MARCHLEWSKI, Leon Paweł

From 1888 to 1890, M. studied at the Swiss Technical College in Zürich. As an assistant to Professor of Chemical Technology, Jerzy Lunge, together they succeeded in developing an improved method of the analysis of the mixture of sulphur oxide in the extraction of sulphuric acid, as well as nitrate gases in the extraction of nitrous acid. The result of their work is known as the »Lunge-M.-Aparat« gas meter. In 1892, he received his doctorate with the work A Critical Study on the Methods of Determining Sulphuric Sulphide (Kritisches Studium über Methoden der Bestimmung des Sulfidschwefels). He left Zürich the same year and began working as an assistant for organic chemistry at the private laboratory of Edward Schunck in Kersal near Manchester. M. was engaged in organic and physiologic chemistry, particularly in natural glycosides – sugar compounds. He unravelled the chemical structure of Rubian, a component of one of the glycosides in the indigo plant or dyer's woad, determining the chemical formula of the so-called plant indicant, from which the blue indigo pigment is obtained. In 1897, M. became head of the laboratory of the „Claus und Ree“ dyestuffs and pharmaceutical factory in Clayton near Manchester, and began lecturing organic chemistry at the Institute of Technology in Manchester. In 1900, he took over the management of the Food Research Centre in Krakow, where he continued his research into compounds connected with indigo - indirubin and isatin – and discovered a new chemical compound, which he named indofezanin. In his scientific and research work, he also studied the compounds of the green plant pigment chlorophyll, and the compounds of the blue pigment haemoglobin. With the aid of spectral photometry, he researched the absorption spectrum of phylloporphyrines and haematoporphyrines, discovering that they are almost identical. In the case of the empirical formula of phylloporphyrines, only a single atom was missing.
On the basis of his observations, he proposed a thesis that phylloporphyrin and haematoporphyrin are linked compounds, from which he drew connections between the parent substances of these compounds.
He published a summary of his research in 1893, in the monograph The Chemistry of Chlorophyll (Die Chemie des Chlorophyl). That very year he was appointed associate professor by the Jagiellonian University in Krakow, and in 1906 full professor of chemistry. Simultaneously, as head of the Department of Medicinal Chemistry, he also lectured at the Faculty of Medicine from 1918 until 1939, as full professor.
M. was a member of the Academy of Sciences in Krakow, and in 1938 the chairman of the Polish Academy of Sciences. He was elected chancellor of the Jagiellonian University twice (in 1926 and 1928). As the only Pole, M. was elected to the „Societé de Chimie de France” as an honorary member. He was also a corresponding member of the Yugoslav Academy of Sciences, the Czechoslovak Academy of Agriculture, the Romanian Chemical Society, and between 1930 and 1935 a senator of the Republic of Poland.