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1.
设计并合成了一系列(E)-3-(4-羟苯基)-1-(哌啶-1-基)丙-2-烯-1-酮衍生物. 通过一维和二维核磁共振实验完成了1H和13C信号的指认. 通过ROESY、变温实验和分子模拟技术对这类化合物的构象进行了分析.  相似文献   

2.
采用量子化学计算方法研究了2-(N,N-二乙基苯胺-4-基)-4,6-双(3,5-二甲基吡唑-1-基)-1,3,5三嗪(dpbt)聚合物的电子结构和光物理性质,并且用二维实空间和三维实空间分析方法进行理论研究.结果表明, dpbt聚合物的第一激发态为分子内电荷转移激发态,存在较大的电偶极距变化和极化率,其中电偶极距变化与实验数值符合较好,理论计算所得到极化率数值与实验结果一致.S1激发态存在较大的电偶极距变化和极化率会导致非线性光学效应,促使高效的双光子吸收截面的形成.同时对外电场变化时dpbt的激发态性质进行理论研究.  相似文献   

3.
ABSTRACT

Optimized geometrical structure and harmonic vibration frequencies of prior synthesized (E)-3-phenyl-N-[4-(phenyl-amino) quinazoline-7-yl] acrylamide were computed by ab initio HF and DFT/B3LYP methods using both 6-31G* and 6-311G** basis sets and the Moller–Plesset second-order perturbation (MP2) method merely at the 6-31G* level. The infrared (IR) spectrum of the title compound has been measured in the range of 400–4000 cm?1. Complete vibrational assignments of the IR spectra were proposed. Moreover, the calculated wavenumbers of the title compound were compared with the experimental data. The correlation analyses indicate that good linearity relationships exist between the scaled theoretical vibration frequencies and the experimental values. Additionally, the atoms in molecules (AIM) method was applied to explore the possible intramolecular interactions in the title compound.  相似文献   

4.
以对硝基甲苯、3, 4-二甲氧基苯甲醛为起始原料,经过缩合,还原,重氮化水解,亲核取代反应,最终合成了新的化合物4-[(E)-2-(3, 4-二甲氧基苯基)乙烯基]苯氧基乙酸乙酯,用1H 和13C NMR及多种二维核磁共振谱确定了该化合物的结构,完成了1H 和13C NMR的归属,给出了分子中各氢,碳原子的准确化学位移.  相似文献   

5.
林祥潮  黄晓东 《光谱实验室》2009,26(6):1564-1567
报道了1-(4-硝基苯)-3-(2-吡嗪)-三氮烯(NPPT)的合成及与锌(Ⅱ)的显色反应。在非离子表面活性剂TritonX-100存在下,于pH8.8的KCl,H3BO3-NaOH缓冲介质中,NPPT与锌(Ⅱ)形成4∶1的黄棕色络合物,在465nm处有一最大吸收,表观摩尔吸光系数为3.15×104L·mol-1.cm-1,10mL溶液中,锌(Ⅱ)量在0—0.56μg范围内符合比尔定律。方法用于葡萄糖酸锌口服溶液中微量锌的测定,测定结果与AAS法相符。  相似文献   

6.
研究了2-(4-二甲氨基苯基)-5-氟-6-吗啉-1-氢-苯并咪唑(1)在不同pH条件下的紫外-可见吸收光谱,采用非线性最小二乘法得出分子1的三级加质子常数lgβ1, lgβ2, lgβ3分别为4.96±0.03, 5.72±0.07和7.95±0.10。当pH 3.40时,分子1主要以一价离子状态存在,紫外-可见吸收光谱及荧光光谱表明该条件下分子与小牛胸腺DNA存在明显的相互作用,并得出分子1与DNA的结合常数Kb为(2.30±0.10)×104 mol-1·L。当分子浓度为10-8~1.2×10-6 mol·L-1时,荧光强度随DNA含量的增加而线性增强,分子1是一种潜在的测定DNA的定量试剂。  相似文献   

7.
合成了一种新的取代苯并咪唑化合物 ,2 对二甲氨基苯基 5 氟 6 吗啉苯并咪唑 ,采用紫外 可见光谱、荧光光谱及荧光寿命等方法探讨了溶液pH值对该化合物吸收光谱的影响及其与 β 环糊精的作用。结果表明 ,pH >7 0时 ,该化合物在溶液中主要以中性分子状态存在 ,当 3 8相似文献   

8.
4-氟苯甲醛酪氨酸席夫碱(4-FT)由4-氟苯甲醛和L-酪氨酸钾盐在室温条件下反应制得,4-FT的结构通过1HNMR,FTIR和Raman测试得到确认。分别用密度泛函(DFT,density functional theory)理论的B3LYP(Becke’s three-parameter exchange functional(B3)with Lee,Yang,Parr(LYP))方法和从头算(ab initio)理论的HF(Hartree-Fock)方法,选用标准的6-31G**和6-31G*基组对化合物4-FT的几何构型进行优化。同时分别在B3LYP/6-31G**,B3LYP/6-31G*,HF/6-31G**和HF/6-31G*水平下计算4-FT的振动波数。用密度泛函(DFT)的B3LYP方法计算并校正后的波长数据比用从头算(ab i-nitio)的HF方法计算的结果更与实验数据吻合。  相似文献   

9.
The time-dependent density functional theory (TDDFT) method was carried out to investigate the excited state intramolecular proton transfer (ESIPT) process of 3-hydroxy-2-(pyridin-2-yl)-4H-chromen-4-one (1a). 1a has two tautomeric forms: one is 1a(O), which is induced by intramolecular hydrogen bond O-H?O=C, and the other one is 1a(N), which is caused by intramolecular hydrogen bond O-H?N. From excited state to tautomer excited state coming from ESIPT, the hydroxyl hydrogen breaks away and the dissociated hydrogen adsorbed on pyridinic nitrogen or carbonyl oxygen formed new intramolecular HB and the corresponding bond length and bond angle varied greatly. In comparison, a similar process of proton transfer for 1a(N)H+ protonated 1a(N) from ground state to excited state was obtained. This detailed proton transfer mechanism was provided by molecular orbitals analysis and it may be applied to molecular switch and organic Lewis acid/base. We investigated the excited state proton transfer mechanism of the four molecules through the theoretical method for the first time and gave unambiguous geometry of excited state.  相似文献   

10.
报道了新试剂1-(4-安替比林)-3-(8-喹啉)-三氮烯(APQT)的合成及其与镉(Ⅱ)的显色反应研究.在Triton X-100存在下,pH 10.5的Na2B4O7-NaOH的缓冲溶液中,试剂与镉(Ⅱ)形成2:1型的橙红色络合物,最大吸收波长为525nm,表观摩尔吸光系数为2.25×105L·mol-1·cm-1,镉含量在0-15μg/25mL范围内遵守比耳定律.  相似文献   

11.
The dissociation constant of l-acetyl-2-(coumariniminecarboxamide-3-yl) hydrazine (ACCH) has been determined potentiometrically in 0.1 M KC1 and 40% (v/v) ethanol-water mixture. The stepwise stability constants of the formed complexes of Mn2+, Co2+, Ni2+, Cu2+, Zn2+ and UO2 2+ with ACCH have been determined. The stability constants were found to UO2 2+ > Cu2+> Zn2+ > Ni2+ < CO2+ < Mn2+. The effect of temperature on the dissociation of ACCH and the stability of its formed complexes were studied. The corresponding thermodynamic functions were also determined and discussed. The spectral data of ACCH were investigated in pure organic solvents as well as in Britton Robinson buffer solutions of varying pH values. The dissociation constant pKH 1 of ACCH and the overall stability constants logβ of their complexes were determined in 20% (v/v) ethanol-water mixture at 298K.  相似文献   

12.
本文采用氢氟酸吡啶鎓在5′-位选择性断裂1,1,3,3-四异丙基二硅氧烷基保护基的方法得到了核苷衍生物N-异丁酰基-3′-O-(1-氟-1,1,3,3-四异丙基-1,3-二硅氧烷-3-基)-2′-苄氧羰基鸟苷(化合物1),并应用液相色谱串联质谱(LC-MS)、气相色谱-高分辨质谱(GC-HRMS)、液体1D和2D NMR谱(包括1H NMR、13C NMR、19F NMR、DEPT、1H-1H COSY、1H-13C HSQC和1H-13C HMBC),对产物的1H、13C和19F NMR信号进行了归属,确定了其结构.  相似文献   

13.
在TritonX-100表面活性剂存在下,pH为10.0-11.0的Na2B4O7-NaOH缓冲溶液中,1-(6-硝基-2-苯并噻唑)-3-(4-硝基苯)-三氮烯(NBTNPT)与铜生成2:1配合物。配合物的最大负吸收峰是540nm,表观摩尔吸光系数为1.15×105L·mol-1·cm-1。Cu2 的质量浓度在0-360μg/L符合比耳定律。测定铝合金样品中的微量铜,结果满意。  相似文献   

14.
在pH=10.97的NaB4O7-NaOH缓冲溶液中,表面活性剂Tween-80存在下,1-(6-羟基-2-嘌呤基)-3-[4-(苯基偶氮)苯基]-三氮烯(HPAPT)与镍的显色反应,形成一种稳定的1∶2红色配合物,其最大吸收波长位于540nm,表观摩尔吸光系数ε540=2.06×105L·mol-1·cm-1,Ni(Ⅱ)在0-15μg/25mL范围内符合比耳定律.结合萃取分离,应用于人发、大米和油菜中镍的测定,结果令人满意.  相似文献   

15.
合成了一种新三氮烯类显色剂1-(4-磺基苯)-3-(2-吡啶)-三氮烯(简称SPPT),并研究了在Triton X-100存在下,于pH为9.18的Na2B4O7-NaOH缓冲溶液中与镉的显色反应.结果表明,试剂与镉生成橙红色配合物.方法用于废水中微量镉的测定,结果令人满意.  相似文献   

16.
The enantiomeric composition and absolute configuration of 4-Amino-3-(benzo[b]furan-2-yl)-Butanoic Acids and of 4-Amino-3-(thien-2-yl)-Butanoic Acids 1 may be accurately determined by 1H and 13C nuclear magnetic resonance analysis of the corresponding derivatives 3 prepared by reaction with chiral reagents. Correlation with HPLC is signaled.  相似文献   

17.
18.
1-(4-Aminoantipyrine)-3-tosylurea (H2L) and its three lanthanide (III) complexes, M(H2L)3 3NO3 [where M = Nd(III), Sm(III) and Eu(III)], have been synthesized and characterized. In addition, the DNA-binding properties of the three complexes have been investigated by UV–vis (ultraviolet and visible) absorption spectroscopy, fluorescence spectroscopy, circular dichroism (CD) spectroscopy, cyclic voltammetry, and viscosity measurements. Results suggest that the three complexes bind to DNA via a groove binding mode. Furthermore, the antioxidant activity (superoxide and hydroxyl radical) of the metal complexes was determined by using spectrophotometer methods in vitro. These complexes were found to possess potent antioxidant activity and be better than standard antioxidants like vitamin C and mannitol. Absorption spectra of the complex 3 inTris-HCl buffer upon addition of calf-thymus DNA. [complex]=1×10-5 M, [DNA]=(0-1) ×10-5 M. Arrow shows the absorbance changing upon increasing DNA concentrations. Inset: plots of [DNA]/(εa – εf) versus [DNA] for the titration of DNA with the complex.  相似文献   

19.
作者合成了6-氟-3-(取代)苯基-4-(1H)-喹啉酮的5-氯衍生物与7-氯衍生物,二者极性差异小,难于分离,以混合物形式存在.所合成的化合物均未见文献报道,本文通过1H NMR上的化学位移、积分面积以及偶合常数确证了混合物中两组份的结构.  相似文献   

20.
研究了 4 - (2 -羟基 - 4-硝基苯偶氮 ) - 1-苯基 - 3-甲基吡唑啉酮 (HNAPMP)与镁的显色反应 ,在 p H=10的硼砂 -氢氧化钠缓冲介质中 ,HNAPMP与镁反应生成 2∶ 1稳定络合物 ,λmax=5 2 2 nm,ε=3.5 8× 10 4L·mol-1· cm-1。镁含量在 0— 2 0 μg/2 5 m L范围内符合比耳定律 ,方法用于烟草样品中镁含量的测定 ,结果令人满意  相似文献   

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