Conformational flexibility in hydrated sugars: the glycolaldehyde-water complex.
Conformational flexibility in the smallest hydrated sugar, the glycolaldehyde-water complex, has been investigated in the gas phase by means of a combination of a microwave Fourier transform spectroscopy experiment in a supersonic molecular beam and ab initio quantum chemistry calculations. The water molecule inserts into glycolaldehyde using H-bonding selectivity: the two lowest energy conformations are stabilized by two intermolecular hydrogen bonds, and the next two by one intra- plus one intermolecular hydrogen bond. A dynamical flexibility associated with the two lowest energy conformations has been experimentally observed and accurately modeled with a two-dimensional potential energy surface involving the hydroxyl group and the free OH water group coordinates. The conclusions drawn from the role played in the conformational flexibility by the hydroxyl and carbonyl groups are extended to other carbohydrates and biomolecules.
Aviles-Moreno
Juan-Ramon
JR
Contribution from the Laboratoire de Physique des Lasers, Atomes et Molécules, Bâtiment P5, UMR 8523 CNRS, Université Lille 1, F-59655 Villeneuve d'Ascq Cedex, France.
Demaison
Jean
J
Huet
Thérèse R
TR
D000079:Acetaldehyde / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D002241:Carbohydrates / Q000737:chemistry*; D005740:Gases / Q000737:chemistry; D008956:Models, Chemical; D008968:Molecular Conformation; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared; D014867:Water / Q000737:chemistry* / Q000378:metabolism
D002241:Carbohydrates; D005740:Gases; D014867:Water; D000079:Acetaldehyde; C010972:glycolaldehyde