Three salts from the reactions of cysteamine and cystamine withL-(+)-tartaric acid

Reaction between cysteamine (systematic name: 2-aminoethanethiol, C 2 H 7 NS) and L-(+)-tartaric acid [systematic name: (2 R ,3 R )-2,3-dihydroxybutanedioic acid, C 4 H 6 O 6 ] results in a mixture of cysteamine tartrate(1−) monohydrate, C 2 H 8 NS + ·C 4 H 5 O 6 − ·H 2 O, (I), and cystamine bis[tartrate(1−)] dihydrate, C 4 H 14 N 2 S 2 2+ ·2C 4 H 5 O 6 − ·2H 2 O, (III). Cystamine [systematic name: 2,2′-dithiobis(ethylamine), C 4 H 12 N 2 S 2 ], reacts with L-(+)-tartaric acid to produce a mixture of cystamine tartrate(2−), C 4 H 14 N 2 S 2 2+ ·C 4 H 4 O 6 2− , (II), and (III). In each crystal structure, the anions are linked by O—H...O hydrogen bonds that run parallel to the a axis. In addition, hydrogen bonding involving protonated amino groups in all three salts, and water molecules in (I) and (III), leads to extensive three-dimensional hydrogen-bonding networks. All three salts crystallize in the orthorhombic space group P 2 1 2 1 2 1 .