A first example of low-energy blue-lightmediated formal Doyle−Kirmse reaction for gem-difluoroallylation of aryl diazoesters has been developed. A variety of highly functionalized gem-difluoroallyl containing esters bearing transformable sulfur and bromine groups were efficiently assembled with broad substrate scope under mild, catalyst-free, and additive-free conditions. The reaction represents a practical and environmentally friendly approach for C−CF 2 bond formation based on rearrangement strategy, which will find potential applications among drug discovery and development.

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PurposeAs a promising photodynamic therapy (PDT) agent, Al(III) phthalocyanine chloride tetrasulfonic acid (AlPcS4) provides deep penetration into tissue, high quantum yields, good photostability, and low photobleaching. However, its low delivery efficiency and high binding affinity to serum albumin cause its low penetration into cancer cells, further limiting its PDT effect on gastric cancer. In order to improve AlPcS4/PDT effect, the AlPcS4 delivery sys tems with different drug carriers were synthesized and investigated.Materials and methodsGold nanorods, cationic liposomes, and Pluronic® F127 nanomicellars were used to formulate the AlPcS4 delivery systems. The anticancer effect was evaluated by CCK-8 assay and colony formation assay. The delivery efficiency of AlPcS4 and the binding affinity to serum proteins were determined by fluorescence intensity assay. The apoptosis and necrosis ability, reactive oxygen species and singlet oxygen generation, mitochondrial transmembrane potential and ([Ca2+]i) concentration were further measured to evaluate the mechanism of cell death.ResultsThe series of synthesized AlPcS4 delivery systems with different drug carriers improve the limited PDT effect in varying degrees. In contrast, AlPcS4 complex with gold nanorods has significant anticancer effects because gold nanorods are not only suitable for AlPcS4 delivery, but also exhibit enhanced singlet oxygen generation effect and photothermal effect to induce cell death directly. Moreover, AlPcS4 complex with cationic liposomes shows the potent inhibition effect because of its optimal AlPcS4 delivery efficiency and ability to block serum albumin. In addition, AlPcS4 complex with Pluronic F127 exhibits inferior PDT effect but presents lower cytotoxicity, slower dissociation rate, and longer retention time of incorporated drugs; thus, F127–AlPcS4 is used for prolonged gastric cancer therapy.ConclusionThe described AlPcS4 drug delivery systems provide promising agents for gastric cancer therapy.

The first example of phenanthroline‐tBuONa promoted intramolecular C−H arylation of 1,5‐diaryl‐1,2,3‐triazoles without the involvement of transition metals has been developed. Various fused 1,5‐disubstituted‐1,2,3‐triazoles of triazolophenanthridines were prepared with excellent yields and high site‐selectivity via simple and efficient intramolecular cyclization by using the 1,10‐phenanthroline‐tBuONa reaction system.

An efficient method for the synthesis of triazole-fused phenanthridines from 1,5-diaryl-1,2,3-triazoles under palladium catalysis has been developed. The reaction proceeds through Pd-catalyzed intramolecular phenyl C–H activation of 1,5-diaryl-1,2,3-triazoles. This method provides a concise and efficient pathway to construct triazolo[1,5-f]phenanthridine derivatives in excellent yields.