Alitame [l-α-aspartyl-N-(2,2,4,4-tetramethyl-3-thioethanyl)-d-alaninamide] is an amino acid-based sweetener developed by Pfizer Central Research from l-aspartic acid, d-alanine, and 2,2,4,4-tetraethylthioethanyl amine. A terminal amide group instead of the methyl ester constituent of aspartame was used to improve the hydrolytic stability. The incorporation of d-alanine as a second amino acid in place of l-phenylalanine has resulted in optimum sweetness. The increased steric and lipophilic bulk on a small ring with a sulfur derivative has provided a very sweet product and good taste qualities. Alitame is noncariogenic. From an oral intake, 7–22% is unabsorbed and excreted in the feces. The remainder is hydrolyzed to aspartic acid and alanine amide. The aspartic acid is normally metabolized, and the alanine amide is excreted in the urine as a sulfoxide isomer, sulfone, or conjugated with glucuronic acid. U.S. Food and Drug Administration has approved alitame for use as per acceptable daily intake (ADI) value.