Spatial structure of felodipine dissolved in DMSO by 1D NOE and 2D NOESY NMR spectroscopy

Small organic molecules in dissolved state exist as an ensemble of conformers. In this work conformation of felodipine in dimethyl sulphoxide was studied and dominant stable conformers were determined. Effective interatomic distances were obtained by means of NOE spectroscopy. Fractions of different conformers were estimated by comparing effective distances and those obtained from quantum-chemical calculation [8]; averaging of distances was made following the N-site jump model.

► Internuclear distances in felodipine were obtained by analysis of 1D and 2D NOE data.
► Obtained effective distances were compared with quantum-chemical calculations.
► Fractions of different conformers of felodipine dissolved in DMSO were estimated.