History of aspirin mid-eighteenth century. By the nineteenth century pharmacists were experimenting with and prescribing a variety of chemicals related to salicylic acid, the active component of willow extract. In 1853, chemist Charles Frédéric Gerhardt treated acetyl chloride with sodium salicylate to produce acetylsalicylic acid for the first time; in the second half of the nineteenth century, other academic chemists established the compound's chemical structure and devised more efficient methods of synthesis. In 1897, scientists at the drug and dye firm Bayer began investigating acetylsalicylic acid as a less-irritating replacement for standard common salicylate medicines, and identified a new way to synthesize it.
Bisdehydrodoisynolic acid Bisdehydrodoisynolic acid Bisdehydrodoisynolic acid (BDDA), as the (Z)-isomer ((Z)-BDDA), is a synthetic, nonsteroidal estrogen related to doisynolic acid that was never marketed. It is one of the most potent estrogens known, although it has more recently been characterized as a selective estrogen receptor modulator (SERM). BDDA and other doisynolic acid derivatives display relatively low affinity accompanied by disproportionately high estrogenic potency "in vivo", which was eventually determined to be due to transformation into metabolites with greater estrogenic activity. The drug was discovered in 1947 as a degradation product of the reaction of equilenin or dihydroequilenin with potassium hydroxide. It is