Engineering of an electronically decoupled difluoroindacene-pyrene dyad possessing high affinity for DNA

A highly fluorescent dual-dye, comprising 4,4-difluoro-8-(aryl)1,3,5,7-tetramethy I -2,6-diethyl-4-bora-3a,4a-diaza-s-indacene and 1-pyrenyl fragments linked orthogonally at the pseudo-meso position, displays a wide choice of excitation wavelengths due to intramolecular energy transfer and undergoes efficient fluorescence quenching when bound to double-stranded DNA.