Abstract：
Novel fluorescent nucleic acid base analogues (FBAs) with improved optical properties are needed in a variety of biological applications. 2-Amino-6-chloro-8-vinylpurine (2A6Cl8VP) is structural analogue of two existing highly fluorescent FBAs, 2-aminopurine (2AP) and 8-vinyladenine (8VA), and can therefore be expected to have similar base pairing as well as better optical properties compared to its counterparts. In order to determine the absorption and fluorescence properties of 2A6Cl8VP, as a first step, we used TD-DFT calculations and the polarizable continuum model for simulating the solvents and computationally predicted absorption and fluorescence maxima. To test the computational predictions, we also synthesized 2A6Cl8VP and measured its UV/vis absorbance, fluorescence emission, and fluorescence lifetime. The computationally predicted absorbance and fluorescence maxima of 2A6Cl8VP are in reasonable agreement to the experimental values and are significantly redshifted compared to 2AP and 8VA, allowing for its specific excitation. The fluorescence quantum yield of 2A6Cl8VP, however, is significantly lower than those of 2AP and 8VA. Overall, 2A6Cl8VP is a novel fluorescent nucleobase analogue, which can be useful in studying structural, biophysical, and biochemical applications.
摘要：
在多种生物应用中需要具有改进的光学性质的新型荧光核酸碱基类似物(FBA)。2-氨基-6-氯-8-乙烯基嘌呤（2A6Cl8VP）是两种现有的高荧光FBA的结构类似物，2-氨基嘌呤（2AP）和8-乙烯基腺嘌呤（8VA），并且因此可以预期与其对应物相比具有相似的碱基配对以及更好的光学性质。为了测定2A6Cl8VP的吸收和荧光性质,作为第一步,我们使用TD-DFT计算和可极化连续模型来模拟溶剂，并通过计算预测吸收和荧光最大值。为了测试计算预测，我们还合成了2A6Cl8VP并测量了其紫外/可见吸光度，荧光发射，和荧光寿命。2A6Cl8VP的计算预测吸光度和荧光最大值与实验值合理一致，与2AP和8VA相比显著红移，允许其特定的激励。2A6Cl8VP的荧光量子产率，然而,显著低于2AP和8VA。总的来说,2A6Cl8VP是一种新型的荧光核碱基类似物，这对研究结构很有用，生物物理，和生化应用。
