AUTHOR=Arthur-Baidoo Eugene , Izadi Farhad , Guerra Carlos , Garcia Gustavo , Ončák Milan , Denifl Stephan 

TITLE=Dynamics of Ring-Cleavage Reactions in Temozolomide Induced by Low-Energy Electron Attachment

JOURNAL=Frontiers in Physics

VOLUME=10

YEAR=2022

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2022.880689

DOI=10.3389/fphy.2022.880689

ISSN=2296-424X

ABSTRACT=<p>We have used a crossed electron molecular beam setup to investigate the behavior of the anticancer drug temozolomide (TMZ) upon the attachment of low-energy electrons (0–14 eV) in the gas phase. Upon a single electron attachment, eight anionic fragments are observed, the most intense being an anion with mass of 109 u at a resonance energy of 0 eV. Quantum chemical calculations suggest that this ion is generated after the tetrazine ring opens along a N–N bond and its fragments leave the molecule, forming an imidazole-carboxamide species. This ion represents the most abundant fragment, with further fragments following from its dissociation. The tetrazine ring cleavage reaction forming N<sub>2</sub> is thus the driving force of TMZ reactivity upon electron attachment.</p>