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Updated: Oct 11, 2026

Quantifying Agonist Activity at G Protein-coupled Receptors
Published on: December 26, 2011
Structure-activity relationships on adrenoceptors and imidazoline-preferring binding sites (I(1,2)-PBSs). Part 1:
1Laboratoire de Pharmacochimie Moléculaire et Systèmes Membranaires, Université Paris 7-Denis Diderot, France.
Abstract:
The highly selective I1-PBS imidazoline analogue PMS 952 has been selected to study the incidence of intramolecular hydrogen bond and molecular flexibility on its biological activity. On one hand, the weak energy difference between three calculated conformers does not support the stabilization of one conformer by an internal hydrogen bond. The 3-D electrostatic map confirms this feature and the solvent effect does not significantly modify the relative energy of these conformers. On the other hand, the conformational spaces of the neutral and ionized forms present a great number of equilibrium structures, in a short energetic range (20 Kcal). The results are representative of an exceptional conformational flexibility due to a cooperative effect between several parts of the molecule.
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