Emil Fischer
Hermann Emil Fischer, born 1852, discovered a family of bases called purines. Caffeine and theobromine—found in tea, coffee, and chocolate—are two familiar purines. Fischer received a Nobel Prize in 1902.
Credit: the Nobel Foundation
Early in his career Fischer discovered a family of bases called purines. Caffeine and theobromine—found in tea, coffee, and chocolate—are two familiar purines. Other purines that he discovered later are important building blocks of DNA. Fischer also studied sugars and their structures. In both his work on purines and on sugars, he was very dedicated in studying the reaction and degradation products of the compound in question. From this information he proposed an appropriate molecular structure. Then he attempted to synthesize such a compound in order to prove, or disprove, his proposal.
Fischer soon realized that many sugars were spatial isomers and could be differentiated by using Jacobus Henricus van’t Hoff’s theory of the tetrahedral carbon atom. In order to depict such isomers on a page, he developed the “Fischer projection” method, wherein horizontal lines represent bonds projecting from the plane of the paper toward the viewer, and vertical lines represent bonds projecting away from the viewer. His study of sugars led him to study their fermentation and the enzymes that cause it. In the course of this research he famously noted that the action of an enzyme is highly specific: “To make use of an image, I shall say that enzyme and glucoside [the natural precursor of glucose] must fit together like lock and key.” For his work on purines and sugars, he was awarded the 1902 Nobel Prize in chemistry.
Visit Chemistry in History to learn more about Emil Fischer’s work.
Excerpted with permission, Chemical Heritage Foundation
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