Hermann Emil Fischer
Hermann Emil Fischer
Hermann Emil Louis Fischer
9 October 1852
Euskirchen, Rhine Province
|Died||15 July 1919 (aged 66)|
|Alma mater||University of Bonn|
University of Strasbourg
|Known for||Study of sugars & purines|
|Institutions||University of Munich (1875–81)|
University of Erlangen (1881–88)
University of Würzburg (1888–92)
University of Berlin (1892–1919)
|Doctoral advisor||Adolf von Baeyer|
|Doctoral students||Alfred Stock|
Walter A. Jacobs
Hermann Emil Louis Fischer FRS FRSE FCS (9 October 1852 – 15 July 1919) was a German chemist and 1902 recipient of the Nobel Prize in Chemistry. He discovered the Fischer esterification. He also developed the Fischer projection, a symbolic way of drawing asymmetric carbon atoms. He also hypothesized lock and key mechanism of enzyme action. He never used his first given name, and was known throughout his life simply as Emil Fischer.
Fischer was born in Euskirchen, near Cologne, the son of Laurenz Fischer, a businessman, and his wife Julie Poensgen. After graduating he wished to study natural sciences, but his father compelled him to work in the family business until determining that his son was unsuitable. Fischer then attended the University of Bonn in 1871, but switched to the University of Strasbourg in 1872. He earned his doctorate in 1874 under Adolf von Baeyer with his study of phthaleins, and was appointed to a position at the university.
After eight years at Strasbourg, he was appointed to the chair of chemistry successively at the universities of Erlangen (1882) and Würzburg (1885). In 1892 he succeeded von Hofmann as professor of chemistry at the University of Berlin.
Fischer married Agnes Gerlach in 1888. She died seven years later leaving him a widower with three sons. The younger two died during their military service in World War I. His oldest, Hermann, became an organic chemist. He died in Berlin on July 15, 1919.
In 1875, the year following his engagement with von Baeyer, he published his discovery of the organic derivatives of a new compound of hydrogen and nitrogen, hydrazine. He investigated their derivatives, establishing their relation to the diazo compounds, and he noted the readiness with which they entered into combination with other substances, giving origin to a wealth of hitherto unknown compounds. Of such condensation products undoubtedly the most important are the hydrazones, which result from the interaction with aldehydes and ketones. His observations, published in 1886, that such hydrazones, by treatment with hydrochloric acid or zinc chloride, yielded derivatives of indole, the parent substance of indigo, were a confirmation of the views advanced by von Baeyer on the subject of indigo and the many substances related to it.
He next turned to the fuchsine (then called "rosaniline") magenta dyes, and in collaboration with his cousin Otto Fischer, he published papers in 1878 and 1879 which established that these dyes were derivatives of triphenylmethane. Emil Fischer's next research was concerned with compounds related to uric acid. Here the ground had been broken by von Baeyer, but Fischer greatly advanced the field of knowledge of the purines. In 1881 and 1882 he published papers which established the formulae of uric acid, xanthine, caffeine (achieving the first synthesis), theobromine and some other compounds of this group. After purine itself was isolated, a variety of derivatives were prepared, some of which were patented in view of possible therapeutical applications.
Fischer is particularly noted for his work on sugars. Among his early discoveries related to hydrazine was that phenylhydrazine reacted with sugars to form 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. Later, among other work, he is noted for the organic synthesis of D-(+)-glucose. He showed how to deduce the formulae of the 16 stereoisomeric glucoses, and prepared several stereoisomerides, helping to confirm confirming the Le Bel–Van 't Hoff rule of the asymmetric carbon atom.
In the field of enzymology, Fischer is known for his proposal of "the lock and key" model as a mechanism of substrate binding.
Fischer was also instrumental in the discovery of barbiturates, a class of sedative drugs used for insomnia, epilepsy, anxiety, and anesthesia. Along with the physician Josef von Mering, he helped to launch the first barbiturate sedative, barbital, in 1904. He next carried out pioneering work on proteins. By the introduction of new methods, he succeeded in breaking down the complex albumins into amino acids and other nitrogenous compounds, the constitutions of most of which were known, and by bringing about the recombination of these units, he prepared synthetic peptides which approximated to the natural products. His researches made from 1899 to 1906 were published in 1907 with the title Untersuchungen über Aminosauren, Polypeptides und Proteine.
In 1897 he put forward the idea to create the International Atomic Weights Commission. Fischer was elected a Foreign Member of the Royal Society (ForMemRS) in 1899. He was awarded the 1902 Nobel Prize in chemistry "in recognition of the extraordinary services he has rendered by his work on sugar and purine syntheses."
Many names of chemical reactions and concepts are named after him: