Optical Isomers — Definition, Formula, Properties & Uses | AllChemicals | AllChemicals

Also Known As	Enantiomers, chiral isomers, R/S isomers, mirror image isomers, optical isomers

What is Optical Isomers?

Stereoisomers that are non-superimposable mirror images (enantiomers) or differ in the configuration of one or more chiral centers while having the same connectivity (diastereomers). They rotate plane-polarized light and are important in pharmaceuticals and biochemistry.

Properties & Characteristics

Optical isomers (enantiomers) are stereoisomers that are non-superimposable mirror images of each other, possessing chiral centres (usually a carbon atom with 4 different substituents). They rotate plane-polarised light in opposite directions (optical activity). The R/S designation (Cahn-Ingold-Prelog rules) specifies absolute configuration. Racemic mixtures (50:50 enantiomers) have zero net optical rotation. Diastereomers are stereoisomers that are not mirror images.

Uses & Applications

Optical isomers are critically important in: pharmaceuticals (enantiomeric purity required by FDA/EMA; thalidomide, ibuprofen), biochemistry (enzymes are stereospecific — L-amino acids and D-sugars), agrochemicals (single-enantiomer herbicides and insecticides), and asymmetric synthesis (producing single enantiomers using chiral catalysts).

Safety Information

The two enantiomers of a chiral drug may differ in efficacy and toxicity (eutomer vs. distomer). Racemic ibuprofen is safe (R→S conversion in vivo), but racemic thalidomide is teratogenic due to the S-(−)-enantiomer. Single-enantiomer drugs require chiral synthesis, chiral resolution, or biocatalysis — and strict chiral purity testing.

Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.

Key Facts

Term Optical Isomers

Index All "O" terms

Synonyms Enantiomers, chiral isomers, R/S isomers, mirror image isomers, optical isomers

Frequently Asked Questions

What is Optical Isomers?

Stereoisomers that are non-superimposable mirror images (enantiomers) or differ in the configuration of one or more chiral centers while having the same connectivity (diastereomers). They rotate plane-polarized light and are important in pharmaceuticals and biochemistry.

What is Optical Isomers used for?

Is Optical Isomers hazardous?

More "O" Terms

Octahedral ML₆ Octane Number Octet Rule Octet Rule Oganesson Og Oil Open Sextet Open System Optical Activity Optical Isomers Orbital ψ(r,θ,φ): quantum wavefunction squared gives probability density Orbital Hybridization

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