Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China.
School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou 215009, China.
Molecules. 2023 Jun 7;28(12):4620. doi: 10.3390/molecules28124620.
Citalopram (CIT) is a commonly prescribed medication for depression. However, the photodegradation mechanism of CIT has not yet been fully analyzed. Therefore, the photodegradation process of CIT in water is studied by density functional theory and time-dependent density functional theory. The calculated results show that during the indirect photodegradation process, the indirect photodegradation of CIT with ·OH occurs via OH-addition and F-substitution. The minimum activation energy of C10 site was 0.4 kcal/mol. All OH-addition and F-substitution reactions are exothermic. The reaction of O with CIT includes the substitution of O for F and an addition reaction at the C14 site. The value of this process is 1.7 kcal/mol, which is the lowest activation energy required for the reaction of O with CIT. C-C/C-N/C-F cleavage is involved in the direct photodegradation process. In the direct photodegradation of CIT, the activation energy of the C7-C16 cleavage reaction was the lowest, which was 12.5 kcal/mol. Analysis of the values found that OH-addition and F-substitution, the substitution of O for F and addition at the C14 site, as well as the cleavage reactions of C6-F/C7-C16/C17-C18/C18-N/C19-N/C20-N are the main pathways of photodegradation of CIT.
西酞普兰（CIT）是一种常用于治疗抑郁症的处方药物。然而，CIT 的光降解机制尚未得到充分分析。因此，通过密度泛函理论和含时密度泛函理论研究了 CIT 在水中的光降解过程。计算结果表明，在间接光降解过程中，CIT 与·OH 的间接光降解通过 OH-加成和 F-取代发生。C10 位的最小活化能为 0.4 kcal/mol。所有的 OH-加成和 F-取代反应都是放热的。O 与 CIT 的反应包括 O 对 F 的取代和 C14 位的加成反应。该过程的 值为 1.7 kcal/mol，是 O 与 CIT 反应所需的最低活化能。直接光降解过程涉及 C-C/C-N/C-F 键的断裂。在 CIT 的直接光降解中，C7-C16 断裂反应的活化能最低，为 12.5 kcal/mol。 值分析表明，OH-加成和 F-取代、O 对 F 的取代和 C14 位的加成以及 C6-F/C7-C16/C17-C18/C18-N/C19-N/C20-N 的断裂反应是 CIT 光降解的主要途径。
