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FISCHER

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Originally appearing in Volume V10, Page 426 of the 1911 Encyclopedia Britannica.
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FISCHER , See also:

ERNST substances which he named osazones, and which, being highly crystalline and readily formed, served to identify such carbohydrates more definitely than had been previously possible. He next turned to the rosaniline dyestuffs (the See also:magenta of See also:Sir W. H. See also:Perkin), and in collaboration with his See also:cousin See also:Otto Fischer (b. 1852), then at See also:Munich and afterwards See also:professor at See also:Erlangen, who has since identified himself mainly with the compounds of this and related See also:groups, he published papers in 1878 and 1879 which indubitably established that these dyestuffs were derivatives of triphenyl methane. Fischer's next See also:research was concerned with compounds related to uric See also:acid. Here the ground had been broken more especially by von See also:Baeyer, but practically all our knowledge of the so-called See also:purin See also:group (the word purin appears to have been suggested by the phrase purum uricum) is due to Fischer. In 1881–1882 he published papers which established the formulae of uric acid, xanthine, See also:caffeine, theobromine and some other compounds of this group. But his greatest See also:work in this See also:field was instituted in 1894, when he commenced his See also:great See also:series of papers, wherein the compounds above mentioned were all referred to a nitrogenous See also:base, purin (q.v.). The base itself was obtained, but only after much difficulty; and an immense series of derivatives were prepared, some of which were patented in view of possible therapeutical applications.' These researches were published in a collected See also:form in 1907 with the See also:title Untersuchungen in der Puringruppe (1882–1906). The first See also:stage of his purin work successfully accomplished, he next attacked the See also:sugar group. Here the See also:pioneer work was again of little moment, and Fischer may be regarded as the See also:prime investigator in this field.

His researches may be taken as commencing in 1883; and the results are unparalleled in importance in the See also:

history of organic See also:chemistry. The chemical complexity of these carbohydrates, and the difficulty with which they could be got into a manageable form—they generally appeared as syrups—occasioned much experimental difficulty; but these troubles were little in comparison with the complications due to stereochemical relations. However, Fischer synthesized See also:fructose, See also:glucose and a great number of other sugars, and having showed how to deduce, for instance, the formulae of the i6 stereoisomeric glucoses, he prepared several stereoisomerides, thereby completing a most brilliant experimental research, and simultaneously confirming the See also:van't Hoff theory of the See also:asymmetric See also:carbon See also:atom (see STEREO-See also:ISOMERISM). The study of the sugars brought in its See also:train the See also:necessity for examining the nature, properties and reactions of substances which bring about the decomposition known as See also:fermentation (q.v.). Fischer attacked the problem presented by ferments and enzymes, and although we as yet know little of this complex subject, to Fischer is due at least one very important See also:discovery, viz. that there exists some relation between the chemical constitution of a sugar and the ferment and See also:enzyme which breaks it down. The magnitude of his researches in this field may be gauged by his collected papers, Untersuchungen giber Kohlenhydrale and Fermente (1884–1908), pp. viii.-I--912 (See also:Berlin, 1909). From the sugars and ferments it is but a See also:short step to the subject of the proteins, substances which are more directly connected with See also:life processes than any others. The chemistry of the proteins, a subject which bids See also:fair to be Fischer's great lifework, presents difficulties which are probably without equal in the whole field of chemistry, partly on See also:account of the extraordinary chemical complexity of the substances involved, and partly upon the See also:peculiar manner in which chemical reactions are brought about in the living organism. But by the introduction of new methods, Fischer succeeded irl breaking down the complex albuminoid substances into amino acids and other nitrogenous compounds, the constitutions of most of which have been solved; and by bringing about the re-See also:combination of these See also:units, appropriately chosen, he prepared synthetic peptides which approximate to the natural products. His methods led to the preparation of an octadeca-peptide of the molecular See also:weight 1213, exceeding that of any other synthetic See also:compound; out even this compound falls far short of the simplest natural peptide, which has a molecular weight of from 2000 to 3000, He considers, however, that the See also:synthesis of more complex products is only a See also:matter of trouble and cost. His researches made from 1899 to 1906 have been published with the title Untersuchungen fiber Aminosauren, Polypeptides and Proteine (Berlin, 1907). The extra-See also:ordinary merit of his many researches has been recognized by all the important scientific See also:societies in the See also:world, and he was awarded the See also:Nobel See also:prize for chemistry in 1902 Under his See also:control the laboratory at Berlin became one of the most important in existence, and has attracted to it a See also:constant stream of brilliant pupils, many of whom are to be associated with much of the experimental work indissolubly connected with Fischer.

End of Article: FISCHER

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