Fischer, Emil structure

Fischer, Emil Hermann (1852-1919), German chemist and witmer of the Nobel Prize in Chemistry 1902 for his work on the structure and synthesis of sugars and purines. Between 1899 and 1908, he made... 

Fischer, Emil Hermann (1852-1919) German organic chemist. Fischer studied many compounds of biological interest. He is sometimes referred to as the father of biochemistry. In 1874 he discovered phenylhydrazine. He studied peptides, purines and sugars very thoroughly. His work on purines (a name he coined) led to the synthesis of many compounds such as caffeine and purine. In his early work he put forward incorrect structures but by 1897 he and his colleagues had established the correct structures. Fischer was awarded the 1902 Nobel Prize for chemistry for his work on purines and sugars. 

Of all the monosaccharides d (+) glucose is the best known most important and most abundant Its formation from carbon dioxide water and sunlight is the central theme of photosynthesis Carbohydrate formation by photosynthesis is estimated to be on the order of 10 tons per year a source of stored energy utilized directly or indi rectly by all higher forms of life on the planet Glucose was isolated from raisins m 1747 and by hydrolysis of starch m 1811 Its structure was determined in work culmi nating m 1900 by Emil Fischer... 

In contrast to the alkaloids mentioned so far, heterocyclic mesomeric betaines are defined as neutral conjugated molecules which can be represented only by dipolar structures in which both the negative and the positive charges are delocalized within the rr-electron system (38JCS824, 85T2239). The first heterocyclic mesomeric betaine was prepared unknowingly by Emil Fischer (1882LA316). The real structure remained unknown... 

Emil Fischer developed a strong interest in the structural requirements for enzyme activity as the result of effects of changes in the structures of the a-and -methyl glucosides on their properties as substrates for the enzymes invertin and emulsin, which, as we have seen, he had shown to be a- and yS-glucosidases, respectively. As already mentioned, he was fascinated in 1895 by the fact that emulsin had no effect on either the a- or /2-methyl xylosides (33). In a 1912 publication with Karl Zach (34), he reported that -methyl 6-deoxyglucoside was hydrolyzed by emulsin and wrote ... 

Lipid A, molecular structure of, 50,211 -276 Liquid chromatography, high-performance, of carbohydrates, 46,17-72 addendum to, 46, 327-329 Lock and key concept for enzyme specificity, how Emil Fischer was led to, 50,1 -20... 

In addition to these physical studies at the Bureau, Tipson was able to return to his synthetic interests, both alone and in collaboration with other staff members. He was especially pleased to prepare D-talose in crystalline form, an accomplishment that had eluded Emil Fischer. Pursuing his longstanding interest in the reaction of sulfonic esters with iodide and following an earlier observation that the tetratosyl ester of erythritol is converted into butadiene by the action of sodium iodide and zinc, he demonstrated (with A. Cohen) that nonterminal unsaturation may be conveniently introduced into alditol derivatives by reaction of contiguous secondary sulfonates with sodium iodide and zinc dust in boiling A.A-dimethylformamide. This Tipson-Cohen reaction subsequently proved of great utility in other hands for the conversion of more complex carbohydrate structures into vicinal dideoxy derivatives. 

Geison, "Scientific Change." J. S. Fruton, "Contrasts in Scientific Style Emil Fischer and Franz Hofmeister, Their Research Schools and Their Theories of Protein Structure," Proceedings of the American Philosophical Society 129 (1985) 313370 also see, Fruton, "The Liebig Research Group, a Reappraisal," ibid., 132 (1988) 166 Holmes, "Complementarity," 121164 and J. B. Morrell, "The Chemist Breeders ... 

Fruton, Joseph S. "Contrasts in Scientific Style Emil Fischer and Franz Hofmeister Their Research Schools and Their Theories of Protein Structure." Proceedings of the American Philosophical Society 129 (1985) 313370. 

It is of some historical interest that Kiliani s cyanohydrin synthesis (24) enabled Emil Fischer (25) to carry out the first asymmetric synthesis. Lapworth (26) used this base-catalyzed nucleophilic 1,2-addition reaction in one of the first studies of a reaction mechanism. Bredig (27,28) appears to have been the first to use quinine (29) in this reaction as the chiral basic catalyst. More recently, others (20) have used basic polymers to catalyze the addition of cyanide to aldehydes. The structure of quinine has been known since 1908 (30). Yet it is of critical importance that Prelog s seminal work on the mechanism of this asymmetric transformation (eq. [4]) could not have begun (16) until the configuration of quinine was established in 1944 (31,32). 

Knoop. B oxidation of fatty acids. Emil Fischer, Hofmeister. Peptide structure of proteins proposed. 

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