Photophysical properties of the synthesized compounds.

Compounds	λ abs a [nm]	ε × 10−3a [M−1 cm−1]	λ em a [nm]	Stokes shift [nm]	Φ f b (%)	Φ Δ c
BODIPY d	502	120.00	508	6	70.0	≈0
PY-BOD	568	107.09	585	17	9.82	0.52
PH-BOD	564	111.60	576	12	18.83	0.69
MeO-BOD	564	115.78	579	15	17.11	0.85
DMA-BOD	562	96.99	577	15	2.50	0.04

^aIn toluene (5.0 × 10⁻⁶ M).

^bFluorescence quantum yield estimated relative to rhodamine 101 as the standard (Φ_f = 1.0 in methanol).

^cSinglet oxygen quantum yield was determined with respect to rose bengal (Φ_Δ (RB) = 0.54 in ACN).

^dLiterature value.¹⁹