(1906–87), Argentinian biochemist and Nobel laureate, known for his investigations of the processes involved in the metabolism of carbohydrates and for the discovery of sugar nucleotides, which are essential to sugar metabolism.

Born on Sept. 6, 1906, in Paris to Argentinian parents, he moved to Buenos Aires when he was two years old. In 1932 he graduated as a medical doctor from the University of Buenos Aires. After a brief period as a physician, his career was spent in research in Argentina, first at the Institute of Physiology (1932–35) and then at the Biochemical Research Institute (1947–87). He also did research for two years (1935–37) at the Biochemical Laboratory of Cambridge, England, and one year (1944) in the U.S. at Carl F. Cori’s laboratory at Washington University in Saint Louis, Mo., and at Columbia University.

Leloir"s research, started under the direction of the Argentine physiologist Bernardo Alberto Houssay (1887–1971), founder of the Institute of Physiology and a corecipient with Cori of the 1947 Nobel Prize in physiology and medicine, centered on carbohydrate metabolism, particularly the synthesis of starch and glycogen (animal starch). In 1951 he discovered and isolated glucose 1,6-diphosphate and uridine diphosphate glucose; compounds of this kind came to be called sugar nucleotides. Two other sugar nucleotides—uridine diphosphate acetylglucosamine and guanosine diphosphate mannose—were also isolated. His work on dolichol (an alcohol found in tobacco), aldehydes, and other substances laid the foundation for the modern study of the biosynthesis of polysaccharides (carbohydrates such as cellulose, dextrin, starch, and glycogen).

In 1970 Leloir was awarded the Nobel Prize in chemistry for “his discovery of sugar nucleotides and their role in the biosynthesis of carbohydrates.”

Leloir died on Dec. 2, 1987, in Buenos Aires.