Abstract
Stereoisograms proposed for reexamining the relationships between stereoisomers (RS-stereoisomers) contain three relationships (enantiomeric, RS-diastereomeric, and holantimeric relationships), which correspond to three attributes (chirality, RS-stereogenicity, and sclerality). The three relationships are correlated to three relationships for describing internal structures: Enantiotopic, RS-diastereotopic, and holantitopic relationships. Among them, the term enantiotopic is used to specify the term prochirality, while the term RS-diastereotopic is used to specify the term pro-RS-stereogenicity. The term pro-RS-stereogenicity is clarified to correspond to the pro-R/pro-S-nomenclature, just as the term RS-stereogenicity corresponds to the RS-nomenclature. Substitution criteria based on stereoisograms are introduced to determine pro-RS-stereogenicity as well as prochirality.
