Photophysical Characteristics of Polarity‐Sensitive and Lipid Droplet‐Specific Phenylbenzothiadiazoles

In this study, we present a series of solvatochromic phenylbenzothiadiazoles that display dual emission from the locally excited (LE) and intramolecular charge transfer (ICT) states. The donor-acceptor derivatives are highly sensitive to polarity changes, which can be monitored by differences in efficiency, spectroscopic shifts variations LE/ICT ratio. One compounds series, containing thiomethyl substituent, emerged as an excellent blue emitting stain for intracellular lipid droplets, biomarker various types cancer. addition, non-emissive nitro derivative becomes fluorescent upon bioreduction hypoxic cancer cells accumulates droplets with high signal-to-background