#chirality

Ibuprofen

Leave a Comment / Chiral Pharmacology, Chiral science / By / , , / September 29, 2025

Ibuprofen is a widely used non-steroidal anti-inflammatory drug (NSAID). It is a monocarboxylic acid that is propionic acid in which one of the hydrogens at position 2 is substituted by a 4-(2-methylpropyl)phenyl group. Hence belongs to the propionic acid derivative class of NSAIDs. It is commonly prescribed for pain, inflammation, and fever. Available as over-the-counter (OTC) and prescription medication worldwide. Chirality and Biological Activity Structurally, Ibuprofen is a chiral molecule with one stereogenic center at the α-position …

Ibuprofen Read More »

Part 8: Stereochemistry in Biologics and Natural Products

Leave a Comment / Stereochemistry / By / , / October 3, 2025

“Nature’s stereochemists – chirality in biologics, peptides, and natural products” Introduction Stereochemistry is inherent in biological macromolecules and natural products. This part explores chirality beyond small synthetic drugs – specifically, in biologics (peptides, proteins, nucleic acids) and in natural product-derived drugs. We examine how nature’s biosynthetic machinery imparts stereochemistry with high fidelity (e.g., enzymes produce single enantiomers of amino acids, sugars, complex polyketides). We discuss examples of drugs that are derived from natural chirality (like …

Part 8: Stereochemistry in Biologics and Natural Products Read More »

Part 5: Stereoselective and Stereospecific Synthesis

Leave a Comment / Stereochemistry / By / , , / September 10, 2025

“Crafting molecules with precision – the art of stereochemical synthesis” Introduction Having seen why the correct stereochemistry is crucial for drug efficacy and safety, the next challenge is how to obtain the desired stereoisomer. This part covers strategies and methods in stereoselective and stereospecific synthesis. We clarify the terminology: a stereoselective reaction preferentially yields one stereoisomer over others (e.g., one enantiomer or one diastereomer is favored), whereas a stereospecific reaction produces different stereoisomeric products from …

Part 5: Stereoselective and Stereospecific Synthesis Read More »

Part 4: Stereochemistry in Drug Action and Pharmacology

Leave a Comment / Stereochemistry / By / , / October 2, 2025

“Why one enantiomer heals while the other may harm – the pharmacology of chirality” Introduction Chirality doesn’t just influence drug properties in theory – it has very real consequences in pharmacology. In this section, we explore how stereochemistry affects drug action at multiple levels: pharmacodynamics (drug-receptor interactions) and pharmacokinetics (absorption, distribution, metabolism, excretion). We will define terms like eutomer (the more active enantiomer) and distomer (the less active one) and introduce the concept of the …

Part 4: Stereochemistry in Drug Action and Pharmacology Read More »

Part 3: Nomenclature and Configuration

Leave a Comment / Stereochemistry / By / , , / September 4, 2025

“Decoding the rules: how chemists name and navigate molecular twists.” Introduction Correctly describing the stereochemistry of a molecule is as important as understanding it. In this part, we focus on the Cahn–Ingold–Prelog (CIP) system, which provides the rules for unambiguous assignment of absolute configuration at stereocenters (R/S) and for double bond geometry (E/Z) system. We will outline the CIP priority rules step-by-step and demonstrate how to apply them to pharmaceutical molecules. Additionally, we will discuss …

Part 3: Nomenclature and Configuration Read More »

Part 1: Introduction to Stereochemistry

Leave a Comment / Chirality, Stereochemistry / By / , , / August 27, 2025

“The 3D language of molecules – why stereochemistry is the hidden key in drug science.” Introduction Stereochemistry is the branch of chemistry concerned with the three-dimensional arrangement of atoms in molecules and how this spatial arrangement influences chemical behavior. The term “chirality” (from the Greek cheir meaning hand) describes the property of an object or molecule that is non-superimposable on its mirror image – much like one’s left and right hands. A molecule that exhibits …

Part 1: Introduction to Stereochemistry Read More »

Mapping Stereochemical Nomenclature: A Chiralpedia Guide

Leave a Comment / Chiral science / By / , , / August 21, 2025

Stereochemistry, the study of spatial arrangements of atoms in molecules, demands a precise and universally accepted nomenclature system. Unlike simple chemical formulas, which only indicate connectivity, stereochemical nomenclature conveys three-dimensional information essential for understanding molecular behavior, biological interactions, and pharmaceutical effects. Several systems have been developed to capture these subtle but critical differences. 🔬✨ Stereochemical Nomenclature System — Now in a Visual Story! Stereochemical naming systems are often tucked away in textbooks 📚, dense and …

Mapping Stereochemical Nomenclature: A Chiralpedia Guide Read More »

The Thalidomide Paradox

Leave a Comment / Chirality / By / , , / August 14, 2025

Synopsis The thalidomide tragedy is one of the most infamous episodes in pharmaceutical history—yet its stereochemical secrets are still being unraveled. A fascinating article by Tokunaga E, Yamamoto T, Ito E, and Shibata N., published in Scientific Reports (Nature Research, 2018; https://www.nature.com/articles/s41598-018-35457-6), sheds new light on the phenomenon through the lens of the self-disproportionation of enantiomers, the physical chemistry of chirality. Thalidomide’s tragic past is linked to its two “mirror-image” forms. One form, the S-enantiomer, …

The Thalidomide Paradox Read More »

Episode 10: Future Reflections: How the Story of Chiral Drug Regulation Continues

Leave a Comment / Chiral science, Chirality, Regulatory Affairs / By / , / June 21, 2025

“Approval is not the end of a molecule’s journey – the mirror must be watched, studied, and questioned throughout its life.” Introduction The development and approval of chiral drugs, especially single-enantiomer entities, marked a new chapter in pharmaceutical science. However, approval is only the beginning. Ensuring that a chiral drug continues to behave safely and predictably in the real world demands vigilant post-marketing surveillance, adaptive regulatory frameworks, and constant scientific reevaluation. In this final episode, …

Episode 10: Future Reflections: How the Story of Chiral Drug Regulation Continues Read More »

Episode 9: Challenges on the Horizon: Complex Chirality and Emerging Scientific Questions

Leave a Comment / Chiral science, Chirality, Regulatory Affairs / By / , / June 17, 2025

“As the molecular world grows more intricate, so do the challenges in regulating and understanding chirality.” Introduction While the 1990s and 2000s solidified regulatory frameworks for simple chiral drugs -classic single stereocenter, stable enantiomers –science has since moved into more complex territory. Today, pharmaceutical innovation increasingly deals with molecules featuring multiple stereocenters, dynamic chirality, axial chirality (atropisomerism), and stereochemical instability. These new realities stretch the existing regulatory and scientific paradigms developed for simpler chiral systems. …

Episode 9: Challenges on the Horizon: Complex Chirality and Emerging Scientific Questions Read More »