In 1933, working in Zürich, Switzerland, Reichstein succeeded, independently of Sir Norman Haworth and his collaborators in Britain, in synthesising vitamin C (ascorbic acid).
Together with E. C. Kendall and P. S. Hench, he was awarded the Nobel Prize for Physiology and Medicine in 1950 for their work on hormones of the adrenal cortex which culminated in the isolation of cortisone.
The principal industrial process for the artificial synthesis of Vitamin C still bears his name.