Synonyms: Hydroxy-L-proline;(2S,4R)-4-hydroxypyrrolidine-2-carboxylic acid;trans-4-Hydroxyproline;L-Proline, 4-hydroxy-, trans-;Hypro;4-Hydroxy-L-proline;trans-4-Hydroxy-L-proline;(2R,4R)-4-hydroxy-2,3,4,5-tetrahydropyrrole-2-carboxylate;(2R,4S)-4-hydroxypyrrolidine-2-carboxylic acid;Proline, 4-hydroxy-, L-;