| 1 | 2,3-dihydroxy-1,4-dithiobutane |
| 2 | (2r,3r)-1,4-disulfanylbutane-2,3-diol |
| 3 | L-dtt |
| 4 | L-threo-1,4-dimercapto-2,3-butanediol |
| 5 | (2r,3r)-1,4-dimercaptobutane-2,3-diol |
| 6 | L-dithiothreitol |
| 7 | 1,4-dithiothreitol |
| 8 | Dl-threo-1,4-dimercapto-2,3-butanediol |
| 9 | Threo-1,4-dimercapto-2,3-butanediol |