On the Interaction Between Deprotonated Cytosine (C-H)- and Ba2+: Infrared Multiphoton spectroscopy and dynamics

CRUZ-ORTIZ, ANDRÉS FELIPE; TACCONE, MARTÍN IGNACIO; MAITRE, PHILIPPE; ROSSA, MAXIMILIANO; PINO, GUSTAVO ARIEL

Chemphyschem

WILEY-V C H VERLAG GMBH

Año: 2020 vol. 21 p. 2571 - 2571

1439-4235

as-phase interactions between Ba2+ and deprotonated cytosine (C(-H)) were studied in [C(-H)Ba]+ and [C(-H)BaC]+ complexes by IRMPD spectroscopy coupled to tandem mass-spectrometry in combination with DFT calculations. For the [C(-H)BaC]+complex only one [C(-H)KAN1O-Ba-Canti]+ isomer was found, although the presence of another structure cannot be neglected. This isomer features a central tetracoordinated Ba2+ that simultaneously interacts with keto-amino [C(-H)]- deprotonated on N1 and neutral keto-amino C. Both moieties are in different planes as a consequence of an additional NH●●●O=C hydrogen bond between C and [C(-H)]-. A sequential IRMPD dynamics is observed in this complex. For the [C(-H)Ba]+ complex produced by electrospray ionization two isomers ([C(-H)KAN1OBa]+ and [C(-H)KAN3OBa]+) were identified, in which Ba2+ interacts simultaneously with the C=O group and the N1 or N3atom of the keto-amino [C(-H)]-, respectively. A comparison with the related [C(-H)Pb]+ c