(R)and(S)Nomenclature OH HO CH; NH2 HN CH natural alanine unnatural alanine Copyright2010 Pearson Prentice Hall,Inc Different molecules (enantiomers)must have different names. Usually only one enantiomer will be biologically active. Configuration around the chiral carbon is specified with (R)and (S). Chapter 5 9Chapter 5 9 (R) and (S) Nomenclature • Different molecules (enantiomers) must have different names. • Usually only one enantiomer will be biologically active. • Configuration around the chiral carbon is specified with (R) and (S)