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1.
Schiff碱含有-RC=N-基团,自1864年发现以来[1,2],由于Schiff碱及其配合物具有杀菌抗病毒抗癌[3]、可逆结合氧气[4]、非线性光学[5]、光致和热致变色[6]、荧光[7]、仿酶催化[8]等一系列优良性能,人们进行了广泛而深入的研究。Schiff碱的合成一般采用溶液合成方法,反应需要有机溶  相似文献   

2.
化合物3-甲基-2-戊烯-4-炔-1-醛两端均为活性官能团,在分子连接及成环反应中能够起到非常重要的作用,是合成轮烯酮[1-7],脱落酸[8]和二苯基二苯并环辛烯[9]等的重要中间体.  相似文献   

3.
文献[1]报道N-甲基-N-(2-甲基丙烯酰氧乙基)苯胺(MEMA)单体,由于同一分子中含有缺电子碳碳双键和给电子发色基团(芳叔胺氮上孤对电子),因此当链节克分子浓度相等时,单体的荧光强度要比其均聚物的荧光强度低得多,归之为单体“结构自猝灭”所致。这是由于共存在单体分子中的吸电子双键基团和给电子的荧光基团在光照下于分子内或分子间产生激基复合物所致。这种现象称为“结构自猝灭现象”。聚合物无双键存在,因而其荧光强度比单体高得多。  相似文献   

4.
报道了一个基于光致电子转移(PET)机理的双稳态荧光分子开关,其中具有氧化还原活性的二茂铁基团作为荧光团蒽PET过程的氧化还原控制单元,通过双Schiff碱C=N键与蒽相连。研究了不同条件下蒽的荧光发射行为。以不同的化学试剂作为体系的输入信号,以不同的荧光发射强度作为输出信号,利用荧光分子开关的质子化反应和氧化反应实现了一个分子水平的逻辑功能。输入信号及其相应的输出结果在分子水平上符合数字逻辑与门的真值表。  相似文献   

5.
以对氯苯乙酮为原料合成了两种9,10-二硫代蒽衍生物A、B,其结构经IR和1H NMR表征。通过紫外吸收光谱法考察了这两种化合物对金属阳离子的识别性能,结果表明,化合物A对Cu2+具有高选择性识别能力。初步讨论了主客体识别作用的机制,说明在主客体识别中分子尺寸的匹配和化合物中基团的空间合理排布是化合物A和Cu2+间能发生相互作用的重要根据。  相似文献   

6.
以粘卤酸为起始原料,经还原缩合、再缩合、成醚反应合成了15个5-苯亚甲基-3,4-二卤-2(5H)-呋喃酮衍生物4a-4o,其结构经~1H-NMR、~(13)C-NMR、MS谱确证.研究所有化合物对细菌脂多糖LPS诱导RAW264.7细胞的抗炎作用.初步活性结果显示,4a-4o对于LPS诱导RAW264.7细胞所产生的NO有抑制作用,其中化合物4h和4i的NO抑制率比较高.生物活性的研究结果表明,卤代呋喃酮结构、吡啶环上连有给电子基团都可以提高化合物的体外抗炎生物活性,为临床上炎症等相关疾病的治疗提供新的药物设计和研究思路.  相似文献   

7.
用NMR分子力学计算和单晶X射线衍射方法对 2 (1,11 十一亚甲基 ) 5 取代亚胺基 Δ3 1,3,4 噻二唑啉 (1)的构象进行了分析 ,结果表明 ,标题化合物 1的十二员环采取D4 对称的 [3333]构象 ,噻二唑啉环与十二员环近似平面几乎垂直构成螺环 ,位于 [3333]构象的一个角碳 ,亚胺基上的取代基对母体十二员环骨架的构象及13 CNMR化学位移影响很小  相似文献   

8.
噻唑环及其衍生物广泛存在于具有生物活性的分子中[1]可用于抗生素和消炎药的制备[2]。本文合成的几种噻唑基衍生物—类以HIV蛋白酶为靶点的新型抗艾滋病药物利托那韦的重要中间体[3-5],对其合成工艺的研究具有较实际的意义。噻唑环衍生物可通过α-卤代羰基化合物与硫代酰胺缩合而成[6],α-巯基酮与腈缩合反应得到,也可采用醛与半胱氨酸缩合,再与二氧化锰作用得噻唑类化合物[7]。本文采用α-氯代羰基类化合物与硫代酰胺缩合而得三种噻唑类化合物,产率较为理想。1合成路线设计合成路线设计可表示如下图1图1目标化合物的合成路线F ig.1 The …  相似文献   

9.
在离子液体[bmim]Br中, 5,5-二甲基-1,3-环己二酮与N-芳亚甲基芳胺反应合成了一系列四氢吖啶-1,8-二酮衍生物, 该反应具有适应性广、产率高、污染少、环境友好等优点.  相似文献   

10.
本文报道了一种新型中位-吡啶取代的硼-二吡咯亚甲基(BDP)染料的合成与晶体结构表征,发现中位-吡啶环与因达省平面几乎正交,其二面角为88.2°。同时对它的吸收和稳态荧光性质研究表明:当溶液的酸性增强时,化合物的荧光减弱,pKa为2.24。该化合物在可见光激发下,可以作为比较灵敏的pH荧光探针。  相似文献   

11.
The occurrence of polycyclic aromatic hydrocarbons (PAHs) in nine edible oils of three categories of oil samples, such as soy bean oil, mustard oil and coconut oil, has been studied to determine the contamination degree of this type of oil samples. Eight major carcinogenic polycyclic aromatic hydrocarbons (PAHs), such as naphthalene, anthracene, phenanthrene, fluorene, pyrene, crysene, benzo(a)pyrene and benzo(a)anthracene, were identified and quantified in the extract of edible oils collected from Bangladeshi Markets by gas chromatography and mass spectroscopy. All of the carcinogenic PAHs are not present in the edible oils. A few of the carcinogenic PAHs are present in the oils but it is within the permissible limit. The results for the recoveries of naphthalene, fluorene, phenanthrene, anthracene, pyrene, crysene, benzo(a)anthracene and benzo(a)pyrene were in the range of 56–84%. The limit of detection (LOD) of the GC–MS method, established at signals three times that of the noise for naphthalene, fluorene, phenanthrene, anthracene, pyrene, crysene, benzo(a)anthracene and benzo(a)pyrene, was 2.0–2.5 ng, respectively.  相似文献   

12.
We designed a trifunctional initiator ( 3 ) containing anthracene, bromide, and OH functionalities and subsequently used as an initiator in atom transfer radical Polymerization (ATRP) of styrene to yield linear polystyrene (PS) with α‐anthracene, OH, and ω‐bromide terminal groups, of which bromide is later transformed into azide to result in the linear anthracene‐, OH‐, and azide‐terminated PS (l‐α‐anthracene‐OH‐ω‐azide‐PS). The copper‐catalyzed azide–alkyne cycloaddition reaction between l‐α‐anthracene‐OH‐ω‐azide‐PS and α‐furan‐protected‐maleimide‐ω‐alkyne linkage, 4 afforded the linear anthracene‐, OH‐, and maleimide‐terminated PS. The cyclization via intramolecular Diels–Alder click reaction of this linear PS and the subsequent conversion of the hydroxyl into bromide resulted in the cyclic PS with one bromide located on the ring, (c‐PS)‐Br. Finally, the c‐PS‐Br was clicked with either well‐defined tetramethylpiperidine‐1‐oxyl‐terminated poly(ethylene glycol) (PEG) or poly(ε‐caprolactone) (PCL) yielding the tadpole polymer, (c‐PS)‐b‐PEG or (c‐PS)‐b‐PCL. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

13.
蒽端基聚对苯亚乙炔的发光性能   总被引:1,自引:0,他引:1  
牛俊峰  杨慕杰  孙景志 《化学学报》2002,60(6):1139-1143
报道了一种新的蒽端基聚对苯亚乙炔的合成与发光特性,分别考察了聚合物 P2的紫外吸收,荧光发射和电致发光光谱。结果表明,在聚对苯亚乙炔主链末端引 入蒽基团可改变其有效共轭长长及发光颜色,合成的模型小分子可证明这一点。电 致发光器件ITO/P2/Al在600 nm处发红光。  相似文献   

14.
Atom transfer radical polymerization was used to prepare well‐defined vinyl polyoxadiazole homomacromonomers with a properly modified α‐dicarboxylic acid methyl ester as the initiator. Macromonomers of various molecular weights with narrow polydispersities in some cases were obtained, as proved by gel permeation chromatography (GPC). The structures of the obtained macromonomers were then identified with 1H NMR spectroscopy. These macromonomers were subsequently copolymerized with a dihydroxy anthracene based monomer by a polycondensation technique, and this resulted in polymacromonomers. Coil–rod–coil copolymers containing side‐chain anthracene and oxadiazole units were also synthesized by atom transfer radical polymerization. The resulting copolymers combined an anthracene derivative as the rigid block with a random copolymer of the desired anthracene‐ and/or oxadiazole‐based monomers as the flexible block. These copolymers were primarily characterized with GPC and 1H NMR techniques. Additionally, the optical properties of all these copolymers were investigated in detail, and they suggested energy transfer from the oxadiazole to the anthracene chromophores, which became much more efficient in the solid state. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1049–1061, 2005  相似文献   

15.
In this study, an equimolar mixture of oxanorbornenyl‐anthracene (ONB‐anthracene), oxanorbornenyl‐bromide (ONB‐Br), and oxanorbornenyl tosylate (ONB‐OTs) was polymerized via ring opening metathesis polymerization using the first generation Grubbs' catalyst in CH2Cl2 at room temperature to form poly(ONB‐anthracene‐co‐ONB‐Br‐co‐ONB‐OTs)10 copolymer as a main backbone. Next, this main backbone was sequentially clicked with a furan protected maleimide‐terminated poly(methyl methacrylate), 2,2,6,6‐tetramethyl‐1‐piperidinyloxy‐terminated poly(ethylene glycol), and alkyne‐terminated poly(ε‐caprolactone) (PCL20‐alkyne) via Diels–Alder, nitroxide radical coupling, and copper‐catalyzed azide‐alkyne cycloaddition, respectively, to yield a poly(ONB‐g‐PMMA‐co‐ONB‐g‐PEG‐co‐ONB‐g‐PCL)10 heterograft brush copolymer © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013  相似文献   

16.
A new family of covalently linked ‘Sn(IV) porphyrin-anthracene’ diad (1), triad (2) and tetrad (3) donor-acceptor (D-A) systems have been designed and synthesized in good-to-moderate yields. While diad 1 possesses one anthracene subunit at the peripheral (meso) position of the tin(IV) porphyrin scaffold, triad 2 possesses twotrans axial anthracene subunits at the tin(IV) centre. On the other hand, tetrad 3 is endowed with both the peripheral and axial anthracene subunits in its architecture. These D-A systems have been fully characterised by elemental analysis, FAB-MS, UV-Vis,1H and13C NMR and electrochemical methods. UV-Vis,NMR and redox data suggest the absence of intramolecular π-π interaction between the porphyrin and the anthracene/s in 1–3. Fluorescence from the anthracene subunit in 1 and 3 is found to be quenched in comparison with the fluorescence of free anthracene in four different solvents. This is not the case with compound 2. Excitation spectral data provides evidence for an intramolecular excitation energy transfer (EET) from the singlet anthracene to the porphyrin in 1 and 3. The energy transfer efficiency is in the order: 2 (almost negligible) < 3 (~30%) < 1 (nearly quantitative), with the peripheral anthracene → porphyrin pathway being largely favoured. This orientation dependence of EET could be analysed using Forster's dipole dipole mechanism.  相似文献   

17.
Two functional monomers, methacrylic acid 4‐(2‐benzoxazol)‐benzyl ester (MABE) containing the benzoxazole group and 4‐(2‐(9‐anthryl))‐vinyl‐styrene (AVS) containing the anthracene group were synthesized by rational design. The MABE was polymerized via atom transfer radical polymerization (ATRP) using ethyl 2‐bromoisobutyrate (EBIB) as initiator in CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine (PMDETA) catalyst system; block copolymers poly(MABE‐b‐AVS) was obtained, which was conducted by using poly(MABE) as macro‐initiator, AVS as the second monomer, and CuBr/PMDETA as catalyst. The constitute of two monomers in block copolymers poly(MABE‐b‐AVS) by ATRP could be adjusted, that is the constitute of the benzoxazole group and the anthracene group could be controlled in AB‐type block copolymers. Moreover, the fluorescent properties of homopolymers poly(MABE) and block copolymers poly(MABE‐b‐AVS) were discussed herein. With the excitation at λex = 330 nm, the fluorescent emission spectrum of poly(MABE) solution showed emission at 375 nm corresponding to the benzoxazole‐based part; with the same excitation, the fluorescent emission spectrum of poly(MABE‐b‐AVS) solution showed a broad peek at 330–600 nm when the monomer AVS to the total monomers mole ratio was 0.31, and the fluorescent emission spectrum of poly(MABE‐b‐AVS) in film state only showed one peak at 525 nm corresponding to the anthracene‐based unit that indicated a complete energy transfer from the benzoxazole group to the anthracene group. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3894–3901, 2007  相似文献   

18.
戴雪伟  卫碧文  望秀丽  于文佳  徐永威 《色谱》2015,33(10):1059-1064
建立了一种超高效合相色谱-二极管阵列检测器快速分析塑料制品中萘、苊烯、苊、芴、菲、蒽、荧蒽、芘、苯并(a)蒽、(屈艹) 、苯并(b)荧蒽、苯并(k)荧蒽、苯并(j)荧蒽、苯并(e)芘、苯并(a)芘、茚并(1,2,3-cd)芘、二苯并(a,h)蒽、苯并(g,h,i)苝(二萘嵌苯)的方法。以甲苯为溶剂,超声萃取实际塑料制品中的多环芳烃,经超高效合相色谱分析。采用Daicel IB-3手性色谱柱,以CO2为流动相,甲醇/乙腈(25:75, v/v)为流动相助溶剂,在柱温为40 ℃,背压为15.17 MPa的条件下,18种多环芳烃在8.5 min之内实现基线分离。18种多环芳烃的线性范围为0.05~50 mg/L(r≥0.9995),定量限(S/N> 10)为0.05 mg/L。加标回收率为78.3%~117.6%,相对标准偏差(RSD, n=5)小于5%。该方法具有分析速度快、分离效率高、节约有机溶剂的优点。  相似文献   

19.
通过偶联修饰的方法合成了水溶性磺化杯芳烃修饰的金纳米粒, 并研了其对多环芳烃的比色检测. 结果表明, 磺化杯芳烃修饰的金纳米粒对蒽具有良好的识别选择性. 该比色探针对蒽的检测限可达到2×10-6 mol/L. 这种比色传感器能够实现现场原位检测.  相似文献   

20.
张小涛  张丽  阮艺斌  王维维  姬厚伟  万强  林福呈  刘剑 《色谱》2017,35(10):1105-1110
建立了气相色谱-串联质谱同时检测卷烟滤嘴中15种多环芳烃的方法。卷烟滤嘴用二氯甲烷振荡萃取后,经0.22μm有机相滤膜过滤,采用DB-5MS色谱柱(30 m×0.25 mm,0.25μm)进行分离,电子轰击源、正离子模式下以多反应监测模式进行检测,内标法进行定量。15种多环芳烃(苊烯、苊、芴、菲、蒽、荧蒽、芘、苯并[a]蒽、屈、苯并[b]荧蒽、苯并[k]荧蒽、苯并[a]芘、二苯并[a,h]蒽、苯并[g,h,i]苝和茚并[1,2,3-c,d]芘)的线性关系良好,相关系数(R~2)为0.991 4~0.999 9。15种多环芳烃在低、中、高3个添加水平下的平均回收率为81.6%~111.2%;除了芴在低添加水平时相对标准偏差为19.2%外,其他相对标准偏差均小于16%。15种多环芳烃的检出限为0.02~0.24 ng/滤嘴,定量限为0.04~0.80 ng/滤嘴。方法前处理简便,具有快速、准确、灵敏度高及重复性好的优点,适用于卷烟滤嘴中多环芳烃的分析。  相似文献   

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