Seo Dayeong, Kwon Seongyeon, Yoon Gahye, Son Taeil, Won Changhyeon, Singh Neetu, Kim Dongwook, Baek Yunjung
Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.
Center for Catalytic Hydrocarbon Functionalizations, Institute for Basic Science, Daejeon, Republic of Korea.
Nat Commun. 2025 Apr 15;16(1):3561. doi: 10.1038/s41467-025-58957-2.
Inspired by the prominent redox and optical properties of natural flavins, synthetic flavins have found broad applications in organic, photochemical, and biochemical research. Tailoring these properties of flavins, however, remains a challenge. In this work, we present three pentacyclic flavins (C-PF, O-PF, and S-PF) that leverage a strategic molecular design to modify the flavin's electronic structure. Notably, the oxygen- and sulfur-linked pentacyclic flavins (O-PF and S-PF) exhibit deep-red and NIR emission, respectively, driven by enhanced π-conjugation, substituent effects, and charge separation upon excitation. These heteroatom-incorporated pentacyclic flavins exhibit unusual quasi-reversible oxidation, expanding both optical and redox limits of synthetic flavins. Comprehensive spectroscopic, structural, and computational analyses reveal how heteroatom incorporation within this five-ring-fused system unlocks redox and optical properties of flavin-derived chromophores.
受天然黄素突出的氧化还原和光学性质的启发，合成黄素在有机、光化学和生物化学研究中得到了广泛应用。然而，调整黄素的这些性质仍然是一个挑战。在这项工作中，我们展示了三种五环黄素（C-PF、O-PF和S-PF），它们利用策略性分子设计来改变黄素的电子结构。值得注意的是，氧连接和硫连接的五环黄素（O-PF和S-PF）分别表现出深红色和近红外发射，这是由激发时增强的π共轭、取代基效应和电荷分离驱动的。这些含有杂原子的五环黄素表现出不同寻常的准可逆氧化，扩展了合成黄素的光学和氧化还原极限。全面的光谱、结构和计算分析揭示了在这个五环稠合系统中引入杂原子是如何解锁黄素衍生发色团的氧化还原和光学性质的。
