Work

Expanding the chemical space of flavins with pentacyclic architecture

Year: 2025

Type: article

Abstract: 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. Flavins have redox and optical properties applicable to organic, photochemical, and biochemical research, though tailoring these properties remain challenging. Here, the authors report several flavins exhibiting deep-red and NIR emission, and quasi-reversible oxidation.

Source: Nature Communications

DOI: 10.1038/s41467-025-58957-2