. . . . . "2-Amino-3-[3-[(2-amino-3-hydroxy-3-oxopropyl)thio]-4,5-dihydroxyphenyl]propanoic acid" . . . . . . . "cysteinyldopa" . . "5-S-Cysteinyldopa" . . . . . . "Cysteinyldopa" . . "Cysteinyldopa" . .