Leopold Ruzicka Nobel Prize in Chemistry, 1939 (together with A. Butenandt). Date of Birth: 13.09.1887 Country: Switzerland

Biography of Leopold Ruzicka

Leopold Ruzicka was a Swiss organic chemist who was awarded the Nobel Prize in Chemistry in 1939. He was born in Vukovar, Austria-Hungary (now Serbia) and was the eldest of two sons of a cooper, Stpan Ruzicka, and Lubica Sever. After his father's death in 1891, Ruzicka and his mother and brother moved to Osijek, where he completed his secondary education. Ruzicka initially planned to work at a newly constructed sugar factory in Osijek, but he decided to pursue his education in Germany due to the unrest in the Austro-Hungarian Empire. In 1906, he enrolled at the Technical University in Karlsruhe. He completed his higher education in record time, receiving both an engineering degree and a doctoral degree in 1910. His doctoral research focused on the reactivity of ketenes and was supervised by Georg Staudinger, who later won the Nobel Prize in Chemistry in 1953. After completing his studies, Ruzicka began working as Staudinger's assistant. In 1912, Staudinger was appointed director of the Federal Institute of Technology in Zurich, and Ruzicka followed him there. For four years, Ruzicka assisted Staudinger in researching insecticides produced by the plant Chrysanthemum cinerariefolium. However, Ruzicka became more interested in the chemistry of natural substances and in 1916, he informed Staudinger of his decision to pursue independent research. Staudinger withdrew his support, but Ruzicka obtained Swiss citizenship in 1917. In the same year, the German perfume company "Haarmann & Reimer" provided him with a loan to develop a method for synthesizing irone, an aromatic substance with a violet-like scent. Around the same time, he became a lecturer at the Federal Institute of Technology, which granted him access to its laboratories. From 1918 to 1921, Ruzicka conducted research for the Swiss chemical company "Ciba AG," and in 1920, he became a lecturer at the University of Zurich. From 1920 to 1924, he synthesized alicyclic ketones with ring sizes ranging from 8 to 34. He also studied natural alicyclic derivatives and developed a method for determining the carbon skeleton of sesquiterpenes found in certain plant oils. In 1923, Ruzicka was elected professor at the Federal Institute of Technology, but he did not receive a salary there. As a result, he began working in the laboratory of a perfume factory in Geneva in 1926. In 1930, he determined the structure of santonin, a well-known anthelmintic agent. He also identified the structures of other natural alicyclic derivatives, such as cyclopentadecanone, isolated from chamomile, and muscone, and synthesized cybetone. He discovered that irone, previously thought to be a single compound, was actually a mixture of several ketones. In 1926, Ruzicka became a professor of organic chemistry at the University of Utrecht and worked there until 1929 when he returned to Zurich as the director of the Federal Institute of Technology, succeeding R. Cuno. Ruzicka began investigating the structure of complex terpenes and other related hydrocarbons in the 1930s. By 1934, he had partially synthesized the male hormones androsterone and testosterone, determining the structure of testosterone in the following year. In 1935, Ruzicka and Adolf Butenandt independently synthesized testosterone and discovered that the presence of a double bond between the 4th and 5th carbon atoms in the sterane nucleus determined the androgenic activity of male sex hormones, while a double bond between the 1st and 2nd carbon atoms resulted in estrogenic activity. Ruzicka was nominated for the Nobel Prize from 1931 onwards, and in 1939, he shared the Nobel Prize with Butenandt for their work on polymethylenes and higher terpenes. Due to World War II, Ruzicka received his prize from the Swedish ambassador, Baron Hans G. Beck-Friis, at a special ceremony held on January 16, 1940, at the Federal Institute of Technology in Zurich. He delivered his Nobel lecture in Stockholm five years later, on December 12, 1945. Ruzicka's research on the structure, properties, and synthesis of sex hormones paved the way for the study of the role of the adrenal cortex, which secretes hormones that regulate water and electrolyte balance, as well as carbohydrate and protein metabolism in the body. From the mid-1930s, Swiss chemist Tadeus Reichstein and his colleagues isolated dozens of corticosteroid hormones from adrenal cortex extracts, named corticosteroids according to their source. The structure of these hormones was subsequently determined, and their physiological role and mechanism of action were investigated. In 1950, Edward Calvin Kendall, Reichstein, and Philip Showalter Hench were awarded the Nobel Prize in Physiology or Medicine for their work in this field. Another important challenge was the synthesis of corticosteroids. The complete synthesis of one of them, cortisol, required 20 years of effort by Robert Woodward, who won the Nobel Prize in Chemistry in 1965. Despite its extremely low yield (1.7 x 10^-8 %), it was considered one of the greatest triumphs of synthetic organic chemistry. During the war years, Ruzicka helped several Jewish scientists escape from Nazi-occupied Europe and provided refuge for others. He actively supported the Yugoslav resistance movement and founded the Swiss-Yugoslav Society to aid war victims during and after the war. In the post-war years, Ruzicka dedicated much of his time to collecting art, with a preference for works by Dutch and Flemish masters from the 17th century. He later donated his collection to the Zurich Museum of Art. Despite being severely colorblind, especially in distinguishing red, Ruzicka pursued color photography as a hobby. After retiring from the Federal Institute of Technology in 1957, Ruzicka continued to work as a consultant for various chemical companies. In his retirement, he became an avid gardener, particularly enjoying cultivating roses and alpine flowers. He considered himself to juggle three professions - chemist, gardener, and art connoisseur - and devoted himself fully to each of them. Ruzicka was known for his strong character and being an energetic and inspiring individual. His sincerity and directness often shocked those who interacted with him, and sometimes they even felt offended. However, he was willing to accept criticism if it was well-argued. He was not a skilled lecturer, and the few attendees of his lectures were drawn to the humor and inventiveness of his assistant.