp.).
This readable book undoubtedly fulfils its object, as a n introduction into the chemistry of boron-nitrogen compounds,
and it provides stimulation for further development thereof.
However, the chemistry of the borazoles and BNC heterocycles, e. g . the borazarenes deserves more detailed treatment,
and so do the results obtained in the laboratories of W. M .
Michailow and V. I . Zacharkjn. It is mainly the work of the
last five years that is discussed. The reviewer does not always
agree with the authors’ views, and study of the book makes it
clear that more quantitative work is needed in order to
provide a firm thermodynamic, kinetic, and structural basis
for further discussions and t o place the present plausible
working hypotheses on a firmer basis.
H. Niith
[NB 465/318 IE]
Die Bestandteile der Lebensmittel (The Constituents of
Foodstuffs). Volume I of the Series “Handbuch der Lebensmittelchemie” (Handbook of Foodstuffs Chemistry).
Edited by J . Schormiiller. Springer-Verlag,, Berlin-Heidelberg-New York 1965. 1st Edit., xxviii + 1288 pp., 136 figs.,
linen D M 298.- (about $ 75.-). Subscription price
D M 238.40 (about $ 60.-).
After 32 years the first volume of the new edition of the Handbuch der Lebensmittelchemie (Handbook of Foodstuffs
Chemistry) has appeared, on the constituents of foodstuffs.
This long interval has had the inevitable consequence that
only the form of the old book is preserved, the text having
been largely rewritten, yet strict control by the editor has ensured that the total number of pages is somewhat less than in
the previous edition.
For treatment of the 24 chapters of this volume experts in
specialized fields have been enlisted as well as specialists in
general foodstuffs chemistry. References to the literature are
given at the end of each chapter, and some of the authors have
included references up to 1964.
Chapter 1 treats the history of food science from prehistory
to the 20th century. This review is certainly comprehensive,
including control and research, and has some very telling illustrations. In the next chapter 0. Hog1 expounds the objectives of foodstuffs science. The most important aim is to disclose and evaluate the composition of foods; the recognition
and removal of injurious components are recorded in further
sections of this chapter, and in a very shorf space but quite
comprehensively a further section treats the importance of
water as a food constituent, including its place in fresh and
preserved foods. Additionally H . Langendorf’ discusses inorganic cations and anions which are essential for the organism, sometimes in large quantities and sometimes in traces;
their function in metabolism is also noted; and five tables
give information about the content of essential ions in the
most important foods.
The chapter on amino acids, peptides, and other nitrogen
compounds seems to the reviewer to be too detailed: not only
the chemical properties and physiological importance, but
also the occurrence of rare amino acids, are reported, even for
products that are not foods. The same applies to the discussion of peptides, but the treatment of proteins is better related to the main theme. There is, however, no reference to
the manifold changes undergone by methionine or the unpleasant smell and taste that can result from its decomposition
products.
The chapter o n fats, lipids, waxes, and resins provides a short
but very valuable review. The most important saturated and
unsaturated fatty acids are described, and also glycerides,
phosphatides, sphingolipids, and other possible secondary ingredients. It should, however, be noted that :/-sitosterol (pp.
338 and 345) has meanwhile been recognized as a 1 : 1 mixture of p-sitosterol and campesterol. Finally the author describes the natural and technological changes undergone by fats.
Angew. Chem. internut. Edit.
,
Vol. 5 (1966)
Nu. 4
The isolation and composition of essential oils is treated by
K. Herrmann. The most important mono- and sesqui-terpenes
are mentioned, as well as other constituents such as acids,
esters, ketones, and sulfur compounds that determine the taste.
In the chapter on carbohydrates and glycosides Almut Klemer
describes the chemistry and analysis of sugars, and also sugar
esters, amino sugars, pectins, algal products, and carbohydrate-protein compounds. The chapter concludes with seven
tables giving the most important constants of these compounds. The authoress reports also on 0-,N-, and S-glycosides. A few inaccuracies have crept in concerning saponins :
or-amyrin is derived from ursane, and P-amyrin from oleanane (p. 527); aescin is a n oleanane derivative, its structure
having been determined in 1963 (p. 529); the triterpene acid
of ursane type is named ursolic acid (pp. 530 and 1284).
H. Endres discusses the most important tannins. Unfortunately, except for passing mention of the catechins of tea and
coffee beans, this chapter contains no reference to foodstuffs ;
but the omission is rectified to some extent in the next chapter
where K. Herrmann treats plant phenolics in foodstuffs.
The following chapter, by E. Beyer, describes the isolation,
constitution, and detection of natural dyes, in particular
carotenoids, quinones, flavanoids, anthocyanins, and some
porphyrins. It is expanded by R . Humm in a good review of
the chemistry of haemoglobin and myoglobin. The chapter
on carboxylic acids, esters, carbonyl compounds, and alcohols shows a welcome orientation towards the requirements
of foodstuffs chemistry. However, the formulae of the two
optically active tartaric acids (p. 778) d o not agree with the
latest information: the formula described as D-(+)-tartaric
acid i s that of r-(+)-tartaric acid, and that described as L-(-)tartaric acid is D-(-)-tartaric acid.
K. Myrbiick makes a valuable contribution to the general field
of enzymes. It is supplemented by H . Mohler’s description of
the importance of enzymes in foodstuffs technology and in the
formation of aromatic ingredients, also by H. Sommer’s report o n commercially prepared enzymes and their use in manufacture and analysis of foodstuffs. The chapter on vitamins
deals first with their stabilization and with procedures for
their analysis; it then treats the individual vitamins in alphabetical order, including their mode of action. There is, however, no mention of the artefact nature of cyanocobalamin in
the discussion of vitamin B12 or of the present-day preference
of vitamin D3 over vitamin D2. The chapter on chemical additives treats preservatives very thoroughly, including their
properties, uses, and modes of action. The discussion of dyes
for foodstuffs records both the old use of saffrom and curcuma, and the toxic effects of certain azo dyes. There follows
a list of permitted dyes in accordance with the data of the
Farbstoffkommission of the Deutsche Forschungsgemeinschaft.
In the last chapter S. W. Souci and E. Mergenthuler report on
all other chemical additives, such as antioxidants, synergists
and complex-formers, color improvers and bleaching agents,
thickening and gelling agents, surface-active materials and
materials having a physical effect, coatings, insecticides, and
herbicides. The list is comprehensive and provides a good
orientation on the properties of the individual compounds.
The book ends with a subject index running to 65 pages.
The publishers have produced the book to their usual high
standard. The printing is almost free from error, and the
formulae cannot be misinterpreted (with very few exceptions,
e.g. gossypol, p. 351). The editor and the publishers are to be
congratulated on a noteworthy achievement.
[NB 462!315 IE]
C. H . Brieskorn
Selected Papers on Molecular Genetics. A Collection of
Reprints with Introductory Material. Vol. 1 of the Series
“Perspectives in Modern Biology - A Series of Reprint
Collections”. By J.H . Tuylor. AcadeniicPress Inc., New York
1965. 1st Edit., xii+ 650pp., bound $ 9.-, paper back $5.95.
In few parts of biochemistry has development been as lively
during recent decades as in genetics with all its far-reaching
43 1
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