Guanine Tautomerism in Ionic Complexes with Ag + Investigated by IRMPD Spectroscopy and Mass Spectrometry

Autor: Gustavo A. Pino, Andrés F. Cruz-Ortiz, Philippe Maître, Franco L. Molina
Přispěvatelé: Instituto de Investigaciones en Físico Química [Córdoba] (INFIQC), Consejo Nacional de Investigaciones Científicas y Técnicas [Buenos Aires] (CONICET)-Facultad de Ciencias Químicas [Córdoba], Universidad Nacional de Córdoba [Argentina]-Universidad Nacional de Córdoba [Argentina], Institut de Chimie Physique (ICP), Institut de Chimie du CNRS (INC)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Journal of Physical Chemistry B
Journal of Physical Chemistry B, American Chemical Society, 2021, 125 (26), pp.7137-7146. ⟨10.1021/acs.jpcb.1c03796⟩
The journal of physical chemistry. B
ISSN: 1520-6106
1520-5207
Popis: In this paper, we present the IRMPD spectra of three ionic complexes between guanine (G) and silver (Ag+): [GAg-H2O]+, [GAgG]+ produced in the electrospray ionization source of the mass spectrometer, and [GAg]+ produced by collision induced dissociation of the [GAgG]+ complex. On the basis of the comparison of theoretically calculated IR spectra, we show that there are two isomers of each complex containing two different keto-amino (KA) tautomers of G (GKA(1,9) and GKA(1,7)). The observed isomers are the most stable structures in aqueous solution, and their experimentally estimated relative populations are in better agreement with the calculated relative populations in solution than in the gas phase, both at 298 K. We concluded that these observations suggest that GKA(1,9) and GKA(1,7) coexist in solution according to previous theoretical reports (Colominas, C.; et al. J. Am. Chem. Soc. 1996, 118, 6811). We were unable to find any evidence of the presence of the GEA(9), GKA(3,7), GKA(3,9), or GKA(7,9), whose relative stabilities in solution are strongly dependent on the theoretical method used to account for the solvent effect (Hanus, M.; et al. J. Am. Chem. Soc. 2003, 125, 7678).
Databáze: OpenAIRE