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1.
刘海兴 《理化检验(化学分册)》2008,44(4):332-333
采用毛细管电泳法测定了枳壳中辛弗林和柚皮素的含量.在30 mmol·L-1硼砂缓冲溶液(pH 10.0)的条件下,实现了被测组分的有效分离.测得枳壳中辛弗林含量为0.724 2 mg·g-1,相对标准偏差为5.9%(,n=5);柚皮素的含量为0.904 7 mg·g-1,相对标准偏差为3.8%(n=5).辛弗林和柚皮素的平均回收率分别为89.1%和99.6%. 相似文献
2.
β-分泌酶(BACE1)是治疗阿尔兹海默症(AD)的潜在靶点,BACE1抑制剂的开发已成为治疗AD的重要方向。本文运用比较分子相似性指数(CoMSIA)和分子对接法对66个氨基恶唑啉呫吨类BACE1抑制剂进行模拟分析,建立了可靠的构效关系预测模型(Q2=0.86, Rncv2=0.97, Rpre2=0.88),揭示了影响分子抑制活性的重要特征结构信息,发现抑制剂通过与BACE1之间形成的氢键作用和π-π堆积作用占据了分泌酶的S3、S1和S2"三个活性位点。实验所得模型和信息为后续新型高效BACE1抑制剂的结构优化和改造提供了重要的理论指导。 相似文献
3.
酸性铬兰K褪色分光光度法测定罐头中的铅 总被引:3,自引:0,他引:3
在H2SO4介质中,以2,2'联吡啶为活化剂,铅能灵敏地催化KIO4氧化酸性铬兰K的褪色反应,据此建立了测定痕量铅的催化动力学分光光度法.最大吸收波长位于526 nm,线性范围为0.002~0.006 μg/mL,检出限为2.0×10-4μg/mL.且大多数常见离子不干扰测定,可用于罐头中痕量Pb(Ⅱ)的测定. 相似文献
4.
The coordination polymer [Ca(L)2·(CH3OH)2]n (HL=N-phenylanthranilic acid) (1) was synthesized by the reaction of calcium perchlorate with N-phenylanthranilic acid in the CH3OH/H2O. It was characterized by elemental analysis, IR, thermal analysis and X-ray single crystal structure analysis. The crystal of the title complex [Ca(L)2·(CH3OH)2]n belongs to triclinic, space group P1 with a=0.751 5(3) nm, b=1.079 6(4) nm, c=1.629 5(6) nm, α=83.547(5)°, β=89.001(6)°, γ=72.257(5)°, V=1.251 0(8) nm3, Z=2, Dc=1.403 Mg·m-3, F(000)=556, and final R1=0.066 8, wR2=0.140 4. The complex comprises a seven-coordinated calcium(Ⅱ) center, with a O7 distorted pengonal bipyramidal coordination environment. Adjacent Ca(Ⅱ) ions are bridged by N-phenylanthranilicate groups, resulting in a 1D chain structure. The adjacent Ca…Ca distances are 0.382 8 nm and 0.384 6 nm. Furthermore, the molecules are connected by hydrogen bonds to form two dimensional layered structure. CCDC: 652445. 相似文献
5.
2D氢键网状Mg(Ⅱ)配合物的合成和晶体结构 总被引:1,自引:0,他引:1
The title complex [Mg(H2O)6]·(L)·(H2O) [L=2-formyl-benzenesulfonate-hydrazine] was synthesized by the reaction of magnesium chloride hexahydrate with 2-formyl-benzenesulfonic acid sodium-hydrazine in the CH3CH2OH/H2O. It was characterized by elemental analysis, IR and X-ray single crystal structure analysis. The crystal of the title complex [Mg(H2O)6]·(C14H12N2O7S2)·(H2O) belongs to triclinic, space group P1 with a=0.781 09(12) nm, b=0.781 27(13) nm, c=0.995 68(19) nm, α=102.054(2)°, β=92.331 0(10)°, γ=105.500(2)°, V=0.569 59(17) nm3, Z=1, Dc=1.559 Mg·m-3, μ=0.334 mm-1, F(000)=280, and final R1=0.033 9, wR2=0.091 6. The complex comprises a six-coordinated magnesium(Ⅱ) center, with a O6 distorted octahedron coordination environment. The molecules are connected by hydrogen bonds to form two dimensional network structures. CCDC: 716601. 相似文献
6.
The title complex Ca(L)2(H2O)5 [HL=salicylaldehyde-4-aminobenzene sulfonic acid] was synthesized by the reaction of calcium perchlorate with salicylaldehyde-4-aminobenzene sulfonic acid in the CH3CH2OH/H2O. It was characterized by elemental analysis, IR and X-ray diffraction single crystal structure analysis. The crystal of the title complex [Ca(H2O)5(C13H10NO4S)2] belongs to orthorhombic, space group Pca21 with a=1.162 47(18) nm, b=0.725 91(10) nm, c=3.516 3(3) nm, V=2.967 3(7) nm3, Z=4, Dc=1.528 Mg·m-3, μ=4.22 mm-1, F(000)=1 424, and final R1=0.044 2, wR2=0.098 3. The complex comprises a seven-coordinated calcium(Ⅱ) center, with a O7 distorted pengonal bipyramidal coordination environment. The molecules are connected by hydrogen bonds to form two dimensional layered structure. CCDC: 658852. 相似文献
7.
The reaction of 3-ethoxysalicylaldehyde-N,N-bis(3-aminopropyl)methylamine with Zn(Ⅱ) acetate in CH3CH2OH followed by recrystallization in CH3CH2OH gave rise to colourless block crystals of 3-ethoxysali-cylaldehyde-N,N-bis(3-aminopropyl)methylamine Zn(Ⅱ). The compound has been characterized by elemental analysis, IR spectrum, molar conductivity and X-ray diffraction structure determination single crystal. It crystallizes in monoclinic, space group P21/c with a=1.028 91(13) nm, b=1.400 35(12) nm, c=1.733 69(19) nm, V=2.476 6(5) nm3, Z=4, Mr=504.91, Dc=1.354 g·cm-3, T=298(2) K, F(000)=1 064, μ(Mo Kα)=0.102 7 cm-1, R=0.068 4 and wR=0.185 3 for 2 940 observed reflections with I>2σ(I). The fluorescence properties of ligand and the complex also have been investigated. The results show that the fluorescence intensity of the Zn(Ⅱ) complex is very stronger than the ligand. In the crystal, the molecules form 1D chain structure by π-π stacking. CCDC: 675010. 相似文献
8.
桑色素褪色光度法测定茶叶中的锰 总被引:2,自引:1,他引:1
锰是人体必需的微量元素,具有重要的生理功能和营养作用.茶树对锰有富集现象,茶叶是人们常用的饮料[1].因此,建立一种灵敏而又简便的测定痕量锰的分析方法,具有重要的实用价值. 相似文献
9.
β-分泌酶(BACE1)是治疗阿尔兹海默症(AD)的潜在靶点,BACE1抑制剂的开发已成为治疗AD的重要方向。本文运用比较分子相似性指数(CoMSIA)和分子对接法对66个氨基噁唑啉呫吨类BACE1抑制剂进行模拟分析,建立了可靠的构效关系预测模型(Q~2=0.86,R_(ncv)~2=0.97,R_(pre)~2=0.88),揭示了影响分子抑制活性的重要特征结构信息,发现抑制剂通过与BACE1之间形成的氢键作用和π-π堆积作用占据了分泌酶的S3、S1和S2'三个活性位点。实验所得模型和信息为后续新型高效BACE1抑制剂的结构优化和改造提供了重要的理论指导。 相似文献
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