Kasende Okuma Emile, Muya Jules Tshishimbi, de Paul N Nziko Vincent, Scheiner Steve
Faculty of Science, University of Kinshasa, B.P. 190, Kinshasa XI, Democratic Republic of the Congo.
Department of Chemistry & Biochemistry, Utah State University, Logan, UT, 84322-0300, USA.
J Mol Model. 2016 Apr;22(4):77. doi: 10.1007/s00894-016-2934-z. Epub 2016 Mar 14.
Dispersion-corrected density functional theory (DFT) and MP2 quantum chemical methods are used to examine homodimers of temozolomide (TMZ). Of the 12 dimer configurations found to be minima, the antarafacial stacked dimer is the most favored, it is lower in energy than coplanar dimers which are stabilized by H-bonds. The comparison between B3LYP and B3LYP-D binding energies points to dispersion as a primary factor in stabilizing the stacked geometries. CO(π) → CO(π*) charge transfers between amide groups in the global minimum are identified by NBO, as well as a pair of weak CH∙∙N H-bonds. AIM analysis of the electron density provides an alternative description which includes N∙∙O, N∙∙N, and C∙∙C noncovalent bonds.
采用色散校正密度泛函理论（DFT）和MP2量子化学方法研究替莫唑胺（TMZ）的同二聚体。在发现的12种二聚体构型中，反式堆积二聚体最受青睐，其能量低于通过氢键稳定的共平面二聚体。B3LYP和B3LYP-D结合能之间的比较表明，色散是稳定堆积几何结构的主要因素。自然键轨道（NBO）确定了全局最小值中酰胺基团之间的CO(π) → CO(π*)电荷转移，以及一对弱CH∙∙N氢键。电子密度的AIM分析提供了另一种描述，其中包括N∙∙O、N∙∙N和C∙∙C非共价键。
