Related Experiment Video
Updated: Sep 29, 2026

Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
Published on: June 27, 2014
Stereochemical study of tolperisone, a muscle relaxant agent, by circular dichroism and ultraviolet spectroscopy
F Zsila1, M Hollósi, A Gergely
1Department of Molecular Pharmacology, Institute of Chemistry, Budapest, Hungary. ZSFERI@CRIC.CHEMRES.HU
Abstract:
The stereochemistry of tolperisone, a chiral aryl-alkyl basic ketone was investigated by means of circular dichroism (CD) and ultraviolet (UV) spectroscopy. The unusually high optical activity of tolperisone hydrochloride in the n-->pi* region is interpreted by the presence of a chiral conformer in solution. For stereochemical reasons, the C = O group and the aromatic moiety lack coplanarity by forming an inherently dissymetric chromophore, of M helicity. Similar helicity prevails in the crystal phase, according to the solid-state CD spectrum of (-)-tolperisone HCl salt. The chirality rule proposed by Snatzke for nonplanar benzoyl chromophores predicts the absolute configuration of (-)-tolperisone hydrochloride to be R, in agreement with other alpha-methyl-beta-amino-ketones.
Related Concept Videos
Stereoisomerism of Cyclic Compounds
¹H NMR of Conformationally Flexible Molecules: Temporal Resolution
¹³C NMR: Distortionless Enhancement by Polarization Transfer (DEPT)
¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR
Classification of Skeletal Muscle Relaxants
Peripherally acting skeletal muscle relaxants interfere with the neurotransmission at the neuromuscular end plate to induce paralysis during...
Peripherally and Centrally Acting Muscle Relaxants: A Comparison
Centrally acting muscle relaxants can be further divided into spasmolytic and antispasmodic drugs. Spasmolytic drugs,...

