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1.
两种偶氮苯冠醚的合成及其光致变色机理   总被引:1,自引:0,他引:1  
报道了4-氮杂15-冠-5-4'-甲氧基偶氮苯和4-氮杂15-冠-5-4'-硝基偶氮苯的合成及其分子内扭曲电荷转移的光致变色机理.  相似文献   

2.
报道了4-氮杂15--5-4'-甲氮基偶氮苯和4-氮杂15-冠-5-4'-硝基偶氮苯的合成及其分子内扭曲电荷转移的光致变色机理。  相似文献   

3.
Photoisomerizable glyco‐SAMs (self‐assembled monolayers), utilizing synthetic azobenzene glycoside derivatives were fabricated. The ultimate goal of this project is to assay the influence of the 3D arrangement of sugar ligands on cell adhesion, and eventually make cell adhesion photoswitchable. However, it is a prerequisite for any biological study on the spatial conditions of carbohydrate recognition, that photoisomerization of the surface molecules can be verified. Here, we employed IRRAS and XPS to spectroscopically characterize glyco‐SAMs. In particular and unprecedented to date, we prove reversible EZE isomerization of azobenzene glycoside‐terminated SAMs.  相似文献   

4.
一类芳香族偶氮化合物的合成及表征   总被引:13,自引:0,他引:13  
采用重氮偶合反应合成了一系列不同对位取代的4-[N,N-(二羟乙基)]氨基偶氮苯化合物,其结构用元素分析,IR,1HNMR,DSC,DSC等进行表征和确认。  相似文献   

5.
Two spirostanol saponins(gracillin and dioscin)which have the typical sugar moieties were synthesized facilely by a general approach.  相似文献   

6.
李聪  于世钧  张跃  王璐  冯春梁  靳奇峰 《应用化学》2010,27(10):1138-1143
合成了同时含有偶氮苯和1,3,4-噁二唑结构的新型共轭聚合物(LPOXD),采用FT-IR、UV-Vis、1H NMR、GPC、TGA和DSC测试技术对其结构进行了表征。 结果表明,所得共轭聚合物的特性粘数为0.02960 L/g,Mw和分子量分布指数PDI分别为8500 g/mol和1.55。 质量损失5%的温度为290 ℃,Tg为92.8 ℃。 长烷氧基侧链的引入极大地提高了LPOXD在氯仿和四氢呋喃等有机溶剂中的溶解性。 采用紫外-可见吸收光谱、荧光光谱及循环伏安对LPOXD的光电性能进行了研究。 结果表明,在365 nm紫外光照射下,LPOXD中偶氮苯发生反-顺异构化;350 nm光激发下,LPOXD在蓝紫光波长范围内发射荧光;循环伏安测试得出LPOXD最高占有轨道(HOMO)能量和最低空轨道(LUMO)能量分别为-5.96和-3.17 eV。  相似文献   

7.
A new design is presented for the incorporation of spiropyran photoswitches into nucleic acids by oligonucleotide solid phase synthesis. This design enables interaction of the 6‐nitrospirobenzopyran (NitroBIPS) photoswitch with the adjacent nucleobases and leaves the photochemical properties of NitroBIPS intact. UV/Vis spectroscopy and HPLC revealed that NitroBIPS incorporated into DNA consists of up to 40 % merocyanine in its thermal equilibrium and undergoes reversible switching between the photoisomeric spiropyran (SP) and merocyanin (MC) state by alternating excitation using visible light or heat for at least fifteen switching cycles. Exchanging the chromene part of NitroBIPS on the DNA level gives access to differently substituted spiropyran derivatives allowing the screening for spiropyrans with suitable properties in a straightforward manner. Thus, by incorporating the highly hydrolysis‐stable pyrido‐spiropyran derivative PyBIPS pure light‐triggered reversible switching of a spiropyran in DNA has been realized for the first time. Therefore, this design represents a new useful platform for investigating the photochromic behavior of different spiropyran photoswitches in a nucleic acid environment and for using spiropyrans to induce light‐ or heat‐triggered changes in conformations or in fluorescence quenching properties of oligonucleotides.  相似文献   

8.
刘佳  田进涛 《合成化学》2016,24(4):338-341
以苯胺或对硝基苯胺为起始原料,通过重氮偶合法合成了4种分别含有硝基、氨基和不同数目偶氮基的偶氮苯化合物(1~4),其结构经1H NMR和FT-IR确证。研究了1~4在紫外灯(12 W)照射下随时间变化的UV-Vis谱图。结果表明:含有给电子基团(NH2)偶氮苯的光致异构化速率较含有吸电子基团(NO2)时更快,NO2对分子的异构化有一定抑制作用;分子中偶氮基的数目增加时,顺反异构化过程也受到影响。  相似文献   

9.
Azobenzene photoswitches are valuable tools for controlling properties of molecular systems with light. We have been investigating azobenzene glycoconjugates to probe carbohydrate-protein interactions and to design glycoazobenzene macrocycles with chiroptical and physicochemical properties modulated by light irradiation. To date, direct conjugation of glycosides to azobenzenes was performed by reactions providing target compounds in limited yields. We therefore sought a more effective and reliable coupling method. In this paper, we report on a straightforward thioarylation of azobenzene derivatives with glycosyl thiols as well as other thiols, thereby increasing the scope of azobenzene conjugation. Even challenging unsymmetrical conjugates can be achieved in good yields via sequential or one-pot procedures. Importantly, red-shifted azoswitches, which are addressed with visible light, were easily functionalized. Additionally, by oxidation of the sulfide bridge to the respective sulfones, both the photochromic and the thermal relaxation properties of the core azobenzene can be tuned. Utilizing this option, we realized orthogonal three-state photoswitching in mixtures containing two distinct azobenzene thioglycosides.  相似文献   

10.
齐程远  于世钧  王红  王赫麟  靳奇峰 《应用化学》2012,29(11):1240-1245
合成了同时含有偶氮苯和1,3,4-噻二唑的新型聚酰胺(P1,P2),采用FT-IR、1H NMR、GPC和TGA技术对其结构进行了表征和热性能测试。 P1和P2的特性粘数分别为0.14和0.12 dL/g,质均相对分子质量Mw和相对分子质量分布指数PDI分别为28.8、24.8 kg/mol和1.71、1.74,质量损失5%的温度分别为320和322 ℃。 长烷氧基侧链的引入改善了聚合物在氯仿和四氢呋喃等有机溶剂中的溶解性。 采用紫外-可见吸收光谱、荧光光谱对聚合物的光学性能进行了研究。 结果表明,在365 nm紫外光照射下,聚合物中偶氮苯发生反 顺异构化,P1和P2光稳态时顺式异构体比例分别为86.8%和77.4%,反 顺异构化效率分别为82.7%和73.7%。 在366和363 nm光激发下,P1和P2的固体分别在418和425 nm处紫光波长范围内发射荧光。  相似文献   

11.
含苯氧基萘并萘醌和偶氮苯双变色基化合物的合成和性质   总被引:2,自引:0,他引:2  
通过6-氯-5,12-萘并萘醌与4-羟基偶氮苯及其衍生物的反应合成了3种含苯氧基萘并萘醌和偶氮苯光致变色基的双变色基化合物,6-[4-(苯偶氮基)苯氧基]-5,12-萘并萘醌(5),6-[4-(p-乙氧基苯偶氮基)苯氧基]-5,12-萘并萘醌(6)和6-[4-(p-硝基苯偶氮基)苯氧基]-5,12-萘并萘醌(7).这些化合物的苯氧基萘并萘醌变色基的UV诱导光致变色性较弱;基于氨与苯氧基萘并萘醌ana显色体的不可逆反应,化合物5和6DMSO溶液在365nm紫外光辐照光稳态(PSS)下的ana醌式摩尔分数估计分别为22%和17%.这些结果说明,苯偶氮基对苯氧基萘并萘醌变色基的光致变色性质有着极强的影响.另一方面,与4-羟基偶氮苯母体不同,这些双变色基化合物在DMSO中偶氮苯变色基的顺式异构体是相对稳定的  相似文献   

12.
合成了新型偶氮苯金属配合物。分别采用光谱分析、热分析及X射线衍射测试技术对产物进行了表征和测试。结果表明,连接偶氮苯和金属配合物之间碳链的长度对该化合物的相转变和荧光特性具有特殊的影响。该系列化合物在紫外光和热作用下具有99%以上的偶氮苯顺-反异构化反应效率;具有290和560 nm这2个波段的荧光发射光谱。由其中1个金属配合物分散在聚甲基丙烯酸甲酯网络而形成的介质可作为全息信息存储材料而实现全息图像的写入和读出。  相似文献   

13.
2‐Deoxy sugars and their derivatives occur abundantly in many pharmaceutically important natural products. However, the construction of specific 2‐deoxy‐glycosidic bonds remains as a challenge. Herein, we report an efficient way to prepare 2‐deoxy‐α‐glycosides by glycosylation of 2‐iodo‐glycosyl acetate and subsequent visible‐light‐mediated tin‐free reductive deiodination. We have successfully applied the postglycosylational‐deiodination strategy in the synthesis of more than 30 mono‐, di‐, tri‐, tetra‐ and pentadeoxysaccharides with excellent stereoselectivity and efficiency. This method has also been applied to the synthesis of a 2‐deoxy‐tetrasaccharide containing four α‐linkages.  相似文献   

14.
徐洪耀  李晟  邵宗龙  胡蕾 《合成化学》2007,15(3):270-274
采用酰氯酯化法,通过对烯丙氧基苯甲酰氯与胺基偶氮苯反应,合成了6个含偶氮苯非线性光学生色团的末端烯,其结构经1H NMR, IR和元素分析表征.  相似文献   

15.
含偶氮苯的咔唑类双功能光折变聚合物的合成及表征   总被引:1,自引:1,他引:1  
通过后重氮偶合方法制备了一系列不同生色团含量的咔唑类双功能光折变聚合物,并用IR、^1H-NMR、UV-vis、DSC以及GPC等对聚合物进行了分析和表征。IR和UV-vis谱图显示偶氮苯基团已接到咔唑环上。UV-vis结果表明:反应时间对该反应的影响非常大,当反应时间从6h增加到60h时,聚合物中生色团的含量从13.5%升高到66.7%。GPC结果显示后重氮偶合法比常规方法得到的该类聚合物的分子量明显提高。DSC结果显示聚合物的玻璃化转变温度随偶氮苯含量的增加而升高。  相似文献   

16.
Along with the O- and C-aryl glycosides, N-aryl glycosides represent an important class of carbohydrate and heterocyclic aryl conjugates that possess diverse applications and implications of biological interest. However, most of the synthetic efforts have been directed toward the preparation of O- and C-aryl glycosides. This review focuses on the various strategies that have been employed to synthesize N-aryl glycosides, most of which developed in the past 20 years. Besides having their unique applications, these N-aryl glycosides can also be treated as the analogs of O- and C-aryl glycosides. Wide ranges of reaction conditions are discussed for the optimum conditions.  相似文献   

17.
采用偶氮偶联和金属钯催化偶联反应法,合成了一系列非线性光学基团直接取代乙炔化合物,其结构经^1HNMR,IR,DSC及元素分析等表征。  相似文献   

18.
A new photochromic biindenylidenedione compound bearing two azobenzene units was synthesized and characterized by means of 1H NMR, 13C NMR, ESI‐MS and elemental analysis. The photochromic and photo‐induced radical properties were investigated by means of UV‐Vis and electron spin resonance spectroscopy, respectively. The results showed that the title compound exhibited photochromic behavior with good fatigue resistances both in solution and in the solid state.  相似文献   

19.
偶氮苯光色基元修饰的杯芳烃的荧光性能和液晶行为;偶氮苯;杯[4]芳烃;热致液晶;荧光  相似文献   

20.
侧基含偶氮苯生色团的短梗霉多糖的制备及光致变色性   总被引:2,自引:0,他引:2  
利用4-(4-硝基苯偶氮)-1-萘酚的丙烯酸酯与短梗霉多糖进行接枝共聚,制备了侧基含偶氮苯生色团的短梗霉多糖聚合物,并用红外光谱、扫描电镜、X射线衍射、热重分析等手段对聚合物进行了表征.用紫外光谱研究了聚合物的光致变色性,结果表明聚合物具有良好的热稳定性和光致变色性.  相似文献   

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