Fischer, Emil natural products

The natural substrate for the dehydrogenase, glyceraldehyde-3-phosphate (G-3-P), had been synthesized earlier by Hermann Fischer, Emil Fischer s son, and Baer in 1932. In 1934 Meyerhof and Lohmann synthesized hexose diphosphate, establishing it to be fructose 1,6 bisphosphate (F-l, 6 bis P). With F-1,6 bisP as substrate and hydrazine to trap the aldehydic and ketonic products of the reaction, G-3-P was identified in the mixture of G-3-P and dihydroxyacetone phosphate which resulted. Triose phosphate isomerase was then isolated and the importance of phosphorylated 3C derivatives established. 

Carbohydrates and polysaccharides, on the one hand, and peptides and proteins, on the other, have been considered as separate classes of natural products for a long time. Fundamental chemical methodology for the synthesis of both saccharides and peptides was developed by Emil Fischer et al. at the beginning of the 20th century. 1,2 However, the harsh conditions employed in early solution and solid-phase peptide synthesis hindered the combination of peptide and carbohydrate chemistry, i.e. glycopeptide synthesis. Considerable efforts were made to combine the two branches of natural product chemistry, and the state of the art within glycopeptide synthesis has improved dramatically during the last decades, as described in a number of reviews. 3 23,512"514 ... 

Although students were not yet declaring themselves biochemists (the term biochemistry did not appear until around 1910), the study of natural products—their formation and function in nature— has always been part of the investigation of materials. In the last decades of the 1800s, chemists made considerable progress in identifying the structures and properties of many important natural products. The leader in this field was Baeyer s student Emil Fischer. 

The first Nobel laureate in chemistry (1901) was Jacobus van t Hoff, the veterinarian who visualized three-dimensional carbon. The second Nobel Prize went to Emil Fischer, the guru of natural product identification. The prize was the validation of his work, but not of his life. When three of his four sons were killed in World War I, he committed suicide. 

The evidence that in natural products, especially in primary metabolites, some structural patterns are repeated in different structures, implies that most organisms have common biosynthetic pathways. At the end of the nineteenth century when the biosynthetic pathways were not known, Heinrich Kiliani and Hermann Emil Fischer developed a simple model which could explain how stereochemically pure long-chained monosaccharides can form from simple molecules. The simplest, parent monosaccharide is aldotriose with only one chiral carbon atom. Hence, there are D- and L-aldotrioses. Since aldotriose is the product of mild oxidation of glycerol it can also be called glyceraldehyde. 

Emil Fischer (1852-1919), who devised these formulas, was one of the early giants in the field of organic chemistry. He did much to elucidate the structures of carbohydrates, proteins, and other natural products and received the 1902 Nobel Prize in chemistry. 

Natural product chemistry has continued to make rapid advances, although no individual has made a contribution to rival that of Emil Fischer. Carbohydrate chemists have concentrated on molecules in which individual sugar molecules are linked together, and have now solved the structures of many oligo- and polysaccharides. Other classes of compound which have been studied include the steroids and terpenes. Extensive work has also been done on groups such as the vitamins and the hormones, in which the individual members belong to different chemical classes. 

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