Arthur Rudolf Hantzsch (1857-1935)

German chemist born in Dresden, professor in Zurich, Würzburg and Leipzig. In 1881 he described the synthesis of pyridines from β-keto esters, aldehydes and ammonia, and later the thiazole and pyrrole syntheses that also bear his name.

With Alfred Werner he proposed in 1890 the geometrical isomerism of oximes, based on the geometry of nitrogen. He also studied the structure of diazonium compounds and the chemistry of strong acids.

More information: en.wikipedia.org