AIE Fluorescent Probes Constructed by Introducing Acceptor-Derived Microbial Metabolite Staurosporine

The aggregation-caused quenching (ACQ) phenomenon limits the bioimaging application of traditional fluorescent probes. To address this, we developed a novel strategy to convert ACQ-type bioactive Staurosporine analogues into aggregation-induced emission (AIE) luminogens by constructing a donor-acceptor system via the introduction of cyano units as strong electron-withdrawing groups. First, we successfully developed a novel fluorescent scaffold based on the skeleton of Staurosporine, which is a kind of microbial secondary metabolite. Next, we synthesized three derivatives (STY1-3) by introducing a new rotor via one-step structural modification. These three compounds exhibited tunable AIE fluorescence and retained significant bioactivity. Cellular imaging demonstrated their capacity to outline cell contours with low background interference, while cytotoxicity assays revealed potent antitumor activity against NCI-N87 and MCF-7 cell lines. This work provides a design method for developing bioactive AIE probes from natural ACQ scaffolds.