William Klyne (March 23, 1913, in Enfield, Middlesex – November 13, 1977) was an organic chemist known for his work in steroids and stereochemistry — a field in which he was a "pioneer",^[1] and in which Ernest Eliel and Norman Allinger described him as "one of the world's experts".^[2]

In 1946, he gained a PhD from the University of Edinburgh with a thesis entitled “The steroid sulphates: studies on the conjugated sulphates of mare’s pregnancy urine".^[3]

Klyne taught at Westfield College, University of London, where he served as dean of science from 1971 to 1973, and as vice-principal from 1973 to 1976.^[4] He also served on the editorial board of the Biochemical Society from 1950 to 1955,^[4] and on IUPAC's nomenclature committee from 1971 until his death.^[4] As well, he established^[5] and maintained^[4] the Medical Research Council's Steroid Reference Collection, and wrote several textbooks, including The Chemistry of Steroids (1957) and Atlas of Stereochemical Correlations (1974).^[6]

Klyne met Barbara Clayton in 1947 while both were employed at the Medical Research Council; they married in 1949.^[7]

• Klyne–Prelog system
• Ultraviolet–visible spectroscopy of stereoisomers