Ehrlich and Hata. Portrait of Paul Ehrlich (1854- 1915) and Sahachiro Hata (1873-1938), the bacter- iologists from Germany and Japan respectively who discovered the first cure for syphilis. From 1896 Ehrlich (left) tried to find a chemical that comb- atted the Trypanosoma parasites that caused sleep- ing sickness. By 1907 he tried his 606th compound, dihydoxydiamino-arsenobenzene, but found it ineff- ective. In 1909 Hata, a new student of Ehrlich's, was practising in the use of arsenic compounds when he found that compound 606 was effective against the syphilis bacillus Treponema pallidium. Ehrlich, who had tried over 900 chemicals, named compound 606 salvarsan (now called arsphenamine).