Jeanette Grasselli Brown born 1928: vibrational spectroscopy; edited Atlas of Spectral Data and Physical Constants for Organic Compounds; Garvan Medal, 1985
Felix Hoffmann of Bayer made a stable derivative of salicylic acid in 1897. This pain-reliever had fewer side effects than the parent acid, and is now known as aspirin.
Nikolai Nikolaevich Zinin born 1812: founding president of the Russian Chemical Society (now the Mendeleev Russian Chemical Society); reduction of aromatic nitro compounds to amines; benzidine rearrangement.