1H-Imidazole-4-ethanaminium, .alpha.-carboxy-2,3-dihydro-N,N,N-trimethyl-2-thioxo-, hydroxide, inner salt, (S)- 497-30-3 Ammonium, [1-carboxy-2-(2-mercaptoimidazol-4-yl)ethyl]trimethyl-, hydroxide, inner salt, L-(+)- Ammonium, [1-carboxy-2-(2-thioxo-4-imidazolin-4-yl)ethyl]trimethyl-, hydroxide, inner salt Ergothioneine Histidine, 2-mercapto-, trimethylbetaine Histidine, 2-mercapto-N,N-dimethyl-, betaine L-Ergothioneine NSC7175 Sympectothion THIONEINE (D) Thiasine Thioeine Thiolhistidine-betaine Thioneine l-Thioneine