Polysaccharides of micro-organisms (Stacey, M.; Barder, S. A.)

material are then presented, fol- lowed by a discussion of the binary com- poundssuch as the halides, oxides, and sulfides. Special t3^pe compounds as...
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the build up of the multielectmn atoms, and a. hrief description of periodic properties. To this point the treatment of the material is more or less standard. In the next chapter on Valency the subject matter is dominated by the qualitative prcs~,nratiun of the molerubr orl~iial approach to the chemical hond, n.itlr cull~idvmblrernhnsis orr the hvlrrirl naiure of most covalent bonds. ~ h description k of electronegativity here is hrief and does not consider the most recently refined data. The ligand field theory is introduced in the chapter on the Structure and Shape of Moleoules. This chapter also includes two-paragraph thumbnail sketches of experimental techniques for structure determinations. In the next chapter on the Solid State the important structures are discussed, and a section on crystal growth is included. The theoretical section is concluded with chapters on Thermodynamios, Kinetics, and AcidBase theory. The first two are very brief and essentially contain the elements of the theory rather than the practical application of the principles. The descriptive chemistry section oovers the whole periodic table. The elements are discussed in groups as defined by the long form of the periodio table, with separate chapters for hydrogen, the lanthanides, and the actinides. The nontransitional elements are discussed first, except for the inert gases, and Groups I and I1 are divided into two chapters for each group. Chapters on the transitional elements then follow. I n general, the organization of these chapters follows a pattten, in which the electron configurations, radii, ionimtion potentials, electrode potentials, and the physical p r o p erties of the elements are presented in tables. The ohemioal properties of the elements and their preparation from a source materid are then presented, followed by B discussion of the binary compounds such as the halides, oxides, and sulfides. Special type compounds associated with ith pttrticuler group are usually taken up last in the chapter. The molecular orbital theory of bonding is used extensively in the discussion of the structural properties of the molecules. Electrode potentials are used in the discussion of the chemistry, but the use of other thermodynamic data is very Limited. Interspersed with the group chapters, are chapters on the Hydrides, Oxides, Halides, Coordination Compounds, and the Peroxides and Peroxooompounds. These chapters provide a very useful perspective not obtained from the group chapters. In general, the hook is up to date and accurate. There are some questionable statements or omissions, such as the lack of information on polymerked metal ion species in solution, the lack of structural data for Mo(CN)ac4, the acceptance of the still questionable resolution of F e ( C 2 0 p , and comments on the nonexistence of NhIb and M+4ions in aqueous solution. Although a section is included on inorganic nomenclature of complex compounds, when such compounds are named we find reference to purpureo, luteo, and violeo. The Stack ~ystemof nomenclature is not used. No general reference bystem is used,

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Journol of Chemical Education

although if the authors felt that t paparticular discovery or conoept was notedate and name are included worthy, in the text in parentheses. There are no questions or practice exercises included. This hook is a welcome addition to the inorganic literature and will find wide acoeptrtnoe because of it8 up-to-date application of molecular orbital theory to the chemical hond. The authors have a very readable style and have the ability to present complex concepts clearly with a minimum of words.

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EDWINM. LARSEN University of Wiscm'n Madison Polyraccharides of Micro-Organisms

M . Staeey and S. A. Barker, both of the University of Birmingham, England. Oxford University Press, Inc., New York, 1960. ix 228 pp. Figs. and tables. 15 X 22 cm. $4.80.

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Polysaccharide chemistry b advanoing rapidly over a broad front, quite unlike the slower progress whioh was being made only a few years ago. Then, advancement was largely associated with the betterknown plant polysacchariderr such as staroh and cellulose, with the initiation of a formidable advance underway in the chemistry of hemicelluloses, seaweed polysaccharides and a few of the most ahundant polysrtooharides of animala and micro-organisms. Recently, with new and better techniques available, especially those in mieraohemistry, it has been pa* sihle to obtain concrete advances in the general ohemistry and structure of the animal and microbial polysaccharides. Both of these groups of compounds are now under intensive investigation, and much information of a structural, general chemical and biological nature is appearing in the literature. The present volume on the polysacoharides of micro-organisms is not a treatise and makes no attempt to present detailed info~mationin this area. Rather, the purpose of the authors is to present a brief survey, summarizing the existing knowledge regarding the polysscoharides of Gram-positive and Gram-negative bacteria, viruses, rickettsia, moulds, yeasts, y e a d i k e fungi and protozoa. The first five chapters, covering 69 pages, describe briefly the occurrence of certain sugars and groups of sugars and microbial polysaccharides, and the function of polysttceharides, their isolation and the general approach to their structural d a termination. These hrief chapters present a good survey of the subject area. Likewise, the remaining chapters present, in hrief form, the salient developments in the chemistry and biochemistry of specific polysaccharides from micrc-organisms. The reviewer likes the hook and believes that it offers a good u p to-date survey of the subject. Continuation of the present rate of investigative advance will make it desirable and neoessary to have periodic publications of this sort, by which persons interested in biology and macromolecular chemistry may quickly come abreast of this fnccinating and significant field of research.

Nomenclature in the hook is, on the whole, good. I t is hoped that in the future the suthom might work to extend preferred nomenclature. Especially, they should he encouraged to use the term aldobiouronic acid in place of the archaic aldohiuronic acid, because the modified disaccharides referred to have only one uronic acid group. Moreover, the term polyglucosan should be avoided since it signifies a polymer of an intramolecular anhydride. The term glucosan has now been well defined by the American and British Carbohydrate Nomenclature Committees. Polyglucosan, therefore, has a t present no proper nomenclature signxcance in the polysaccharide field. Its place should be taken by the word glucan, whioh signifies a poly~accharide composed only of glucose units. It is also to he hoped that workers will not perpetuate the use of two different names for sugars which are mirror images. Thus, it is not desirable to use both the term ahequose and the term colitose. The two sugars should either be called Dor Lahequose or they should be called D-or Lcolitoee. The hook is generally free of errors; however, on page 43 two basic resins are aid to be in the "sodiumform." ROYL. WHISTLER Purdue University LafayeUe, Indiana

Selertive Toxicity

A d r i a Albert, Australian National Univemity, Canberra, Australia. 2nd ed. John Wilev & Sans. Inc.. New 233 ~ i & and . York, 1960. x tables. 14.5 X 22 cm. $5.50.

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This is a much enlarged second edition of the stimulating work which first appeared in 1951. Chapters have been rewritten with the addition of pertinent new material. New topics have been treated. The prefaoe states that the first 4 chapters are suitable for undergraduate students and that the last 9 chapters are intended for the more advanced student. This hook is not suitable for undergraduates and will prove frustrating at times to the more advanced student. This is disappointing to me since the concept of selective toxicity is well taken and is broadly examined. Four main faults are the basis of this judgment. There are frequent rtmhiguities which would have been avoided by more careful writing. Many generic names are used without accompanying systematic names or structural formulae. References for key statements are frequently not present. Some general ststements are not in accordance with published iofarmation. Indefinite exposition is exemplified on page 7 where the rate of hydrolysis of tetraethylpyrophosphrute is compared with those of certain unspecified "other" phosphate esters. The example of a Van der W&' bond given in Table 1, page 85, is more conventionally restricted

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