Tailoring the Performance of 19F-Labeled Probes via Dynamic Covalent Chemistry for Improved Chiral Discrimination.

This work presents a novel strategy for postmodifying probes using dynamic covalent chemistry. Leveraging reversible interactions between boronic acid and diols, we obtained a panel of 19F-labeled probes with distinct resolving abilities. This approach enables rapid identification of probes with satisfactory performance, streamlining synthesis, and enhancing efficiency in chiral analysis. Our findings demonstrate an exceptional ability to differentiate compounds with distal chirality and challenging aliphatic amines. The postmodified probes also exhibit accuracy and reliability in determining enantiomeric excess, promising advancements in enantio-analysis techniques and chiral discrimination.

Chiral Discrimination of Acyclic Secondary Amines by 19F NMR.

Chiral aliphatic amine compounds exhibit a range of physiological activities, making them highly sought-after in the pharmaceutical industry and biological research. One notable obstacle in studying these compounds stems from the pronounced steric hindrance surrounding the nitrogen atom. This characteristic often leads to a weak affinity of acyclic secondary amines for molecular probes, making their chiral discrimination intricate. In response to this challenge, our research has unveiled a novel 19F-labeled probe adept at recognizing and distinguishing between enantiomers of these acyclic secondary amines. By strategically incorporating a single fluorine atom as the 19F label, we have managed to diminish the steric hindrance at the binding site. This alteration bolsters the probe's affinity toward bulkier analytes. As a testament to its effectiveness, we have successfully employed our probe in the chiral analysis of relevant pharmaceuticals, accurately determining their enantiocomposition.

Heavy Atom-Free, Mitochondria-Targeted, and Activatable Photosensitizers for Photodynamic Therapy with Real-Time In-Situ Therapeutic Monitoring.

Based on spin-orbit charge transfer intersystem crossing mechanism, two heavy-atom-free photosensitizers (PSs) BDP1/BDP2 with absorption maxima at 506 nm/660 nm were constructed for photodynamic therapy (PDT). The long triplet state lifetimes and large singlet oxygen quantum yields, coupled with the mitochondria-targeted feature, made them highly phototoxic toward cancer cells. Moreover, the PDT-promoted cell apoptosis could be monitored by an obvious fluorescence off-on response of the two PSs due to the concomitant activation of extensive mitophagy, thus facilitating timely therapeutic feedback to avoid under- or over-treatment. Importantly, such design allows the activatable PSs Glu-BDP1/Glu-BDP2 to be fabricated by attaching γ-glutamyl, a substrate of γ-glutamyltranspeptidase, to the alkoxyaniline unit of BDP1/BDP2, and their ability in either selectively killing cancer cells over normal cells or in ablating implanted tumour without damage to healthy tissue was demonstrated.