(1887-1976) Swiss chemist who began research on natural compounds such as musk and civet secretions. In the 1930s he investigated sex hormones, and in 1934 succeeded in extracting the male hormone androsterone from 31,815 liters/7,000 gallons of urine and synthesizing it. Born in Croatia, Ruzicka settled in Switzerland in 1929. Ruzicka shared the 1939 Nobel Prize for Chemistry with Adolf Butenandt.