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In view of the longevity and innate immune escape of red blood cells, this study designed the red blood cell membrane-coated paclitaxel nanosuspension [RBC-(PTX)NS] and investigated its physicochemical properties and antitumor effect in vitro. Paclitaxel nanosuspension [(PTX)NS] was prepared by ultrasonic precipitation and then RBC-(PTX)NS by ultrasonic coating. The formulation of(PTX)NS was optimized with Box-Behnken method and indexes of particle diameter, zeta potential, and stability. The morphology, particle diameter, stability, in vitro dissolution, and antitumor effect of(PTX)NS and RBC-(PTX)NS were characterized. The results showed that the particle diameter and zeta potential were(129.38±0.92) nm and(-22.41±0.48) mV, respectively, for the optimized(PTX)NS, while(142.5±0.68) nm and(-29.85±0.53) mV, respectively, for RBC-(PTX)NS. Under the transmission electron microscope,(PTX)NS was spherical and RBC-(PTX)NS had obvious core-shell structure. RBC-(PTX)NS remained stable for 5 days at 4 ℃. The in vitro dissolution test demonstrated that the cumulative release rate of RBC-(PTX)NS reached 79% within 20 min, which was significantly higher than that(25%) of(PTX)NS(Plt;0.05). As evidenced by MTT assay, RBC-(PTX)NS highly inhibited the proliferation of HepG2 cells in a dose-dependent manner. The cell membrane-coated nano-preparation preparation method is simple and reproducible. It improves the solubility of PTX and endows RBC-(PTX)NS with higher stability and stronger cytotoxicity. Thus, it is a new method for the delivery of PTX via nanocrystallization.

含氮芳环作为液晶分子的极性介晶基团，能有效增大分子的偶极矩和分子间的作用力，有利于形成近晶相液晶态，提高分子的介电各向异性，降低液晶的驱动电压。本文试图以嘧啶、吡啶为中心结构单元来增大化合物的偶极矩，设计合成了二个系列含嘧啶、吡啶的双芳环液晶化合物nOBMm、nOBPm系列共7个化合物；它们都经过IR、1H-NMR、13C-NMR和MS光谱对其分子结构鉴定，经过差热分析仪（DSC）和偏光显微镜（POM）对其液晶性能进行检测。实验结果表明，所有化合物的分子结构均正确，具有较宽的近晶相态，可作为铁电液晶和高分子聚合物分散液晶材料配方组分，为进一步研究低能耗铁电液晶和聚合物分散液晶材料提供了实验素材。

The hydrosilylation of alkenes with triethoxysilane has been achieved at 120 °C in the presence of 0.01 mol% of thioether-functionalized MCM-41 anchored rhodium complex, affording the corresponding addition products in 68–91% yields. This supported rhodium complex can be reused several times without noticeable loss of activity. Our system not only solves the basic problems of catalyst separation and recovery, but also avoids the use of phosphine ligands.

1,4-Dienyl selenides can be stereoselectively synthesized in one pot under mild conditions in good yields by the palladium-catalyzed hydrostannylation of acetylenic selenides, followed by Stille coupling with allylic bromides.

( E )-α-Iodovinyl sulfones 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol% of Pd(PPh 3 ) 4 and 10 mol% of CuI to stereospecifically afford the corresponding ( Z )-2-sulfonyl-substituted 1,3-enynes 3 in high yields.

1,4-Dienyl selenides can be stereoselectively synthesized in one pot under mild conditions in good yields by the palladium-catalyzed hydrostannylation of acetylenic selenides, followed by Stille coupling with allylic bromides.

( E )-α-Iodovinyl sulfones 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol% of Pd(PPh 3 ) 4 and 10 mol% of CuI to stereospecifically afford the corresponding ( Z )-2-sulfonyl-substituted 1,3-enynes 3 in high yields.