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Volume 38, Issue 1
Displaying 1-7 of 7 articles from this issue
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Eiji IMOTO1980 Volume 38 Issue 1 Pages 1-9
Published: January 01, 1980
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSThe organic electronic theory was constructed on the concepts of electron density and delocalization energy, and introduced some hypothetical latent factors to correlate the chemical reactivities of substrates with structures. The latent factors were used successfully to deduce reaction mechanism. However, with accumulation of facts being inexplicable with electronic theory, the theory had to give way to quantum chemistry based on perturbation method. Generally chemical studies take the processes being similar to the life of human being : birth, growth, senility and death. The causes turning the processes might be made obvious by means of case studies.View full abstractDownload PDF (1533K) -
Masazumi IKEDA, Yasumitsu TAMURA1980 Volume 38 Issue 1 Pages 10-21
Published: January 01, 1980
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSThe synthetic utility of the Polonovski reaction has recently been widely explored. Besides classical use in dealkylation of tertiary amines and in the preparation of enamines, it can also be used in the syntheses of a Mannich reagent and many indole alkaloids. Success in the syntheses of vinblastine and related compounds is one of the most important developments. The present review summarizes the synthetic applications of this reaction.View full abstractDownload PDF (1255K) -
Masaru YAMAGUCHI1980 Volume 38 Issue 1 Pages 22-32
Published: January 01, 1980
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSThe total synthesis of macrolides, a group of antibiotics having a variety of large lactone rings, has been one of the most important subjects in the recent synthetic elaborations on natural products. In the present review are described several new lactonization methods which have been used in the syntheses of this class of compounds and some new esterification methods developed in our laboratory, one of which, the method using the mixed carboxylic 2, 4, 6-trichlorobenzoic anhydrides, has been successfully applied to the synthesis of methynolide.View full abstractDownload PDF (1561K) -
Atsuo TANAKA, Saburo FUKUI1980 Volume 38 Issue 1 Pages 33-46
Published: January 01, 1980
Released on J-STAGE: January 22, 2010
JOURNAL FREE ACCESSVarious specific features have been observed with respect to cytological and metabolic properties of microorganisms which can utilize alkanes or methanol as sole carbon and energy source. Based on the fact, a variety of useful cellular components and metabolites, such as amino acids, organic acids, sugar alcohols, polysaccharides, nucleotides, vitamins and coenzymes, antibiotics, enzymes, biomass etc., can be produced by microbial processes utilizing alkanes or methanol as substrate. These products are classified into three groups : (1) The group 1 involves compounds which can be also produced by conventional fermentation of carbohydrates ; (2) The group 2 contains products whose formation from non-sugar substrates is markedly favoured by physiological and metabolic features of microorganisms utilizing such unconventional carbon sources ; (3) The group 3 consists of products to be formed directly from non-sugar substrates. Although these compounds are rarely manufactured from non-sugar substrates on industrial scale at present, the production of compounds belonging to Groups 2 and 3 is not only of academic interest but also of industrial importance. This review summarizes the microbial utilization of alkanes and methanol from fundamental and practical viewpoints.View full abstractDownload PDF (1812K) -
Makoto MISONO, Toshio OKUHARA1980 Volume 38 Issue 1 Pages 47-60
Published: January 01, 1980
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSStereochemical aspects of heterogeneous catalysis have been described. Reactions reviewed here are mostly those which are understandable by the acid-base concepts, e. g., β-elimination over solid acids and bases, halogen exchange and halogenation over metal chlorides, and hydrogenation of dienes and isomerization of olefins over metal oxides and sulfides.
It was attempted to clarify the roles of the structure and the acid-base properties of surface active sites in determining the steric course of reaction as well as stereo- and regioselectivity. Acidbase properties play primary role in the reactions which proceed via ionic intermediates. Surface structure tends to be important when intermediates bond covalently to the surface. In this relation, dynamic behavior of reaction intermediates was also examined.View full abstractDownload PDF (1851K) -
Mechanism and StereochemistryKatsuhiko ICHIKAWA, Masashi INOUE1980 Volume 38 Issue 1 Pages 61-78
Published: January 01, 1980
Released on J-STAGE: January 22, 2010
JOURNAL FREE ACCESSRing-opening of epoxide involves two major subjects of study, positional selectivity and stereochemistry. It appears that the reactions with nucleophiles under basic conditions proceed through SN2 type substitution and no serious problem on both mechanism and stereochemistry remains unsolved. In contrast, the results under acidic conditions are confusing. We have critically discussed the mechanisms proposed so far and shown our conclusion. On the basis of this conclusion together with a new concept of microscopic structure of solvation, the wide range changes of stereochemistry of acid catalyzed solvolysis of stilbene oxide from inversion to retention in binary solvents have been explained. This idea might be applicable to the other types of solvolysis.View full abstractDownload PDF (2229K) -
Kimiaki IMAFUKU1980 Volume 38 Issue 1 Pages 79-82
Published: January 01, 1980
Released on J-STAGE: November 13, 2009
JOURNAL FREE ACCESSThe transmissibility of electronic effects in aromatic compounds of the R-C6H4-CH=CH-G-Y, where G is an aromatic ring and R and Y are a substituent and a reaction center, respectively, is reviewed. In p-styryl-substituted aromatic compounds, transmission factors (π) of the electronic effects through the styryl group are 0.1-0.2.View full abstractDownload PDF (432K)
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