Tautomeric transformation of temozolomide, their proton affinities and chemical reactivities: A theoretical approach

Wichien Sang-Aroon; Vithaya Ruangpornvisuti; Vittaya Amornkitbamrung

doi:10.1016/j.jmgm.2016.03.016

Tautomeric transformation of temozolomide, their proton affinities and chemical reactivities: A theoretical approach

J Mol Graph Model. 2016 May:66:76-84. doi: 10.1016/j.jmgm.2016.03.016. Epub 2016 Mar 26.

Authors

Wichien Sang-Aroon¹, Vithaya Ruangpornvisuti², Vittaya Amornkitbamrung³

Affiliations

¹ Department of Chemistry, Faculty of Engineering, Rajamangala University of Technology Isan, KhonKaen Campus, KhonKaen 40000, Thailand; Integrated Nanotechnology Research Center, Department of Physics, Faculty of Science, KhonKaen University, KhonKaen 40002, Thailand. Electronic address: wichien.sa@rmuti.ac.th.
² Supramolecular Chemistry Research Unit, Department of Chemistry, Faculty of Science, Chulalongkorn University, Pathumwan, Bangkok 10320, Thailand.
³ Integrated Nanotechnology Research Center, Department of Physics, Faculty of Science, KhonKaen University, KhonKaen 40002, Thailand; Thailand Center of Excellence in Physics, CHE, Ministry of Education, Bangkok 10400, Thailand. Electronic address: vittaya@kku.ac.th.

PMID: 27041447
DOI: 10.1016/j.jmgm.2016.03.016

Abstract

The gas-phase geometry optimizations of bare, mono- and dihydrated complexes of temozolomide isomers were carried out using density functional calculation at the M06-2X/6-31+G(d,p) level of the theory. The structures and protonation energies of protonated species of temozolomide are reported. Chemical indices of all isomers and protonated species are also reported. Energies, thermodynamic quantities, rate constants and equilibrium constants of tautomeric and rotameric transformations of all isomers I1↔TZM↔HIa↔HIb↔I2↔I3 in bare and hydrated systems were obtained.

Keywords: Chemical reactivity; Proton affinity; Rate constants; Reaction energy; Temozolomide isomers; Thermodynamic properties.

MeSH terms

Dacarbazine / analogs & derivatives*
Dacarbazine / chemistry
Gases / chemistry
Isomerism
Models, Theoretical
Protons*
Quantum Theory*
Temozolomide
Thermodynamics*

Substances

Gases
Protons
Dacarbazine
Temozolomide