An ab initio quantum mechanical study of the bis-benzimidazole derivative Hoechst 33342 is presented. Specifically, we report on the molecular geometry, proton affinity, gas-phase basicity, hydration, pKa, and molecular interaction potential map of Hoechst 33342 and the forms obtained by its protonation and deprotonation. Results have been compared with those obtained for Hoechst 33258 to analyze the influence of the chemical structure on the properties of this bis-benzimidazole derivative. Finally, the connection of some theoretical predictions with experimental evidences has been examined.

中文翻译：

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Hoechst 33342的酸碱和电子结构依赖性。

提出了双苯并咪唑衍生物Hoechst 33342的从头算量子力学研究。具体来说，我们报告了Hoechst 33342的分子几何结构，质子亲和力，气相碱度，水合度，pKa和分子相互作用势图以及通过其质子化和去质子化获得的形式。将结果与从Hoechst 33258获得的结果进行了比较，以分析化学结构对该双苯并咪唑衍生物的性能的影响。最后，研究了一些理论预测与实验证据之间的联系。