Related Experiment Video
Updated: May 20, 2025
11:04
Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
2.9K
Racemic drugs are not necessarily less efficacious and less safe than their single-enantiomer components
Israel Agranat1, Ilaria D'Acquarica2
1Organic Chemistry, Institute of Chemistry, The Hebrew University of Jerusalem, Edmond J. Safra Campus, Jerusalem 9190401, Israel.
Summary
Chiral drug development should prioritize racemates unless a single enantiomer shows a distinct advantage. Recent claims favoring single enantiomers over racemates are challenged, advocating for a case-by-case evaluation.
Area of Science:
- Medicinal Chemistry
- Pharmacology
- Drug Development
Background:
- Chiral drugs present a development dilemma: racemate versus single enantiomer.
- Recent publications (2024) claim single enantiomers offer superior clinical potency, efficacy, and safety compared to racemates.
- These claims necessitate a critical re-evaluation of current chiral drug development strategies.
Purpose of the Study:
- To rebut recent allegations favoring single enantiomer drugs over racemates.
- To provide a historical perspective on the development of single enantiomer drugs.
- To analyze cases where racemates or diastereomeric mixtures are preferred over single enantiomers.
Main Methods:
- Historical survey of motivations for single enantiomer drug development.
- Case study analysis of racemate/diastereomeric mixture preference over single enantiomers.
- Examination of 'teaching away' cases from chiral switches (e.g., in vivo interconversion, enantiomerization).
Main Results:
- Racemate/diastereomeric mixture drugs are not inherently less efficacious or safe than single enantiomer components.
- Specific scenarios exist where racemates are preferred, including rapid in vivo interconversion or enantiomerization.
- Advantages and disadvantages of both racemic and single enantiomer drugs are detailed.
Conclusions:
- Racemate/diastereomeric mixture drugs remain viable candidates for chiral switches.
- Development of chiral drugs should proceed with the racemate by default.
- A single enantiomer should only be pursued if a relevant, differentiated property is identified.
Related Concept Videos
02:30Racemic Mixtures and the Resolution of Enantiomers
17.9K
A racemic mixture, or racemate, is an equimolar mixture of enantiomers of a molecule that can be separated using their unique interaction with chiral molecules or media. Racemic mixtures are denoted by the (±)- prefix. This ‘optical rotation descriptor’ applies to the whole solution of a racemic mixture rather than a specific stereoisomer. Enantiomers typically have the same physical and chemical properties. Hence, they are not easily separable. However, enantiomers can exhibit...
17.9K
02:24Properties of Enantiomers and Optical Activity
16.6K
It is essential to understand the difference between chiral and achiral interactions and the implications thereof in optical activity and their applications. Just as our feet, which are chiral, interact uniquely with chiral objects, such as a pair of shoes, but identically with achiral socks, enantiomers of a molecule exhibit different properties only when they interact with other chiral media. An example of a significant implication from this facet is the phenomenon known as optical activity,...
16.6K
02:30Chirality in Nature
12.5K
Chirality is the most intriguing yet essential facet of nature, governing life’s biochemical processes and precision. It can be observed from a snail shell pattern in a macroscopic world to an amino acid, the minutest building block of life. Most of the snails around the world have right-coiled shells because of the intrinsic chirality in their genes. All the amino acids present in the human body exist in an enantiomerically pure state, except for glycine - the sole achiral amino acid.
12.5K
02:32Stereoisomers
12.4K
On the basis of mirror symmetry, stereoisomers of an organic molecule can be further classified into diastereomers and enantiomers. Diastereomers are stereoisomers that are not mirror images of each other. Substituted alkenes, such as the cis and trans isomers of 2-butene, are diastereomers, as these molecules exhibit different spatial orientations of their constituent atoms, are not mirror images of each other, and do not interconvert. Here, the interconversion is suppressed due to...
12.4K
01:22Dose-Response Relationship: Potency and Efficacy
4.1K
The potency of a drug is the measure of its ability to produce a biological response and can be compared by looking at the half-maximum effective concentration or EC50 values of different drugs. A lower EC50 value indicates higher potency of the drug. In the dose–response curve of two antihypertensive drugs, candesartan and irbesartan, a significant difference is observed in their EC50 values. A lower EC50 value for candesartan indicates that it is more potent than irbesartan, as it...
4.1K
01:20Factors Affecting Dissolution: Drug Permeability, Stability and Stereochemistry
162
Orally administered drugs primarily enter the systemic circulation via passive diffusion through the intestinal membranes. The drug's absorption is influenced by drug stability in the gastrointestinal GI tract, membrane permeability, the surface area available for absorption, luminal drug concentration, and residence time in the lumen. Drug permeability can be enhanced by adjusting the lipophilicity, polarity, or molecular size of the drug, promoting its passive transport across intestinal...
162