(2S,3S,4S,5R)-2-(hydroxymethyl)-5-methylpyrrolidine-3,4-diol
(2S,3S,4S,5R)-2-(hydroxymethyl)-5-methyl-pyrrolidine-3,4-diol
(2R,3S,4S,5S)-2-methyl-5-methylol-pyrrolidine-3,4-diol