Ural Federal University, 19 Mira Str., Yekaterinburg, 620002, Russia.
M. N. Mikheev Institute of Metal Physics, Ural Branch of Russian Academy of Science, 18 S. Kovalevskaya Str., Yekaterinburg, 620219, Russia.
Org Biomol Chem. 2021 Nov 25;19(45):9880-9896. doi: 10.1039/d1ob01801a.
New 2-aryl-1,2,3-triazolopyrimidines were designed, synthesized, and characterized. Their optical properties were thoroughly studied in the solid phase, in solution and in a biological environment. Density Functional Theory (DFT) based calculations were performed, including the molecular geometry optimization for both the ground state and the first singlet excited state, the prediction of the UV-Vis absorption and fluorescence spectra, the determination of the molecular electrostatic properties and the solvent effect on the optical properties. The emission intensity was revealed to increase in time upon irradiation. Mass spectrometric research, quantum mechanical calculations, and analysis of literature data suggested a possible photo-transformation pathway through the homolytic cleavage of one of the C-Cl bonds upon irradiation with UV light. The structure of the active intermediate was identified by the series of mass spectrometry experiments and synthesis of putative transformation products. The kinetic parameters measured in different solvents allowed estimating the rate of these photo-transformations. Biological experiments demonstrated that 2-aryl-1,2,3-triazolopyrimidines penetrate cells and selectively accumulate in the cell membrane and the Golgi complex and endoplasmic reticulum. Their unique properties pave the way for new possible applications of fluorescent 8-azapurines in biology and medicine.
新的 2-芳基-1,2,3-三唑并嘧啶被设计、合成并进行了表征。它们的光学性质在固相、溶液和生物环境中进行了深入研究。进行了基于密度泛函理论（DFT）的计算，包括基态和第一单重激发态的分子几何优化、预测紫外-可见吸收和荧光光谱、确定分子静电性质以及溶剂对光学性质的影响。结果表明，在照射下，发光强度随时间增加。质谱研究、量子力学计算和文献数据的分析表明，可能通过在紫外光照射下均裂一个 C-Cl 键发生光转化。通过一系列质谱实验和假定转化产物的合成，确定了活性中间体的结构。在不同溶剂中测量的动力学参数允许估计这些光转化的速率。生物实验表明，2-芳基-1,2,3-三唑并嘧啶能够穿透细胞，并选择性地在细胞膜、高尔基体和内质网中积累。它们独特的性质为荧光 8-氮杂嘌呤在生物学和医学中的新的潜在应用铺平了道路。
