Multiple Descriptors in One Molecule
If a compound has more than one stereocenter each center is denoted by either R or S.
For example, ephedrine exists with both (1R,2S) and (1S,2R) configuration, known as diastereomers. This compound also exists with a (1R,2R) and (1S,2S) configuration. The last two stereoisomers are not ephedrine, but pseudoephedrine. All isomers are 2-methylamino-1-phenyl-1-propanol in systematic nomenclature. Pseudoephedrine is chemically distinct from ephedrine with only the three dimensional configuration in space, as notated by the Cahn–Ingold–Prelog rules.
Read more about this topic: Cahn–Ingold–Prelog Priority Rules
Famous quotes containing the words multiple and/or molecule:
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