1 BX9 [(R)-(4-fluorophenyl)-[[(2s)-2-methyl-3-sulfanyl-propanoyl]amino]methyl]boronic acid 1.000 2 BXU [(S)-(4-fluorophenyl)-[[(2s)-2-methyl-3-sulfanyl-propanoyl]amino]methyl]boronic acid 1.000 3 9DU (2r)-2-methyl-N-(phenylmethyl)-3-sulfanyl-propanamide 0.778 4 8PL (2r)-2-(4-fluorophenyl)-2-[[(2s)-2-methyl-3-sulfanyl-propanoyl]amino]ethanoic acid 0.714