![]() ![]() Independently, ascorbic acid was synthetized in 1933 by Tadeusz Reichstein (the Nobel Prize laureate in Physiology or Medicine in 1950). Because of their work, in 1937 two Nobel Prizes: in Chemistry and in Physiology or Medicine were awarded to Haworth and Szent-Györgyi, respectively. In reference to the compound's antiscorbutic properties, Haworth and Szent-Györgyi proposed to rename it "a-scorbic acid" for the compound, and later specifically l-ascorbic acid. In 1933, sugar chemist Walter Norman Haworth, working with samples of "hexuronic acid" that Szent-Györgyi had isolated from paprika and sent him in the previous year, deduced the correct structure and optical-isomeric nature of the compound, and in 1934 reported its first synthesis. In 1932 Charles Glen King confirmed that it was indeed the antiscorbutic factor. ![]() Between 19, Albert Szent-Györgyi isolated a candidate for this substance, which he called it "hexuronic acid", first from plants and later from animal adrenal glands. In 1907, Axel Holst and Theodor Frølich discovered that the antiscorbutic factor was a water-soluble chemical substance, distinct from the one that prevented beriberi. ![]() The antiscorbutic properties of certain foods were demonstrated in the 18th century by James Lind. The " d" form can be made via chemical synthesis but has no significant biological role. It is used as a food additive and a dietary supplement for its antioxidant properties. Deficiency of vitamin C causes scurvy, formerly a major disease of sailors in long sea voyages. The l isomer is the one most often encountered: it occurs naturally in many foods, and is one form (" vitamer") of vitamin C, an essential nutrient for humans and many animals. It is a mild reducing agent.Īscorbic acid exists as two enantiomers (mirror-image isomers), commonly denoted " l" (for "levo") and " d" (for "dextro"). It dissolves well in water to give mildly acidic solutions. It is a white solid, but impure samples can appear yellowish. Ascorbic acid is an organic compound with formula CĦ, originally called hexuronic acid. ![]()
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