1 PEC S,S-pentylthiocysteine 1.000 2 BUC S,S-butylthiocysteine 0.923 3 C1S 3-(prop-2-en-1-yldisulfanyl)-L-alanine 0.846 4 PR3 S,S-propylthiocysteine 0.769 5 SCS 3-(ethyldisulfanyl)-L-alanine 0.769 6 6WK (2~{R})-2-azanyl-3-[[(2~{S},3~{S})-2,3-bis(oxidanyl)-4-sulfanyl-butyl]disulfanyl]propanoic acid 0.750 7 0QL 3-[(2-aminoethyl)disulfanyl]-L-alanine 0.714 8 CME S,S-(2-hydroxyethyl)thiocysteine 0.714 9 EFC S,S-(2-fluoroethyl)thiocysteine 0.714