Starting from（5S）-（L-menthyloxy）-3,4-dibromo-5H-furan-2-one and L-leucine,the title compound N-[（2S）-4-bromo-2-（L-menthyloxy）-5-oxo-2,5-dihydro-3-furyl]-L-leucine 5（C20H32BrNO5,Mr = 446.37） was obtained in o...Starting from（5S）-（L-menthyloxy）-3,4-dibromo-5H-furan-2-one and L-leucine,the title compound N-[（2S）-4-bromo-2-（L-menthyloxy）-5-oxo-2,5-dihydro-3-furyl]-L-leucine 5（C20H32BrNO5,Mr = 446.37） was obtained in one-pot process via the tandem Michael addition-elimination reaction in the presence of potassium hydroxide.The chemical structure and absolute configuration of the title compound were confirmed via rotation,UV-Vis,FT-IR,1H NMR,13C NMR,MS and elemental analysis,especially by the X-ray single-crystal diffraction.The crystal crystallizes in an orthorhombic system,space group P212121 with a = 12.5249（16）,b = 19.005（3）,c = 19.719（3） ,V = 4693.7（10） 3,Z = 8,Dc = 1.263 g/m3,μ = 1.778 mm-1,F（000） = 1872,the final R = 0.0617 and wR = 0.1576 for 3967 observed reflections（I 2σ（I））.X-ray analysis reveals that the title compound has two independent molecules in the asymmetric part of the unit cell with the two five-membered furanones being almost planar.The essential part of the electron delocalization is concentrated in the N（1）,C（3）,C（1）,C（37） and O（7） region and N（2）,C（28）,C（27）,C（30） and O（4） region in the other molecule respectively,but does not take place at the expense of delocalization within the ester function.展开更多
In this paper, stereocontrolled tandem Michael addition-elimination reaction of the novel chiral source, S-(ι-menthyloxy)-3,4-dichloro-2(5H)-furanone, with various thiols and amines has been investigated. A series of...In this paper, stereocontrolled tandem Michael addition-elimination reaction of the novel chiral source, S-(ι-menthyloxy)-3,4-dichloro-2(5H)-furanone, with various thiols and amines has been investigated. A series of new enantiomerically pure compounds, 5-(ι-menthyloxy)-4-substituted-3-cnloro-2(5H)-furanones, were obtained in good yields with d. e.(?)98% under mild conditions.展开更多
Based on the physiological structure of the intestine, a Caco-2/EAhy926 tandem compound model was constructed in order to simulate the intestinal-vascular barrier. This model was applied in the study of transcytosis o...Based on the physiological structure of the intestine, a Caco-2/EAhy926 tandem compound model was constructed in order to simulate the intestinal-vascular barrier. This model was applied in the study of transcytosis of nanoparticles, and it was compared with the traditional intestinal cell model in the whole study. Briefly, Fe3O4 nanoparticles with a size about 30 nm were used as model nanoparticles, which remained steady during transcytosis. The nanoparticles hardly had cytotoxicity to Caco-2 cells and EAhy926 cells within the incubation concentrations. The cell tandem model was established by connecting upper Caco-2 monolayer and lower EAhy926 monolayer. Based on the FD4 permeability or TEER, all cell models remained integrity within certain period of culture time. The expression of Claudin-4 or VE Cadherin demonstrated the presence of tight junctions. The intact morphology of microfilament F-actin indicated the favorable intracellular connection. It was found that the two-layer cell tandem model created a bigger barrier for the transcytosis of FD4 than Caco-2 and EAhy926 monolayer models, and the translocation of Fe3O4 nanoparticles showed a similar pattern. Interestingly, we found that the main barrier of tandem model for nanoparticles was caused by the upper Caco-2 cell monolayer, while the lower layer of EAhy926 monolayer remained high permeability. Generally, the cell tandem compound model established here enabled us to evaluate the impact of both intestinal epithelial and endothelial layer on transcytosis, and it might provide a novel approach to study bio-nano interaction in the intestine.展开更多
基金Supported by the National Natural Science Foundation of China (No. 20772035)the Natural Science Foundation of Guangdong Province (No. 5300082)
文摘Starting from（5S）-（L-menthyloxy）-3,4-dibromo-5H-furan-2-one and L-leucine,the title compound N-[（2S）-4-bromo-2-（L-menthyloxy）-5-oxo-2,5-dihydro-3-furyl]-L-leucine 5（C20H32BrNO5,Mr = 446.37） was obtained in one-pot process via the tandem Michael addition-elimination reaction in the presence of potassium hydroxide.The chemical structure and absolute configuration of the title compound were confirmed via rotation,UV-Vis,FT-IR,1H NMR,13C NMR,MS and elemental analysis,especially by the X-ray single-crystal diffraction.The crystal crystallizes in an orthorhombic system,space group P212121 with a = 12.5249（16）,b = 19.005（3）,c = 19.719（3） ,V = 4693.7（10） 3,Z = 8,Dc = 1.263 g/m3,μ = 1.778 mm-1,F（000） = 1872,the final R = 0.0617 and wR = 0.1576 for 3967 observed reflections（I 2σ（I））.X-ray analysis reveals that the title compound has two independent molecules in the asymmetric part of the unit cell with the two five-membered furanones being almost planar.The essential part of the electron delocalization is concentrated in the N（1）,C（3）,C（1）,C（37） and O（7） region and N（2）,C（28）,C（27）,C（30） and O（4） region in the other molecule respectively,but does not take place at the expense of delocalization within the ester function.
基金Project (No. 29132036) supported by the National Natural Science Foundation of China
文摘In this paper, stereocontrolled tandem Michael addition-elimination reaction of the novel chiral source, S-(ι-menthyloxy)-3,4-dichloro-2(5H)-furanone, with various thiols and amines has been investigated. A series of new enantiomerically pure compounds, 5-(ι-menthyloxy)-4-substituted-3-cnloro-2(5H)-furanones, were obtained in good yields with d. e.(?)98% under mild conditions.
基金The National Basic Research Program of China(973 program,Grant No.2015CB932100)the National Basic Research Program of China(Grant No.2015CB932100)+1 种基金National Natural Science Foundation of China(Grant No.81690264)the Innovation Team of the Ministry of Education(Grant No.BMU20110263)
文摘Based on the physiological structure of the intestine, a Caco-2/EAhy926 tandem compound model was constructed in order to simulate the intestinal-vascular barrier. This model was applied in the study of transcytosis of nanoparticles, and it was compared with the traditional intestinal cell model in the whole study. Briefly, Fe3O4 nanoparticles with a size about 30 nm were used as model nanoparticles, which remained steady during transcytosis. The nanoparticles hardly had cytotoxicity to Caco-2 cells and EAhy926 cells within the incubation concentrations. The cell tandem model was established by connecting upper Caco-2 monolayer and lower EAhy926 monolayer. Based on the FD4 permeability or TEER, all cell models remained integrity within certain period of culture time. The expression of Claudin-4 or VE Cadherin demonstrated the presence of tight junctions. The intact morphology of microfilament F-actin indicated the favorable intracellular connection. It was found that the two-layer cell tandem model created a bigger barrier for the transcytosis of FD4 than Caco-2 and EAhy926 monolayer models, and the translocation of Fe3O4 nanoparticles showed a similar pattern. Interestingly, we found that the main barrier of tandem model for nanoparticles was caused by the upper Caco-2 cell monolayer, while the lower layer of EAhy926 monolayer remained high permeability. Generally, the cell tandem compound model established here enabled us to evaluate the impact of both intestinal epithelial and endothelial layer on transcytosis, and it might provide a novel approach to study bio-nano interaction in the intestine.
