The Nobel Prize in Chemistry 1937 was divided equally between Walter Norman Haworth "for his investigations on carbohydrates and vitamin C" and Paul Karrer "for his investigations on carotenoids, flavins and vitamins A and B2".
 

Ever since it became clear that vitamins in food play an essential role in maintaining health and preventing diseases, these nutrients found themselves the subject of intense scrutiny by scientists eager to identify the active components and their chemical make-up. Haworth and his colleague Edmund Hirst successfully synthesised vitamin C in the laboratory, making this the first vitamin to be artificially produced. Their breakthrough made it possible for vitamin C, or ascorbic acid as Howarth called it, to be produced cheaply on a large scale for medicinal use. Paul Karrer's entry into the field of vitamins came through his research on the chemistry of carotenoids, a family of orange-yellow plant pigments that are related to the pigment in carrots. Karrer also helped to illuminate our knowledge of another vitamin by deriving the chemical structure of factoflavin.