title: Molecular recognition in glycolaldehyde, the simplest sugar: two isolated hydrogen bonds win over one cooperative pair.
abstract: Carbohydrates are used in nature as molecular recognition tools. Understanding their conformational behavior upon aggregation helps in rationalizing the way in which cells and bacteria use sugars to communicate. Here, the simplest α-hydroxy carbonyl compound, glycolaldehyde, was used as a model system. It was shown to form compact polar C 2-symmetric dimers with intermolecular O-H⋅⋅⋅O=C bonds, while sacrificing the corresponding intramolecular hydrogen bonds. Supersonic jet infrared (IR) and Raman spectra combined with high-level quantum chemical calculations provide a consistent picture for the preference over more typical hydrogen bond insertion and addition patterns. Experimental evidence for at least one metastable dimer is presented. A rotational spectroscopy investigation of these dimers is encouraged, also in view of astrophysical searches. The binding motif competition of aldehydic sugars might play a role in chirality recognition phenomena of more complex derivatives in the gas phase.
authors.affiliation: Institut für Physikalische Chemie, Universität Göttingen Tammannstr. 6, 37077 Göttingen (Germany) E-mail: msuhm@gwdg.de.
authors.forename: Jonas
authors.initials: J
authors.lastname: Altnöder
authors.affiliation: Institut für Physikalische Chemie, Universität Göttingen Tammannstr. 6, 37077 Göttingen (Germany) E-mail: msuhm@gwdg.de.
authors.forename: Juhyon J
authors.initials: JJ
authors.lastname: Lee
authors.affiliation: Institut für Physikalische Chemie, Universität Göttingen Tammannstr. 6, 37077 Göttingen (Germany) E-mail: msuhm@gwdg.de.
authors.forename: Katharina E
authors.initials: KE
authors.lastname: Otto
authors.affiliation: Institut für Physikalische Chemie, Universität Göttingen Tammannstr. 6, 37077 Göttingen (Germany) E-mail: msuhm@gwdg.de.
authors.forename: Martin A
authors.initials: MA
authors.lastname: Suhm
keywords: Raman spectroscopy; ab initio calculations; carbohydrates; conformational analysis; infrared spectroscopy; molecular recognition