title: Force-field and quantum-mechanical binding study of selected SAMPL3 host-guest complexes.
abstract: A Merck molecular force field classical potential combined with Poisson-Boltzmann electrostatics (MMFF/PB) has been used to estimate the binding free energy of seven guest molecules (six tertiary amines and one primary amine) into a synthetic receptor (acyclic cucurbit[4]uril congener) and two benzimidazoles into cyclic cucurbit[7]uril (CB[7]) and cucurbit[8]uril (CB[8]) hosts. In addition, binding enthalpies for the benzimidazoles were calculated with density functional theory (DFT) using the B3LYP functional and a polarizable continuum model (PCM). Although in most cases the MMFF/PB approach returned reasonable agreements with the experiment (±2 kcal/mol), significant, much larger deviations were reported in the case of three host-guest pairs. All four binding enthalpy predictions with the DFT/PCM method suffered 70% or larger deviations from the calorimetry data. Results are discussed in terms of the molecular models used for guest-host complexation and the quality of the intermolecular potentials.
authors.affiliation: OpenEye Scientific Software, 9 Bisbee Court, Suite D, Santa Fe, NM 87508, USA.
authors.forename: Nobuko
authors.initials: N
authors.lastname: Hamaguchi
authors.forename: Laszlo
authors.initials: L
authors.lastname: Fusti-Molnar
authors.forename: Stanislaw
authors.initials: S
authors.lastname: Wlodek
mesh_terms: D000588:Amines / Q000737:chemistry*; D001562:Benzimidazoles / Q000737:chemistry; D001952:Bridged-Ring Compounds / Q000737:chemistry; D002151:Calorimetry; D007093:Imidazoles / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D013816:Thermodynamics; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils
chemical_list: D000588:Amines; D001562:Benzimidazoles; D001952:Bridged-Ring Compounds; D007093:Imidazoles; C456276:cucurbit(7)uril; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils; C507198:cucurbit(8)uril