Singlet oxygen is the key element for photodynamic therapy. In this paper, six novel distyryl-BODIPY compounds were synthesized and investigated in detail to fully evaluate their photophysical/chemistry characteristics. Specially, the singlet oxygen (¹O₂) quantum yield of compounds 2 and 4 each bearing two bromine atoms in their skeleton revealed the position effect of heavy atom for ¹O₂ production. The ¹O₂ quantum yield of 4, which was brominated at 2/6 position of BODIPY skeleton, was much higher than that of compound 2, brominated at styryl group with a long distance toward BODIPY core. Importantly, theoretical calculations were carried out to elaborate the essential reason for the difference of 2 and 4 by investigating intersystem crossing rate.

中文翻译：

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Distyryl-BODIPY衍生物的光物理/化学性质：实验和密度泛函理论研究

单线态氧是光动力疗法的关键元素。在本文中，合成并详细研究了六个新颖的二苯乙烯基-BODIPY化合物，以全面评估它们的光物理/化学特性。特别地，化合物2和4的骨架中均带有两个溴原子的化合物2和4的单重态氧（¹ O ₂）量子产率显示出重原子对¹ O ₂产生的位置效应。在BODIPY骨架的2/6位溴化的4的¹ O ₂量子产率比化合物2的高得多。，在苯乙烯基上溴化，与BODIPY核之间的距离较远。重要的是，通过研究系统间交叉速率，进行了理论计算以阐明2和4差异的根本原因。