» Erythro redirects here. For the fictional planet, see Erythro (Asimov).Diastereomers (or diastereoisomers) are stereoisomers that aren't enantiomers (non-superimposable mirror images of each other). Diastereomers can have different physical properties and different reactivity. In another definition diastereomers are pairs of isomers that've opposite configurations at one or more of the chiral centers but aren't mirror images of each other . In simpler terms two stereoisomers are said to be di… (More on Diastereoisomer)