title: Selective bond cleavage in potassium collisions with pyrimidine bases of DNA.
abstract: Electron transfer in alkali-molecule collisions to gas phase thymine and uracil yielding H- formation is selectively controlled in the energy range between 5.3 and 66.1 eV. By tuning the collision energy, electron transfer from the alkali to partly deuterated thymine, methylated thymine at the N1 and methylated uracil at the N3 positions, H- loss proceeds not only through the breaking of the (C-H) against (N-H) bonds but also through N1 against N3 sites. Such selectivity, as far as bond and site are concerned, is here reported for the first time by electron transfer induced dissociation experiments in alkali-molecule collisions.
authors: Laboratório de Colisões Atómicas e Moleculares, CEFITEC, Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.
authors: Diogo
authors: D
authors: Almeida
authors: Filipe
authors: F
authors: Ferreira da Silva
authors: Gustavo
authors: G
authors: García
authors: Paulo
authors: P
authors: Limão-Vieira
mesh_terms: D002414:Cations, Monovalent / Q000737:chemistry; D004247:DNA / Q000737:chemistry*; D013058:Mass Spectrometry; D008956:Models, Chemical; D011188:Potassium / Q000737:chemistry*; D011743:Pyrimidines / Q000737:chemistry*; D055672:Static Electricity; D013816:Thermodynamics; D013941:Thymine / Q000737:chemistry; D014498:Uracil / Q000737:chemistry
chemical_list: D002414:Cations, Monovalent; D011743:Pyrimidines; D014498:Uracil; D004247:DNA; D013941:Thymine; D011188:Potassium