Felix Hoffmann (January 21, 1868 - February 8, 1946) was a German chemist. In 1894, he joined Bayer as a research chemist. In 1897, Hoffmann, by acetylating salicylic acid with acetic acid, succeeded in creating acetylsalicylic acid (ASA) in a chemically pure and stable form. Studies found it to be a pain-relieving, fever-lowering and anti-inflammatory substance. The company developed a cost-effective production process that would facilitate the promising active ingredient to be supplied as a pharmaceutical product. In 1899 it was marketed for the first time under the trade name Aspirin. That same year he also re-synthesized diamorphine, which was popularized under the Bayer trade name of "heroin". Hoffmann moved to the pharmaceutical marketing department, where he stayed until his retirement in 1928. He never married and died in 1946 at the age of 78. No photographer credited, undated.