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Transport Properties of Ibuprofen Encapsulated in Cyclodextrin Nanosponge Hydrogels: A Proton HR-MAS NMR Spectroscopy Study
Published on: August 15, 2016
Assessing the stable conformations of ibuprofen in solution by means of Residual Dipolar Couplings
Maria Enrica Di Pietro1, Giorgio Celebre1, Christie Aroulanda2
1Lab. LXNMR_S.C.An., Dipartimento di Chimica e Tecnologie Chimiche, Università della Calabria, Via P. Bucci, 87036 Arcavacata di Rende (CS), Italy.
Abstract:
Detailing the conformational equilibria between global and local minimum energy structures of anti-inflammatory α-arylpropionic acids directly in solution is of the utmost importance for a better understanding of the structure-activity relationships, hence providing valuable clues for rational structure-based drug design studies. Here the conformational preferences of the widely used pharmaceutical ibuprofen were investigated in solution by NMR spectroscopy in weakly ordering phases. A thorough theoretical treatment of the anisotropic interactions that are relevant for NMR spectra led to a conformational model characterized by six pairs of symmetry-related conformers, in particular four couples of gauche structures, with a total probability of 93%, and 2 couples of trans structures, counting for the remaining 7%.
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