Fisher, Emile

Prior to 1890, formaldehyde was not commercially available [2]. Thus the first phenol-formaldehyde resins were made using formaldehyde equivalents such as methylene diacetate or methylal [2,20]. The first true phenol-formaldehyde resin was made by Kleeberg at the direction of Emil Fisher in 1891 [2,21]. Saliginen (o-hydroxymethyl phenol) was recognized as a condensation product of phenol and formaldehyde in 1894 and was the subject of United States patents in 1894 and 1896 [22,23]. 

In 1896, Emil Fisher found that 2,5-diphenyloxazole hydrochloride was precipitated by passing gaseous hydrogen chloride into an absolute ether solution of benzaldehyde and benzaldehyde cyanohydrin. The oxazole hydrochloride can be converted to the free base by addition of water or by boiling with alcohol. Many different aromatic aldehydes and cyanohydrin combinations have been converted to 2,5-diaryloxazoles 4 by this procedure in 80% yield. ... 

Dynamic combinatorial chemistry (DCC) is founded on the study and the construction of mixtures of discrete constituents which are produced by reversible molecular or supramolecular associations [1, 2], The composition of a dynamic combinatorial library (DCL) is thermodynamically driven and, as such, is able to adapt itself to any parameter that - permanently or transiently - modifies its constitution/energy potential surface [3,4], Thus, in the presence of various internal or external parameters, the involved equilibria can be displaced toward the amplification of given products through an adaptation process that will occur through an in situ screening of these species. A schematic representation using Emil Fisher lock-and-key metaphora can be used to illustrate these concepts (Fig. 1). 

R. U. lemieux and U. Spohr, How Emil Fisher was led to the lock and key concept for enzyme specificity, Tldv. Carbohydr. Chem Biochem. 50 1(1994). 

However, if the current attitudes persist and most scientists are not educated in the peptide sciences, and do not know how to design, synthesize, and evaluate peptides and peptidomimetics with desirable chemical and biological properties, the current ignorance and prejudice will become a self-fulfilling prophecy. Considering that Emil Fisher, perhaps the greatest organic chemist, was the father of peptide and protein chemistry, and that two peptide hormones, insulin and oxyto-... 

To date, the latex of Carica papaya L. is known to contain at least four different proteolytic enzymes, namely, papain (E.C. 3.4.22.2), chymopapain (E.C. 3.4.22.6), caricain or papaya proteinase III or 2 (E.C. 3.4.22.30), and glycyl endopeptidase or papaya proteinase IV (E.C. 3.4.22.25). The importance of the latex of the unripe fruit of the tropical tree Carica papaya L. was first noted by G. C. Roy, who in 1873 published in the Calcutta Medical Journal (see Ref. 1) an article entitled The solvent action of papaya juice on the nitrogenous articles of food. The name papain was used for the first time by Wurtz and Bouchet [2] to describe partially purified cysteine proteinases from the papaya latex. They wrote, nous designerons ce ferment sous le nom de papa ine." In 1880, Wurtz postulated that papain acts in fibrin digestion by becoming bound to the fibrin [3]. This is remarkable in that Emil Fisher first described the specific association of enzyme with substrate in 1898. Since that time, many names have been used for commercial latex products, e.g., papayotin, papaoid, etc. 

The importance of insulin made it the focus of Frederick Sanger s work in structural chemistry. Sanger applied chemist Emil Fisher s philosophy, using chemical principles to explicate protein structure and function. Sanger eventually established the order of amino acids that made up insulin, the first protein for which the amino acid sequence was determined. Knowing the sequence enabled comparison between insulins from different species, and discovery of the slight differences between them. 

Molecular properties, whose variations can be attributed to variations in molecular sh, include odor, taste, optical dichroism (the octant rule ), chirality, and drug-receptor interaction. In 1920 RuiiCka forwarded a theory that the character of an odoriferous substance is determined by its molecular shape, while the variations of this character depend on the osmophoric groups in a molecule. This presented but one illustration of Emil Fisher s lock and key model for interaction of drugs and enzymes. ... 

When the binding of a ligand to its receptor is considered, many of us instinctively think of the century-old lock and key model first proposed by Emil Fisher." As shown in Figure 7.10(a), here the shape of the ligand is complementary to the binding site of a receptor so that a fixed conformation of each simply comes together to form the complex. 

The possibility that an enzyme could be assembled entirely by chemical methods is not new and was first raised by Emil Fischer in a note to his contemporary Adolf Bayer in 1905 My entire yearning is directed toward the first synthetic enzyme. If its preparation falls into my lap with the synthesis of a natural protein material, 1 will consider my mission fulfilled. [199]. While Fisher made important contributions to peptide chemistry culminating in the synthesis of an 18-mer peptide [4], his dream of enzyme total synthesis went unfulfilled in his lifetime. The synthetic and analytical technologies required to accomphsh this ambitious goal would take decades to develop [58]. 

Lichtenthaler, F.W. 100 years " Schliissel-Schloss-Prin-zip" What made Emil Fisher use this analogy Angew. Chem.. Int. Ed. Engl. 1994. 33 (23 24). 2364-2374. 

Until relatively recently, interest in chiral chemistry has been largely academic and, as a consequence, has occupied a relatively minor position in the analytical chemistry syllabuses of most universities. Despite the emphasis that has been placed on the recent advances in chiral chemistry, optical isomers have been know for many years and were first identified by Biot [1] in the early 1800s, and their existence was established by the work of Pasteur [2] in 1848. Both van t Hoff [3] and Le Bel [4] proposed the existence of the asymmetric carbon atom and used it to explain the cause of optical rotation. However, it was Emil Fisher [5], who made the first serious attempts to relate the absolute stereochemistry of optical isomers and determined the configuration of (+)-glucose for which he received the Nobel prize. Fisher predicted that the (+)-isomer of glyceraldehyde was the D-isomer and arbitrarily assigned the stereochemistry as ... 

Fischer, Emil, 1852-1919 (p. 24, Plate 1), son of a merchant was born in 1852 in Euskirchen (Rhineland) studied chemistry in Bonn (Kekule), StraBburg (A. Baeyer, physics A. Kundt) where he graduated Dr. phil. in 1874. Assistant with Baeyer, from 1874 in Munich. Professor in Erlangen (1882-1885), then in Wurzburg until his call to the famous Chemical Institute of the University of Berlin as successor to A.W.v. Hofmann, in 1892. Amino acid and peptide research from 1900, after extremely successful research in the field of carbohydrates and purines. Fisher died in the summer of 1919 in Berlin. He was the second winner of the Nobel Prize for Chemistry in 1902, after van t Hoff in 1901. 

The importance of molecular stereochemistry for biological activity was recognized 100 years ago, by Emil Fisher, with his lock and key theory for enzymatic reactions (Motoc 1983). The steric fit of dmg molecule (L-ligand) with its target (usually, receptor, R) depends upon both the shape of the biological receptor and the shape of ligand molecule. MTD (minimal topological difference) method takes into... 

The names of many great chemists are associated with the study of proteins. The famous organic chemist Baron Justus von Liebig maintained for a long time that all proteins stemmed from only one type of molecule, and all variations had the same radical. But the composition of these large molecules was to remain mysterious until Emil Fisher established that proteins were made of up to 20 different amino acid residues linked by polypeptide bonds. 

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