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121.
A practical and efficient synthesis of phosphatidylinositol pentam annoside (PIM5) was achieved based on a five-component one-pot sequential glycosylation protocol with exclusive regio- and stereo-selectivity. 相似文献
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Chromatographia - A novel method for the rapid simultaneous determination of multiple fungicide residues in tobacco was established using ultra-performance liquid chromatography–tandem mass... 相似文献
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Hang Ma Yang He Ruo-Feng Huang Xiao-Hui Zhang Jing Pan Jia-Qiang Li Chao He Xue-Ge Ling Xuan-Lun Wang Yan Xiong 《中国化学快报》2014,25(10):1327-1330
Under neat conditions,an efficient method for synthesis of imidoesters has been developed using cyanatobenzenes and dicarbonyl compounds.Nucleophilic addition spontaneously occurred between the two kinds of materials at room temperature with yields of up to 90%.A mechanism directed towards to the imidoester formation has been proposed. 相似文献
125.
Bing Wang Chi Ma Zuo-Chun Xiong Cheng-Dong Xiong Quan-Hua Zhou Dong-Liang Chen 《中国化学快报》2013,24(5):392-396
In order to expand the application of poly(p-dioxanone) or PPDO in biomedical area,a series of novel copolymers were synthesized successfully by one-step,melted copolymerization of p-dioxanone(PDO) and L-phenylalanine N-carboxyanhydride(L-Phe-NCA) monomers.With the in-feed molar ratio of L-PheNCA /PDO equal to 1/20,the conversions of the two kinds of monomers were calculated from ~1H NMR. The average molecular weight and polydispersity of the copolymer increase with the increasing reaction time and catalyst concentration.However,the conversions of the two kinds of monomers did not change with the reaction conditions.A three-step mechanism is presented and proved by high resolution ~1H NMR and IR spectrums. 相似文献
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Li Zhao Qiangjun Ling Xiong Liu Chaodong Hang Qiuxia Zhao Fangfei Liu Haibin Gu 《应用有机金属化学》2018,32(2)
Owing to their unique broken symmetry, amphiphilic Janus dendrimers and dendons provide fascinating properties for material, biological, pharmaceutical and biomedical applications. The integration of various organometallic moieties into these macromolecules will further offer the opportunity to form complex and intelligent architectures and materials. Here, we report a novel, simple and multifunctional Janus dendron containing redox‐reversible hydrophobic ferrocene (Fc) unit, complexing‐effective 1,2,3‐triazole ligand and biocompatible hydrophilic triethylene glycol termini. Silver and gold nanoparticles were firstly successfully prepared by using the Janus dendron as the reducing agent of Au(III) and Ag(I), and the stabilizer of the corresponding nanoparticles. The redox response of the Fc moiety was then employed to trigger the release of model drug, rhodamine B, encapsulated in supramolecular micelles formed by the self‐assembly of the Janus dendron. Finally, the precise and excellent metal‐complexing ability of the triazole group in this dendron was fully utilized to stabilize a water‐soluble Cu(I) catalyst, forming supramolecular nanoreactors for the catalysis of the copper(I)‐catalyzed azide alkyne cycloaddition click reaction in only water. The multifunctional characteristics of this dendron highlight the potential for organometallic Janus dendrimers and dendrons in the fields of functional materials and nanomedicines. 相似文献
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Cheng‐Xiong Liu Zhi‐yong Guo Yan‐Hong Xue Hong‐Yan Zhang Hong‐Qi Zhang Kun Zou Nian‐Yu Huang 《Magnetic resonance in chemistry : MRC》2012,50(4):320-324
Three new steroidal compounds with polyhydroxy groups, tupisteroide A–C (1–3), were obtained from the roots of Tupistra chinensis, together with one known compound (4) that was isolated from this plant for the first time. The structures of tupisteroide A–C were determined on the basis of one‐ and two‐dimensional NMR spectroscopy, including 1H–1H Correlation Spectroscopy, Heteronuclear Multiple Bond Correlation, and Heteronuclear Single Quantum Coherence experiments. The isolated compounds were evaluated for their cytotoxic activities against A549, HepG2, and CaSki cancer cell lines in vitro. Among them, compounds 1, 2, and 4 did not show significant inhibitory activity, but compound 3 showed cytotoxicity against A549 cancer cell lines with IC50 values of 25.0 μM. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献