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Despite the various attractive properties of γ-pyrones, there are still some deficiencies in their synthetic approaches such as lower atom economy, multistep processes, and prefunctionalization of the reagents. In this work, an efficient and simple (CF

Tumor-targeted ligand modification and nanosized coloaded drug delivery systems are promising for cancer therapy. In this study, we showed that coix seed oil and tripterine coloaded microemulsions with a transferrin modification (Tf-CT-MEs) could improve the treatment of cervical cancer. Tf-CT-MEs exhibited good stability in serum and a notably synergistic antiproliferation effect. In the HeLa xenograft tumor-bearing mouse model, Tf-CT-MEs accumulated at tumor sites and penetrated deeply in tumor tissues. Tf-CT-MEs had superior anticancer efficacy in vivo, which greatly slowed the growth of tumors (***p < 0.001 vs saline). We also found that Tf-CT-MEs inhibited tumor cell proliferation, enhanced antiangiogenesis, and induced apoptosis by regulating bax/bcl-2 and the activating caspase-3 pathway. Tf-CT-MEs decreased by 27.7, 26.9, 61.2, and 42.5% of concentrations of TGF-β1, CCL2, TNF-α, and IL-6 in serum, respectively. In addition, Tf-CT-MEs showed little toxicity in vital organs. These results were due to the improved drug delivery efficiency. Collectively, Tf-CT-MEs enhance tumor-targeting, facilitate deep penetration of drugs, and have promising potential as an efficient treatment for cervical cancer.

The application of tandem catalysis is rarely investigated in degrading organic pollutants in the environment. Herein, a tandem catalyst on single platinum (Pt) nanoparticles (Pt0 NPs) is prepared for the sequential degradation of formaldehyde (HCHO) to carbon dioxide gas [CO2(g)] at room temperature. The synthesis approach includes coating of uniform Pt NPs on SrBi2Ta2O9 platelets using a photoreduction process, followed by calcination of the sample in the atmosphere to tune partial transformation of Pt0 atoms to Pt2+ ions in the tandem catalyst. The conversion of HCHO to CO2(g) is monitored by in situ Fourier transform infrared spectroscopy, which shows first conversion of HCHO to CO32- ions onto Pt0 active sites and subsequently the conversion of CO32- ions to CO2(g) by neighboring Pt2+ species of the catalyst. The later process with Pt2+ species does not allow CO32- poisoning of the catalyst. The enhanced activity of the prepared tandem catalyst to oxidize HCHO is maintained continuously for 680 min. Comparatively, the catalyst without Pt2+ shows activity for only 40 min. Additionally, the tandem catalyst presented herein performs better than the Pt/titanium dioxide (TiO2) catalyst to degrade HCHO. Overall, the tandem catalyst may be applied to degrade organic pollutants efficiently.

Surface-induced crystallization of an isotropic Bi nanodroplet in three distinct steps was recorded at atomic resolution by in situ high resolution transmission electron microscopy. First, formation of a crystalline nucleus at the edge of the nanodroplet is induced by the liquid-state surface faceting, which initiates the formation of a prefreezing state with a distorted structure. Then, a periodic line pattern of the atomic columns with a periodicity of 0.49 nm that is relative to the interlayer spacing of the Bi crystal along the ⟨112⟩* direction (one-dimensional ordered structure) was formed by structure relaxation of the prefreezing nanoparticle, followed by a concerted growth and ordering process. Finally, the crystallization from the periodic structure was carried out by atom/atom interactions within and between the atomic layers to form the covalent Bi–Bi bonds that have the same arrangement as in the Bi crystal (crystallization along the ⟨110⟩ direction). Motivated by the experimental observation...

The aim of this study is to demonstrate the enhanced therapeutic efficacy of anticancer drugs on drug-resistant breast cancer using multicomponent microemulsions (ECG-MEs) as an oral delivery system. The etoposide-loaded ECG-MEs were composed of coix seed oil and ginsenoside Rh2 (G-Rh2), both of which possess not only the synergistic antitumor effect with etoposide, but also have excipient-like properties. Orally administrated ECG-MEs were demonstrated to be able to accumulate at the tumor site following crossing the intestines as intact vehicles into the blood circulation. The spatiotemporal controlled release characteristics of ECG-MEs brought about the efficient P-gp inhibition by the initially released G-Rh2 and the increased intracellular accumulation of the sequentially released etoposide. The combination antitumor activity of etoposide, G-Rh2 and coix seed oil using ECG-MEs was verified on the xenograft drug-resistant breast tumor mouse models. In addition, the safety evaluation studies indicated that treatment with ECG-MEs did not cause any significant toxicity in vivo. These findings suggest that ECG-MEs as an oral formulation may offer a promising strategy to treat the drug-resistant breast cancer.

A new and efficient metal-free tandem acylation/cyclization of alkynoates with aldehydes was developed for the synthesis of 3-acyl-4-arylcoumarins. The reaction was achieved by the addition of acyl radical to alkynes and a C-H bond functionalization to form two new C-C bonds simultaneously.

A novel Pd(II)-catalyzed dehydrogenative cross-coupling reaction between coumarins and H-phosphonates has been developed to give the corresponding 3-phosphonated products in moderate to good yields with high selectivity.