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Updated: Jul 30, 2026
09:54
Chemoselective Preparation of 1-Iodoalkynes, 1,2-Diiodoalkenes, and 1,1,2-Triiodoalkenes Based on the Oxidative Iodination of Terminal Alkynes
Published on: September 12, 2018
New single-isomer compounds on the horizon
1Division of Clinical Pharmacology, University of Colorado School of Medicine, Denver, Colorado, USA.
CNS Spectrums
|May 8, 2004
Summary
The FDA encourages single-isomer drug development, leading to safer and more effective chiral drugs. Three main strategies are chiral switches, chiral metashifts, and new single-isomer chemical entities.
Area of Science:
- Pharmaceutical Chemistry
- Drug Development
- Chirality in Medicine
Background:
- The U.S. Food and Drug Administration (FDA) issued guidelines in 1992 promoting single-isomer drug development over racemic mixtures.
- This has led to a significant shift towards developing chiral drugs as single enantiomers for improved therapeutic profiles.
Purpose of the Study:
- To outline the mechanisms and significance of developing single-isomer drugs.
- To highlight the advantages of single-isomer drugs over racemic mixtures in terms of efficacy and safety.
Main Methods:
- Identification and categorization of three primary pathways for single-isomer drug development: chiral switches (CS), chiral metashifts (CM), and new single-isomer chemical entities (NSICEs).
- Review of current and developing drugs within each category, citing examples such as (S)-oxybutynin, escitalopram, (+)-norcisapride, (S)-desmethylzopiclone, rosuvastatin, and pregabalin.
Main Results:
- Chiral switches involve developing one enantiomer of an existing racemic drug.
- Chiral metashifts focus on developing active chiral metabolites as single isomers.
- Numerous new single-isomer chemical entities are under development across various therapeutic areas.
Conclusions:
- The transition to single-isomer drug development represents a significant advancement in creating safer and more effective pharmaceuticals.
- While not all candidates succeed, the trend towards single enantiomers promises improved patient outcomes.
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