FISCHER, HANS

(b Höchst am Main, Germany, 27 July 1881; d. Munich, Germany, 31t March 1945)

chemistry.

Fischer’s father, Eugen, was a dye chemist in the large dye works of Mister. Lucius, and Bruning in Höchst; and while the boy was still young, the father became director of the laboratory of the Kalle Dye Works in Biebrich, near Wiesbaden. Young Fischer thus was early acquainted with the chemistry of pigments. He began the study of medicine and chemistry at Marburg, where, under the influence of Theodor Zincke, he decided to specialize in chemistry. After graduating in 1904 he continued his medical studies at Munich and spent a year in Berlin as assistant to Emil Fischer (no relation), working on peptides and sugars.

In 1910 Fischer went to a medical clinic in Munich, where he began to study the constitution of the bile pigment bilirubin; and his Habilitationsschrift (1912) was based on these studies. He accepted the chair of medical chemistry at the University of Innsbruck, as successor to Adolf Windaus, in 1916: and two years later he assumed a similar position in Vienna. During World War I and the reconstruction period that followed, he was unable to carry on any continuous research. In 1921. however. Fischer became head of the Institute of Organic Chemistry at the Technische Hochschule of Munich, succeeding Heinrich Wieland. He remained there for the rest of his life, and it was there that he conducted his most important studies.

In 1935 Fischer married Wiltrud Haufe, who was thirty years younger than he. It was a happy marriage. Although he suffered from tuberculosis at the age of twenty and had had a kidney removed in 1917, he was active in mountaineering and skiing and enjoyed long automobile trips. During World War II, Fischer became severely depressed, especially when his institute was almost totally destroyed by bombing. Convinced that his lifework had been shattered, he committed suicide in March 1945.

When Fischer began his research in Munich, he continued his earlier work on bile pigments and related substances. The general outlines of porphyrin chemistry were known, and in 1912 W. Küster had proposed a formula for the porphyrin ring that was essentially correct. It was Fischer’s task to establish the accuracy of the earlier work and to carry it to its logical conclusion. He recognized that the significant feature of bilirubin was its content of four pyrrole rings and that the pigment itself was a degradation product of he in, the active portion of the hemoglobin molecule. In addition, he soon learned that in the pathological condition known as porphyria, several other porphyrin ring compounds were excreted, including coproporphyria and uroporphyrin . Other porphyrins were found in a wide variety of natural sources. Chlorophyll, the green pigment of leaves, was also a porphyrin, differing from hem in in its content of magnesium instead of iron. Fischer found that the various porphyrins were distinguished from one another chiefly by the presence of differing substi-tuents on the pyrrole rings.

He therefore began a systematic study of a number of synthetic pyrrole derivatives and became an authority on pyrrole chemistry, writing the definitive monograph on this subject (1934-1940). While working on the syntheses of various porphyries, Fischer developed microana-lytical techniques so successfully that more than 60,000 microanalyses were carried out in his laboratory. He found reactions by which two pyrrole rings could be combined into dipyrrylmethenes. which in turn could be combined to form porphyrin rings. In 1926 he carried out the first synthesis of a porphyrin, and in 1929 he was able to prepare hem in. For the latter achievement he received the 1930 Nobel Prize in chemistry. It was only later that Fischer finally determined the structure of bilirubin, the compound with which he had begun his research. Since hem in was closely related to chlorophyll, he next studied the plant pigment. He identified the pyrrole rings of chlorophyll but died before completing its synthesis, which was accomplished in 1960 at Munich and, independently, at Harvard.

The author of over 300 papers, Fischer also received the Davy Medal of the Royal Society and an honorary doctorate from Harvard.

BIBLIOGRAPHY

I. Original Works. Fischer’s chief book is Die Chemise des Pyrrols 3 vols. (Leipzig. 1934- 1940), written with Hans Orth. An extensive review of his own work is “Hemin und Porphyrine” in Verhandhlungen der Deutsche Gcsellschaft für inner Medizin45 (1933). 7-27.

II. Secondary Literature. Fischer’s scientific work is reviewed by F. Baumgärtel. “Zur Erforschung der Blut- und Gallenfarbstoffe. Hans Fischer zum Gedächtnis.” inMedizinische Klinik.42 (1947), 3 1 - 34. Biographical details are given by Karl Keile, “Das Lebenswerk Hans Fischers,” in Naturwissenschaften,33 (1946), 289-291; H. Wieland, “Hans Fischer und Otto Hönigschmid zum Gedächtnis,” in Angewandte Chemise,62 (1950). 1-4-the portion relating to Fischer has been translated by Ralph Oesper in E. Farber, ed.. Great Chemists (New York, 1961), 1527-1533: and Alfred Treibs. “Hans Fischer, 1881-1945.” in Chemise in unsererZeit.1 (1967), 58-61.

Henry M. Leicester