Nanoparticles (NPs) have proven to be effective drug carriers in diagnosis and therapy of cancer. But, they faced a contradictory issue that NPs with large size appear weak tumor penetration, meanwhile small size resulted in poor tumor retention. Herein, we fabricated doxorubicin conjugated carbon dots (CDs-DOX) and indocyanine green (ICG)-loaded liposomes (ICG-LPs) named CDs-ICG-LPs using a modified reverse phase evaporation process, and with high incorporation in the aqueous core. The CDs-ICG-LPs exhibited good monodispersity, excellent fluorescence/size stability, and consistent spectra characteristics compared with free ICG or DOX. Moreover, the CDs-ICG-LPs showed higher temperature response, faster DOX release under laser irradiation. In the meantime, the fluorescence of DOX and ICG in CDs-ICG-LPs was also visualized for the process of subcellular location in vitro . In comparison with chemo or photothermal treatment alone, the combined treatment of CDs-ICG-LPs with laser irradiation synergistically induced the apoptosis and death of DOX-sensitive HepG2 cells. In vivo antitumor activities demonstrated CDs-ICG-LPs could reach higher antitumor activity compared with CDs-DOX and ICG-LPs for H22 tumor cells, and suppressed H22 tumor growth in vivo . Notably, no systemic toxicity occurrence was observed after repeated dose of CDs-ICG-LPs with laser irradiation. Hence, the well-defined CDs-ICG-LPs exhibited great potential in targeting cancer imaging and chemo-photothermal therapy.

To make further researches on the structure-activity relationships (SARs) of our previous synthesized neonicotinoid compounds, a new series of nitenpyam analogues with flexible ester arm were synthesized. Preliminary bioassays indicated that all of our newly designed nitenpyam analogues exhibited good insecticidal activity at 100 mg/L, while analogues 4c and 4d afforded the best in vitro activity, and both of them had 100% mortality at 20 mg/L. The SAR studies suggested that their insecticidal potency was dual-controlled by the length of the ester arm and the size of the ester group. In addition, the molecular docking simulations revealed that the structural uniqueness of these analogues may lead to a unique molecular recognition and binding mode, which explained the SARs observed in vitro, and shed light on the novel insecticidal mechanism of these novel nitenpyam analogues.

A novel series of cis-nitenpyram analogues (2a-2p) were designed and prepared by introducing the 1,4-dihydropyridine, with their cis-configuration confirmed by X-ray diffraction. Preliminary bioassays showed that most compounds exhibited good insecticidal activities at 20 mg/L against Aphis medicagini, and analogues 2a and 2d afforded the best activity, and both of them had 100% mortality at 4 mg/L. In addition, molecular docking studies were also performed to model the ligand-receptor complexes, and the results explained the structure-activity relationships observed in vitro, which may provide some useful information for future design of new insecticides.

The aromatic dimers play a significant role in many aspects. Herein, we report a simple palladium-carbon catalyst that is highly effective for the dimerization of brominated aromatic compounds under mild conditions using abundant brominated aromatic compounds, bis(pinacolate)diboron and potassium acetate by a ‘one-pot’ method. This process, which we believe proceeds via a Suzuki–Miyaura cross-coupling reaction mechanism, allows access to a variety of aromatic compounds under mild reaction conditions and has a good functional group tolerance with moderate to high yields.

No abstract