Kawabata Kohei, Masumoto Misaki, Inagaki Masanori, Nishi Hiroyuki
Faculty of Pharmacy, Yasuda Women's University, Yasuhigashi 6-13-1, Asaminami-Ku, Hiroshima, 731-0153, Japan.
Anal Sci. 2023 Nov;39(11):1813-1821. doi: 10.1007/s44211-023-00424-3. Epub 2023 Sep 7.
Photodegradation is widely known as a changer of both the quality and the quantity of several chemical compounds. In this study, we sought to examine the photochemical behavior of triprolidine (TRP), which is a member of the first-generation antihistamine and utilized for a relief of an allergic conditions, in an aqueous media. There are no reports focused on its potential photoproducts and photodegradation pathways in detail to the best of our knowledge. TRP photodegradation induced by ultraviolet light (UV) irradiation was monitored utilizing high-performance liquid chromatography (HPLC), and structural elucidation of the TRP photoproduct was performed by electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) and nuclear magnetic resonance (NMR). Finally, the mechanism of TRP photodegradation was speculated based on the identified photoproduct. TRP was photodegraded dependent on the irradiation time of UV in proportion to the generation of one TRP photoproduct (TRP-P). Structural determination by LC-ESI-MS/MS and NMR clarified that TRP-P was the geometrical isomer of TRP, which was formed by the cis-trans conversion of double bond. UV irradiation experiment for TRP-P revealed the conversion from it to TRP. It is clarified that cis-trans conversion between TRP and TRP-P is photo-equilibrium reaction and TRP-P is predominant under the condition as this experiment. Toxicological potencies of TRP and TRP-P might not be observed by ProTox-II in silico toxicity evaluation. This is the first study evaluating the photochemical behavior of TRP.
光降解作为多种化合物质量和数量的改变因素广为人知。在本研究中，我们试图研究曲普利啶（TRP）在水介质中的光化学行为，曲普利啶是第一代抗组胺药的一种，用于缓解过敏症状。据我们所知，尚无详细聚焦于其潜在光产物和光降解途径的报道。利用高效液相色谱法（HPLC）监测紫外线（UV）照射诱导的TRP光降解，并通过电喷雾电离串联质谱法（LC-ESI-MS/MS）和核磁共振（NMR）对TRP光产物进行结构解析。最后，基于鉴定出的光产物推测TRP的光降解机制。TRP的光降解与UV照射时间相关，与一种TRP光产物（TRP-P）的生成成比例。通过LC-ESI-MS/MS和NMR进行的结构测定表明，TRP-P是TRP的几何异构体，由双键的顺反转化形成。对TRP-P的UV照射实验揭示了其向TRP的转化。明确了TRP与TRP-P之间的顺反转化是光平衡反应，在本实验条件下TRP-P占主导。在ProTox-II计算机模拟毒性评估中未观察到TRP和TRP-P的毒理学效力。这是第一项评估TRP光化学行为的研究。
