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Comprehensive Summary: A visible‐light‐induced tandem radical intramolecular cyclization/arylation of quinoxalin‐2(1H)‐ones with bromodifluoroacetamides is described. This protocol allows efficient access to a variety of valuable α,α‐difluoro‐γ‐lactam‐fused quinoxalin‐2(1H)‐ones in moderate to good yields under metal‐free, mild and redox neutral reaction conditions. This strategy is tolerant of various functional groups and a broad range of substrates. The mechanism experiments suggested an involvement of 5‐exo‐trig cyclization and a radical process in this transformation. [ABSTRACT FROM AUTHOR]

This work reports the photocatalytic application of an anthraquinone‐containing polymeric photosensitizer (AQ‐PHEMA) in the visible light‐induced cross‐dehydrogenative‐coupling of N‐aryl tetrahydroisoquinolines with several nucleophiles, including nitromethane, 1‐methyl‐2‐alkyl ketone and dialkyl (aryl) phosphine oxide. The results revealed that the reaction could be catalyzed by AQ‐PHEMA efficiently to afford a series of 1‐substituted‐2‐aryl‐1,2,3,4‐tetrahydroisoquinolines in good to excellent yields with nice substrate tolerance under aerobic conditions at room temperature. The practical application potential was also showcased by a gram‐scale synthesis. More importantly, the utilization of AQ‐PHEMA as a heterogeneous photosensitizer also showed nice recyclability and reusability of the catalyst, whereas AQ‐PHEMA can be easily separated and reused for at least 8 times without significant loss of photocatalytic activity. [ABSTRACT FROM AUTHOR]

A visible‐light‐induced site selective C−H alkylation of heterocyclic N‐oxides with N‐hydroxyphthalimide esters was developed using Eosin Y as the photocatalyst in the presence of Cs2CO3 under redox‐neutral and mild conditions. Using N‐hydroxyphthalimide esters as the radical precursors, quinoline and pyridine N‐oxides were readily coupled with a wide range of primary, secondary, and tertiary radicals to afford the desired alkylated heterocyclic N‐oxides in moderated to excellent yields. Importantly, this reaction protocol also successfully demonstrated its applications for the construction of glycosyl or bioactive natural dehydroabietic acid containing heterocyclic N‐oxides, as well as the pharmaceutical and agrochemical active alkylated quinine‐based functional molecules (potential antimalarial drug). [ABSTRACT FROM AUTHOR]

Summary: Aims: The objective of this study was to analyze the efficacy of polypyrrole/polylactic acid (PPy/PLA) nanofibrous scaffold cotransplanted with bone marrow stromal cells (BMSCs) in promoting the functional recovery in a rat spinal cord injury (SCI). Methods: Female Sprague‐Dawley rats were randomly divided into three groups (n = 18/group): control group, PPy/PLA group, and PPy/PLA/BMSCs group. The SCI was induced in all rats. Consequently, rats in PPy/PLA/BMSCs group were transplanted with 1 × 105 BMSCs after implantation of PPy/PLA, while those in the PPy/PLA group were implanted with PPy/PLA only; no implantation was performed in the control group. Six weeks after surgery, immunofluorescence microscopy, electron microscope, and polymerase chain reaction (PCR) techniques were performed to assess the changes in the injured spinal cord tissues. Results: Electrophysiology and locomotor function testing suggested that PPy/PLA nanofibrous scaffold cotransplanted with BMSCs could promote the functional recovery of the spinal cord. Six weeks after the operation, lower amount of scar tissue was found in the PPy/PLA group compared with the control group. Abundant neurofilament (NF) and neuron‐specific marker (NeuN) positive staining, and myelin formations were detected in the injured area. In addition, the transplantation of BMSCs not only improved the efficacy of PPy/PLA but also managed to survive well and was differentiated into neural and neuroglial cells. Conclusions: The implantation of PPy/PLA nanofibrous scaffold and BMSCs has a great potential to restore the electrical conduction and to promote functional recovery by inhibiting the scar tissue formation, promoting axon regeneration, and bridging the gap lesion. [ABSTRACT FROM AUTHOR]