Reversible Photo‐Mechanical Switching Behavior of Azobenzene‐Containing Semi‐Interpenetrating Network under UV and Visible Light Irradiation

Summary: Light‐induced reversible changes in elasticity of semi‐interpenetrating network (semi‐IPN) films bearing azobenzene moieties were achieved under both ultraviolet (UV) and visible light irradiation. The semi‐IPN film was prepared by a cationic copolymerization of azobenzene‐containing vinyl ethers in a linear polycarbonate (PC) film as a matrix. When the irradiation was switched on and off, the semi‐IPN film showed rapid reversible deformation with the same behavior occurring over a range of wavelengths, including both the UV and visible regions. The observed reversible deformation of the film was attributed to the decrease in the film's elasticity, which was assumed to be caused by the frequent trans‐cis cycling isomerization of azobenzene moieties taking place during the UV and visible light irradiation. This cycling makes it difficult for the azobenzene groups to aggregate, thus hindering their ability to function as pseudo‐crosslinking points.

     

人参皂苷R_d及其C_(12)手性异构体对缺氧/再复氧后蛋白酪氨酸磷酸化的抑制作用

目的　探讨人参皂苷Rd C12 手性碳构型改变与其药理活性的关系。方法　建立牛主动脉内皮细胞 (BAEC)缺氧 /再复氧 (H/R)损伤模型 ;MTT法研究Rd 及Rd C12 手性异构体 (12 epi Rd)对H/R损伤BAEC的保护作用 ;Western印迹法检测蛋白酪氨酸磷酸化 (TPP)水平 ,研究二者对H/R损伤BAEC的TPP水平的影响。结果　 0 .5～ 6 4μmol·L- 1的Rd 及12 epi Rd 能浓度依赖性的保护H/R损伤的BAEC ,二者所能达到的最大存活率分别为 (72 .7± 1.5 ) %和 (70 .0± 1.5 ) % ,EC50 分别为 (1.0 6± 0 .19)和 (1.88±0 .5 5 ) μmol·L- 1(P <0 .0 5 )。Rd 及 12 epi Rd 均可抑制H/R引起的TPP水平的提高 ,浓度为 1,4 ,16μmol·L- 1时 ,Rd 的抑制率分别可达 (2 4 .3± 6 .8) % ,(5 2 .6± 8.7) %及 (73.4± 11.4 ) % ;而 12 epi Rd 的抑制率分别可达 (12 .8± 4 .4 ) % ,(2 4 .1± 10 .3) %及(4 2 .5± 13.0 ) % ,二者在三个浓度点的抑制率均有显著性差异 (P <0 .0 5 )。结论　人参皂苷Rd C12 手性碳构型的改变对其保护H/R损伤BAEC的作用及抑制H/R诱导的TPP水平增强的作用有一定的影响。RdC12 手性碳构型改变明显降低其抑制TPP增强的作用可能是其保护作用下降的重要原因之一。     

那格列奈及其片剂中L-异构体的HPLC测定

建立了HPLC法测定那格列奈及其片剂中的杂质L-异构体的含量.采用以α-酸性糖蛋白键合硅胶为固定相的手性色谱柱,0.02mol/L磷酸钾缓冲液(pH 7.1)-乙腈(98:2)为流动相,检测波长210nm,L-异构体检测限为2ng,平均回收率为98.0%.     

Effect of low-molecular-weight heparin on the commitment of bone marrow cells to liver sinusoidal endothelial cells in CCl(4)-induced liver injury.

BACKGROUND/AIMS: Recently liver regeneration by bone marrow transplantation has been proposed as an alternative source of functional liver cells. We investigate commitment of bone marrow cells (BMCs) to liver regeneration and the effect of dalteparin sodium (DS) on regeneration of the damaged liver caused by carbon tetrachloride (CCl(4)) administration in the mice. METHODS: Liver injury was produced in 8-week-old mice by treating with CCl(4) for 4 weeks. Thereafter, mice received a lethal dose of irradiation (10Gy) to whole body, followed by injection of 1x10(7) green fluorescent protein (GFP)-positive BMCs via the tail vein. DS (50IU/kg, intraperitoneally) was administered daily for 28 consecutive days starting at 1 day post-BMC transplantation. Lineage marker analysis of GFP-positive liver cells was performed immunostaining with a CD31 antibody. RESULT: Four weeks after BMC transplantation, GFP-positive cells in the CCl(4)-damaged liver could be detected in the lobule displaying a meshwork architecture extending from the periportal to pericentral regions, a pattern simulating sinusoidal lining. This localization of GFP-positive cells suggested that these cells were closely associated with sinusoidal endothelial cells. By staining the GFP-positive cells for CD31, it was confirmed that the majority of the GFP-positive cells are also positive for CD31. The GFP(+)CD31(+) cells were barely detected in the control group (1.0+/-1.2 per field). In marked contrast, a numerous number of GFP(+)CD31(+) cells were detected in the liver section obtained from the CCl(4)-induced liver damage group (3.8+/-1.3 per field, P<0.05 versus control). The number of GFP(+)CD31(+) cells in CCl(4) plus DS-treated group was further increased to 8.3+/-1.3 per field (P<0.05 versus CCl(4)-induced liver damage group). CONCLUSION: The majority of GFP-positive BMCs was committed to sinusoidal endothelial cells. DS promoted BMC differentiation into sinusoidal endothelial cells in the CCl(4)-damaged liver.     

3,4-二氢喹啉-2(1H)-酮衍生物(±)-SIPI6360及其光学异构体的合成和药理学评价(英文)

7-[3-[4-(6-氟苯并[d]异(口恶)唑-3-基)哌啶-1-基]丙氧基]-3-甲基-3,4-二氢喹啉-2(1H)-酮[(±)-SIPI6360]为本课题组发现的多靶点抗精神分裂症候选新药,其化学结构中存在一个手性中心。本试验报道了(±)-SIPI6360及其2个光学异构体的制备和体内外药理性能的比较研究。结果显示,(±)-SIPI6360及其光学异构体的体内外药效、大鼠体内药动学特性及毒性方面无显著性差别。基于原料制备成本,确定(±)-SIPI6360消旋体作为抗精神分裂症候选新药的更优结构。     

海南粗榧总碱中化学成分研究

目的研究海南粗榧Cephalotaxus hainanensis的生物碱类成分。方法采用硅胶、Sephadex LH-20和ODS等多种柱色谱技术进行分离纯化,根据化合物理化性质及波谱数据鉴定化合物结构。结果从海南粗榧总碱中分离得到13个化合物,分别鉴定为三尖杉碱(1)、异三尖杉酮碱(2)、三尖杉酮碱(3)、三尖杉胺G(4)、(2R,3S,4S,5S)-2,3-二羟基三尖杉碱(5)、乙酰三尖杉碱(6)、脱氧三尖杉酯碱(7)、(R)-丽江三尖杉碱(8)、(S)-丽江三尖杉碱(9)、3-表里哈灭里辛碱异构体(10)、1,4-N-二异丙胺蒽醌(11)、苯甲酸(2-乙基)-正己酯(12)和β-谷甾醇(13)。结论化合物3~6和10~13为首次从海南粗榧中分离得到。     

Synthesis of [3α‐3H] 17α‐Hydroxy pregnenolone and [3α‐3H] Pregnenolone

For the first time, [3α‐³H] 17α‐hydroxy pregnenolone (1) was synthesized through a multiple step sequence. The presence of [3β‐³H] isomer in RP‐HPLC purified product was identified by tritium NMR. The [3β‐³H] isomer was then separated from [3α‐³H] 17α‐hydroxy pregnenolone with chiralPAK AD‐H column. [3α‐³H] pregnenolone (2) was synthesized from commercial available 5‐pregnen‐3,20‐dione in one step with an improved procedure.     

共轭亚油酸构效关系及其分子药理研究进展

共轭亚油酸是一系列异构体的总称，其中具有多种生物功能的异构体主要是c9，t11-共轭亚油酸和t10，c12-共轭亚油酸。本文简要阐述了共轭亚油酸活性异构体的分布和来源，并重点综述了c9，t11-共轭亚油酸和t10，c12-共轭亚油酸这两种异构体对动物体内脂肪、脂类代谢和癌症的影响差异，从构效关系上分析了它们的药理作用机制。