1 9NK (2~{R})-1-[(2~{S})-2-(phenylmethyl)-3-sulfanyl-propanoyl]piperidine-2-carboxylic acid 1.000 2 EER (2r)-1-[(2s)-2-methyl-3-sulfanyl-propanoyl]piperidine-2-carboxylic acid 0.714 3 WGV 1-(3-phenylprop-2-yn-1-yl)piperidine 0.714