Download or read book Fortschritte der Chemie organischer Naturstoffe Progress in the Chemistry of Organic Natural Products Progr s Dans La Chimie Des Substances Organiques Naturelles written by and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chimie Vegetale Agricole 1899 written by P.E.M. Berthelot and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fortschritte der Chemie Organischer Naturstoffe Progress in the Chemistry of Organic Natural Products Progr s dans la Chimie des Substances Organiques Naturelles written by and published by Springer-Verlag. This book was released on 2013-03-07 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fortschritte der Chemie Organischer Naturstoffe Progress in the Chemistry of Organic Natural Products Progr s dans la Chimie des Substances Organiques Naturelles written by and published by Springer-Verlag. This book was released on 2013-03-07 with total page 639 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fortschritte der Chemie Organischer Naturstoffe Progress in the Chemistry of Organic Natural Products Progr s dans la Chimie des Substances Organiques Naturelles written by and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 469 pages. Available in PDF, EPUB and Kindle. Book excerpt: The properties of proteins are determined not only by the sequence of amino-acid residues in the polypeptide chains, but also by the con figuration of the chains-the way in which the chains are coiled or folded. It is probable that denaturation, the loss of some of the specific properties of a native protein, may in many cases be the result simply of a change in configuration of the polypeptide chains, without any change whatever in the sequence of amino-acid residues. During the past few years great progress has been made in the attack on the determination of the sequence of amino-acid residues in the poly peptide chains of proteins, through the work of SANGER and his collabora tors (Io9, IIO) and of other investigators. There has also been significant progress in the attack on the problem of the configuration of polypeptide chains, largely through the application of the X-ray diffraction technique.
Download or read book Fortschritte der Chemie Organischer Naturstoffe Progress in the Chemistry of Organic Natural Products Progr s dans la Chimie des Substances Organiques Naturelles written by and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 429 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fortschritte der Chemie Organischer Naturstoffe Progress in the Chemistry of Organic Natural Products Progres dans la Chimie des Substances Organiques Naturell es written by and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 561 pages. Available in PDF, EPUB and Kindle. Book excerpt: Substances belonging to this group of organic compounds are wi,lely distributed in Nature, being found in plants, both higher and lower fungi and, upto the present time, in one animal source, sheep wool-fat. For a long time no real differentiation was possible between the tetra- and penta cyclic triterpenes and the sterols. Then the two latter became disting uishable by their selenium. ·dehydrogenation products, i. e. , picene and naphthalene derivatives from the pentacyclic triterpenes and DIELS' hydrocarbon from the sterols. It is now apparent that those compounds yielding predominantly I: 2: 8-trimethylphenanthrene on dehydro genation represent yet another class, and this property is regarded as typical of the tetracyclic triterpenes. The group contains both C and C 30 3l compounds and, although the latter fall outside RUZICKA'S strict definition of triterpenes (I42), it seems desirable to permit this deviation. Members with thirty-two carbon atoms may well be discovered in due course. In a most· valuable account of the triterpenes written in I949, JEGER. (II3) was able to summarize all that was known about the tetra cyclic group in a very small compass. Most of the work discussed in the present article has been published during the last five years and in that time the structures of some twenty compounds have been elucidated. Of outstanding importance is the revelation of close structural relation ships tQ the steroids, and the presence of C and C side-chains, skeletally 8 9 identical with those of cholesterol and ergosterol.
Download or read book Fortschritte der Chemie Organischer Naturstoffe Progress in the Chemistry of Organic Natural Products Progr s dans la Chimie des Substances Organiques Naturelles written by and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 235 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Gay Lussac written by Maurice P. Crosland and published by Cambridge University Press. This book was released on 2004-02-12 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first work to examine critically both the scientific work and the man behind it, and as well as providing the historian of science with a comprehensive account of the life and work of a major nineteenth-century scientist, the book will also be of value to the social and economic historian.
Download or read book Fortschritte der Chemie Organischer Naturstoffe Progress in the Chemistry of Organic Natural Products Progr s Dans La Chimie Des Substances Organiques Naturelles written by and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 547 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fortschritte der Chemie Organischer Naturstoffe Progress in the Chemistry of Organic Natural Products Progr s dans la Chimie des Substances Organiques Naturelles written by and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Catalogue of the Library of the Chemical Society Arranged According to Authors with a Subject Index written by and published by . This book was released on 1903 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chimie Appliqu e L griculture written by Jean-Antoine-Claude Chaptal (comte de Chanteloup) and published by . This book was released on 1829 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fortschritte der Chemie Organischer Naturstoffe Progress in the Chemistry of Organic Natural Products Progr s Dans la Chimie des Substances Organiques Naturelles written by and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: In agreement with SCHLENK (I78) "nucleotide" is here taken to mean a phosphoric ester of an N-glycoside of a heterocyclic base. Although they fall outside the scope of this definition, phosphorylated derivatives of riboflavin are added in recognition of their close relation to the main body of nucleotides. A complete review of even the organic chemistry of nucleotides and their derivatives would now form a substantial monograph. The smaller and less characteristic fragments of the nucleotides, namely the hetero cyclic bases, the component sugars and the derived sugar phosphates, are therefore excluded from this article. * Their chemistry is of longer standing and is covered in standard works. On the other hand knowledge of the "nucleosides", the N-glycosides of heterocyclic bases, has expanded very considerably in recent years and an account of the relevant work is therefore included. With regard to the nucleotides themselves attention is focussed on work published in the last few years leading to improved characterisation, more exact structural knowledge and increased availa biIity. Only such enzymatic experiments as bear direct1y on structural problems are discussed and therefore much fascinating work by KALCKAR, FRIEDKIN et al. and by KORN BERG has been omitted. I t would be unthinkable to present a review on nucleotides without mentioning that the foundations of the subject were laid by P. A. LEVENE. His monograph with BASS (I36) was published in 1931 and two reviews by LYTHGOE (I50, I5I) cover the intervening period until 1944.
Download or read book Fortschritte der Chemie Organischer Naturstoffe Progress in the Chemistry of Organic Natural Products Progr s dans la Chimie des Substances Organiques Naturelles written by and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sulfonium compounds have been known to the organic chemist for almost 90 years. During most of this period they remained curiosities, well suited for didactic purposes to illustrate certain similarities to ether adducts and to organic ammonium compounds. Their exploration remained largely in the academic realm, because no unusual practical applications were found in spite of a steady increase in the attention paid to them. An event that occasionally puts a class of compounds into the center of interest is the recognition of its occurrence in nature and of special biological significance. The first natural sulfonium compound was discovered less than 20 years ago, somewhat by chance rather than as the climax of some coveted biochemical problem. Gradually, however, the unique role of sulfonium compounds, especially of S-adenosyl methionine, in enzymatic group transfer reactions such as trans methylation was recognized, and the recent upsurge of interest has been exceptional. The present review is directed toward an interpretation of the properties and functions of biological sulfonium compounds with frequent reference to their structural chemistry. The data presented here may suggest novel or improved analytical techniques and new interpretations of the mechanism of group transfer. Furthermore, a stimulus may be derived for the design of sulfonium compound analogues. The availability of competitive analogues of biochemical key compounds has aided in the understanding of the function of virtually all metabolic intermediates, prosthetic groups of enzymes, vitamins, amino acids, and other compounds. The pattern will be similar in sulfonium biochemistry.
