(3R)-3-hydroxy-D-aspartic acid(2R,3R)-2-amino-3-hydroxybutanedioic acid(2R,3R)-2-amino-3-hydroxysuccinic acid(R,R)-3-hydroxyaspartic acidD-threo-3-hydroxyaspartic acidD-threo-beta-hydroxyaspartic acidthreo-3-hydroxy-D-aspartic acidthreo-D-3-hydroxyaspartic acidthreo-beta-hydroxy-D-aspartic acid