In 1876, Methylene blue, a derivative of phenothiazine, was first synthesized by Heinrich Caro at BASF and the structure was determined in 1885 by Heinrich August Bernthsen.
In 1876, methylene blue, a derivative of phenothiazine, was synthesized by Heinrich Caro at BASF. The structure was deduced in 1885 by Heinrich August Bernthsen.