How was Derek H. R. Barton awarded the Noble Prize?

Name: Derek H. R. Barton. 
Country: British.
Date of Birth: 8 September 1918.
Date of Death: 16 March 1998.
The subject of Study: Aldosterone chemical reaction, chemical synthesis, conformational analysis.
Noble Prize Year: Nobel Prize for Chemistry in 1969 for their work on “conformational analysis,” the study of the three-dimensional geometric structure of complex molecules, now an essential part of organic chemistry.