摘要:

AbstractSubstances with blood‐group ABH(0) specificity are not confined to human red blood cells. Rather, such substances are ubiquitous antigenic surface structures which Nature has preserved throughout the phylogenetic development from microbes to man. — It could be shown experimentally that so‐called “pre‐existing natural” antibodies can result from inapparent immunization by these widely distributed antigens. — The blood‐group specific structures of bacteria are chemically closely related to the determinant structures of the human blood‐group ABH(0) glycoproteins. The situation is more complicated for the blood‐group active substances from higher plants; these give extraordinary immunochemical reactions and two of their blood‐group specific monosaccharides precipitate antibodies. — Recently the nature of the M and N blood‐group antigens of erythrocyte surfaces has been elucidated. They are the main antigens of the second of at least 14 human blood‐group systems. These substances, which are glycoproteins, are also excellent myxovirus receptors and inhibitors. The NN antigen is the first reported physically homogeneous, chemically defined and highly blood‐group active cell surface structure of human origin. As surface structures, blood‐group active substances appear to be frequently endowed with receptor properties in addition to t

ISSN:0570-0833    

DOI:10.1002/anie.196609091

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

摘要:

AbstractThe present article shows the extent to which isotope effects are likely to be encountered in the use of isotope techniques and what problems are studied with primary and secondary isotope effects. By way of example, the results of studies on E2 reactions, particularly in the Hofmann degradation, are discussed, followed by a discussion of some “analytical isotope effects”. Finally, the problems encountered and the information that can be obtained from isotope effects studies on enzyme reactions, and the advantages and disadvantages of competitive and non‐competitive techniques are described. In addition to a survey of isotope effects in dehydrogenase reactions, new isotope effects encountered in the dehydrogenation of T‐labeled alcohols are r

ISSN:0570-0833    

DOI:10.1002/anie.196609201

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

摘要:

AbstractConsiderable progress has been made in the past decade in the preparation and chemistry of allene. The present article is a critical review of this progress, and shows that owing to the particular structure of allene (two double bonds situated in mutually perpendicular planes), the chemistry of this compound is unique in many respects.

ISSN:0570-0833    

DOI:10.1002/anie.196609331

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

摘要:

AbstractThe chemistry of polyfluorinated ketones has recently received a great deal of attention.A. Ya. Yakoubovich, Usp. Chim.25, 3 (1956).H. P. BraendlinandE. T. McBeein: Advances in Fluorine Chemistry. Butterworths, London 1963, Vol. 3, p. 1.The review byBraendlinandMcBee[2] does not deal only with perfluorinated ketones; moreover, though published in 1963, it is already outdated. The papers discussed in [1,2]will not be reviewed in the present article.. The carbonyl and imino groups of the fluorinated ketones and their imines react in many different ways. In particular, the electron‐attracting perfluoroalkyl groups intensify the electrophilic properties and weaken the nucleophilic properties of the carbonyl group. The perfluoroalkyl group also hinders the heterolytic removal of the hydroxyl group from adducts by reducing the stability of the carbonium ion . The increased electrophilicity of the carbonyl group and the increased stability of the addition products leads not only to a change in reactivity in the characteristic ketone reactions, but also to numerous new reactions which are not observed with non‐fluorinated ketones. Thus it is possible to synthesize a wide variety of fluoroorganic compounds from perfluorinated ketones.We have been concerned mainly with hexafluoroacetone, since in addition to being the most readily available and simplest perfluorinated ketone, this is also a typical representative of this class of compoun

ISSN:0570-0833    

DOI:10.1002/anie.196609471

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196609572

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196609581

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196609591

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196609602

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196609612

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY

ISSN:0570-0833    

DOI:10.1002/anie.196609621

出版商:Hüthig&Wepf Verlag    

年代:1966

数据来源: WILEY