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1.
Yukiko Maekawa Makiko Sugiura Atsuko Takeuchi Koji Tomoo Toshimasa Ishida Miyoko Kamigauchi 《Helvetica chimica acta》2010,93(5):991-998
The Advanced Glycation End Products (AGEs) are the causative substances of lifestyle‐habit illness. To elucidate the glycation mechanism of the protein, the reaction of lysozyme with D ‐glucose was analyzed by the fluorescence, TOF‐MS, and 13C‐NMR spectroscopy under the physiological condition. The fluorescence intensity of lysozyme in the glycation solution increased proportionally with a reaction time of ten weeks. The MALDI‐TOF‐MS spectra of the reaction solution after two weeks showed a peak at m/z 15066, which indicated the presence of a larger molecule than the native lysozyme (m/z 14331), and new peaks at m/z 30105 (dimer) and 45000 (trimer) were also observed. The spectral analysis supported the assumption of a continuous glycation reaction of D ‐glucose with lysozyme and a 30% transformation of lysozyme to the dimeric form during ten weeks. The 13C‐NMR spectra of lysozyme showed six [13C]‐labeled signals by the glycation reaction with [13C]‐glucose after two weeks of reaction. The combined analysis of TOF‐MS and 13C‐NMR spectra uncovered that first products of the glycation reaction of lysozyme with D ‐glucose can be observed already three hours after starting the reaction and that nine D ‐glucose units are attached during ten weeks at 37°. 相似文献
2.
Eduardo Soriano Loretta Outler Eric A. Owens Maged Henary 《Journal of heterocyclic chemistry》2015,52(1):180-184
Six novel asymmetrical monomethine cyanine dyes were synthesized via the condensation reaction of 1‐butyl‐2‐(methylthio)benzo[c,d]indol‐1‐ium iodide and various 1,5‐substituted indolenine salts under basic conditions. The dyes were characterized using UV–vis spectroscopy, fluorescence, 1H NMR, 13C NMR, and mass spectrometry; furthermore, the purity of these compounds was observed using LC/ELSD/MS. 相似文献
3.
A series of novel N‐glycosyl‐N′‐pyrazolylmethylene aminothioureas ( 4a‐4e, 5a‐5e ) were synthesized from N‐glycosyl‐N′‐aminothioureas ( 2a‐2d ) and 4‐formylpyrazole ( 3a‐3e ). Activated 4Å molecular sieves were adopted for dehydrated reagent to improve the reaction rate and yield. The structures of the new compounds were identified on the basis of IR, 1H NMR and MS spectra. Simultaneously, the compounds were detected by fluorescence spectrophotometer and had preferable fluorescence activity, so they can be selected as a kind of novel fluorescence labeled derivative of sugar. 相似文献
4.
Unique Fluorogenic Ratiometric Fluorescent Chemodosimeter for Rapid Sensing of CN− in Water
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Dr. Ajit Kumar Mahapatra Kalipada Maiti Saikat Kumar Manna Rajkishor Maji Chitrangada Das Mukhopadhyay Bholanath Pakhira Prof. Sabyasachi Sarkar 《化学:亚洲杂志》2014,9(12):3623-3632
A new benzimidazole‐spiropyran conjugate chemosensor molecule ( BISP ) has been synthesized and characterized by 1H NMR spectroscopy, mass spectrometry (ESI‐MS), and elemental analysis. The two isomeric forms ( BISP ? BIMC ) were shown to be highly selective and sensitive to CN? among the ten anions studied in aqueous HEPES buffer, as shown by fluorescence and absorption spectroscopy and even by visual color changes, with a detection limit of 1.7 μM for BIMC . The reaction of CN? with BIMC was monitored by 1H NMR spectroscopy, high‐resolution mass spectrometry (HRMS), UV/Vis measurements, and fluorescence spectroscopy in HEPES buffer of pH 7.4. TDDFT calculations were performed in order to correlate the electronic properties of the chemosensor with its cyanide complex. Further, titration against thiophilic metal ions like Au3+, Cu2+, Ag+, and Hg2+ with [ BIMC‐CN ] in situ showed that it acts as a secondary recognition ensemble toward Au3+ and Cu2+ by switch‐on fluorescence. In addition, a reversible logic‐gate property of BIMC has been demonstrated through a feedback loop in the presence of CN? and Au3+ ions, respectively. Furthermore, the use of BIMC to detect CN? in live cells by fluorescence imaging has also been demonstrated. Notably, test strips based on BIMC were fabricated, which could serve as convenient and efficient CN? test kits. 相似文献
5.
Hao Zhang Nianchen Zhou Xing Zhu Xinrong Chen Zhengbiao Zhang Wei Zhang Jian Zhu Zhijun Hu Xiulin Zhu 《Macromolecular rapid communications》2012,33(21):1845-1851
Well‐defined cyclic‐polymers (cyclic‐PAzoMMAs), bearing side‐chain phenylazo naphthalene chromophore, were successfully synthesized by the combination of atom transfer radical polymerization (ATRP) and copper(I)‐catalyzed azide/alkyne cycloaddition “click” reaction, as verified by GPC, 1H NMR, FTIR, and MALDI‐TOF mass spectrometry. The cyclic‐PAzoMMA showed higher glass transition temperatures than the linear‐PAzoMMA with the same molecular weight. Interestingly, the cyclic‐PAzoMMA exhibited deeper modulation depth (M.D.) induced by SRG, larger value of the photoinduced birefringence, increased fluorescence emission, and longer fluorescence lifetime in comparison with its linear counterpart. 相似文献
6.
E,E-1,4-Bis(4'-N,N-diphenylaminostyryl)-2,5-dimethoxybenzene (DPAMOB) has been synthesized by a simple and effective solid phase Wittig reaction and characterized by 1^H NMR spectra and elemental analysis, Linear absorption, single-photon induced fluorescence and two-photon induced fluorescence spectra were experimentally studied. The new dye has a large two-photon absorption (TPA) cross-section of σr= 1007,2 GM [1 GM= 1 × 10^-50 cm^4·s/(photon molecule)] at 800 nm measured by the two-photon induced fluorescence method. The experimental results confirm that DPAMOB is a good TPA chromophore and can successfully initiate two-photon photopolymerization of ethoxylated trimethylolpropane triacrylate esters (SR454). Finally, a microstructure has been fabricated by use of DPAMOB as initiator. 相似文献
7.
Chuan‐Jian Zhou Rui‐Fang Guan Sheng‐Yu Feng David J. Berg Stephen R. Stobart 《中国化学会会志》2005,52(5):947-952
Using the divergent method, carbosilane dendrimers with p‐bromophenyl core were synthesized by using alternating Grignard and hydrosilylation reactions. And then, α‐naphthalenyl was connected to the core by using Suzuki coupling reaction. This gave a new carbosilane dendrimer with a 4‐(naphthalen‐1‐yl)phenyl core. All the products were characterized by IR, 1H NMR, 13C NMR, 29Si NMR, and MS. The study shows that Suzuki Coupling reaction is an effective and powerful core‐functionalization method and a satisfactory result can be achieved through prolonging the reaction time. 相似文献
8.
Wenbin Tan Taohua Leng Guoqiao Lai Zhifang Li Jiefei Wu Yongjia Shen Chengyun Wang 《中国化学》2016,34(8):809-813
A novel and simple fluorescence probe was synthesized from benzo[1,2‐b:4,5‐b′]dithiophene (BDT) and trimethylsilylethyne via Sonogashira reaction, and showed highly selective and sensitive fluorescence decreasing response towards F?. The probe molecule turned to a weakly fluorescent terminal alkyne moiety because its trimethylsilyl (TMS) group was cleaved by fluoride, which was proved by 1H NMR titration. Whereas no distinct fluorescent changes were observed with the addition of other anions, such as Cl?, Br?, I?, AcO? and H2PO4?. Upon the addition of F?, the maximum fluorescence emission wavelength shifted from 460 nm to 450 nm with a decrease of fluorescence intensity by 40% within 20 s. Moreover, the detection limit towards F? was calculated to be as low as 73.5 nmol/L. 相似文献
9.
Four novel [60]fullerene pyrrolidines containing trifluoromethyl (? CF3) group have been synthesized via 1,3‐dipolar cycloaddition reaction, which have been characterized by UV‐Vis spectroscopy, fourier transform infrared spectroscopy, matrix‐assisted laser desorption ionization‐time of flight mass spectroscopy, and 1H, 13C, 19F nuclear magnetic resonance spectrometer (1H NMR, 13C NMR, 19F NMR). Their optical and electrochemical properties have been studied, and the results show that those fulleropyrrolidines containing ? CF3 group have good fluorescence and electrochemical properties. Compared with C60, they have negative shifts in varying degrees for half‐wave potentials, and may have potential applications for photovoltaic conversion materials since their lowest unoccupied molecular orbital (LUMO) levels are close to that of [6,6]‐phenyl‐C61‐butyric acid methyl ester. 相似文献
10.
Hai‐Sub Na Yasuhiro Morisaki Yasuhiro Aiki Yoshiki Chujo 《Journal of polymer science. Part A, Polymer chemistry》2007,45(14):2867-2875
Novel π‐conjugated polymers ( 8 – 10 ) were prepared by the palladium‐catalyzed Sonogashira coupling reaction of three kinds of phosphole‐ring‐containing monomers with 2,5‐dihexyloxyl‐1,4‐diethynylbenzene. The obtained polymers ( 8 – 10 ) were regioregulated with the 2,5‐substituted phosphole ring in the polymer main chain and characterized with 1H, 13C, and 31P NMR and FTIR. Polymers 8 – 10 were found to have an extended π‐conjugated system according to the results of UV–vis absorption spectra. In the fluorescence emission spectra of 8 – 10 , moderate emission peaks were observed in the visible blue‐to‐green region. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2867–2875, 2007 相似文献
11.
Kinetics of the Same Reaction Monitored over Nine Orders of Magnitude in Concentration: When Are Unique Subensemble and Single‐Turnover Reactivity Displayed?
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Dr. Quinn T. Easter Prof. Suzanne A. Blum 《Angewandte Chemie (International ed. in English)》2018,57(37):12027-12032
Essentially no information is known about the behavior of individual molecular catalysts under reaction conditions. This is a result of the averaging inherent to traditional analytical techniques. Herein, a combined fluorescence microscopy and 1H NMR spectroscopy study reveals that unique (that is, non‐ensemble averaged) distributions and time‐variable kinetics from molecular ruthenium catalysts within growing polynorbornene occur and are detectable between 10?9 m and 10?6 m of substrate, surprisingly just 1000‐fold less concentrated than a typical laboratory bench‐scale reaction. The kinetic states governing single‐turnover events are determinable by overlay of the signal arising from individual monomer insertion reactions with that from polymer growth from neighboring catalysts. 相似文献
12.
Dr. Jiyoung Jung Junyong Jo Moitree Laskar Prof. Dr. Dongwhan Lee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(16):5156-5168
A series of C2‐symmetric chiral tetra‐dentate ligands were prepared by using [4,5]‐ or [5,6]‐pinene‐fused 2,2′‐bipyridyl units that are supported across a rigid arylene–ethynylene backbone. These conformationally pre‐organised chelates support stable 1:1 metal complexes, which were fully characterised by UV/Vis, fluorescence, circular dichroism (CD), and 1H NMR spectroscopy. A careful inspection of the exciton‐coupled circular dichroism (ECCD) and 1H NMR spectra of the reaction mixture in solution, however, revealed the evolution and decay of intermediate species en route to the final 1:1 metal–ligand adduct. Consistent with this model, mass spectrometric analysis revealed the presence of multiple metal complexes in solution at high ligand‐to‐metal ratios, which were essentially unobservable by UV/Vis or fluorescence spectroscopic techniques. Comparative studies with a bi‐dentate model system have fully established the functional role of the π‐conjugated ligand skeleton that dramatically enhances the thermodynamic stability of the 1:1 complex. In addition to serving as a useful spectroscopic handle to understand the otherwise “invisible” solution dynamics of this metal–ligand assembly process, temperature‐dependent changes in the proton resonances associated with the chiral ligands allowed us to determine the activation barrier (ΔG≠) for the chirality switching between the thermodynamically stable but kinetically labile (P)‐ and (M)‐stereoisomers. 相似文献
13.
Yi Qin Ying Zhang Guangqiang Yin Yuxuan Wang Changwei Zhang Lijun Chen Hongwei Tan Xiaopeng Li Lin Xu Haibo Yang 《中国化学》2019,37(4):323-329
Photoswitchable or photoactivatable fluorescent species have been found wide applications within supramolecular chemistry and materials science. In this study, we successfully constructed two highly emissive Pt(II) metallacycles from the diarylethene ligands via coordination‐driven self‐assembly. Different from the most known fluorescent metallacycles, the obtained metallacycles have displayed “turn‐on” fluorescence switching. They are non‐fluorescent in solution, but they emit highly yellow or orange fluorescence under ultraviolet irradiation. The metallacycles were well characterized by 1H NMR, 31P NMR and ESI‐TOF‐MS. The photochromic properties of the resultant metallacycles were investigated by 1H NMR, 31P NMR, UV/Vis spectrum and fluorescence spectrum. Notably, NMR studies revealed that these two metallacycles featured excellent cyclization efficiency (90% conversion efficiency). Moreover, the closed‐ring isomers of the metallacycles displayed relatively high quantum yield (ΦF = 0.5). DFT simulations demonstrated that the antiparallel configuration of the diarylethene ligand had an angle closed to 120°, which was more stable in energy compared to the parallel configuration, thus allowing for the facile construction of highly emissive metallacycles. We believe that such highly emissive metallacycles which are in‐situ prepared upon irradiation can be used as new fluorescence materials for sensing and bioimaging in the future. 相似文献
14.
Synthesis of New Chlorin e6 Trimethyl and Protoporphyrin IX Dimethyl Ester Derivatives and Their Photophysical and Electrochemical Characterizations
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Dr. José C. J. M. D. S. Menezes Prof. M. Amparo F. Faustino Prof. Kleber T. de Oliveira Dr. Marciana P. Uliana Prof. Vitor F. Ferreira Dr. Steffen Hackbarth Prof. Beate Röder Dr. Thiago Teixeira Tasso Dr. Taniyuki Furuyama Prof. Nagao Kobayashi Prof. Artur M. S. Silva Prof. M. Graça P. M. S. Neves Prof. José A. S. Cavaleiro 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(42):13644-13655
In view of increasing demands for efficient photosensitizers for photodynamic therapy (PDT), we herein report the synthesis and photophysical characterizations of new chlorin e6 trimethyl ester and protoporphyrin IX dimethyl ester dyads as free bases and ZnII complexes. The synthesis of these molecules linked at the β‐pyrrolic positions to pyrano[3,2‐c]coumarin, pyrano[3,2‐c]quinolinone, and pyrano[3,2‐c]naphthoquinone moieties was performed by using the domino Knoevenagel hetero Diels–Alder reaction. The α‐methylenechromanes, α‐methylenequinoline, and ortho‐quinone methides were generated in situ from a Knoevenagel reaction of 4‐hydroxycoumarin, 4‐hydroxy‐6‐methylcoumarin, 4‐hydroxy‐N‐methylquinolinone, and 2‐hydroxy‐1,4‐naphthoquinone, respectively, with paraformaldehyde in dioxane. All the dyads as free bases and as ZnII complexes were obtained in high yields. All new compounds were fully characterized by 1D and 2D NMR techniques, UV/Vis spectroscopy, and HRMS. Their photophysical properties were evaluated by measuring the fluorescence quantum yield, the singlet oxygen quantum yield by luminescence detection, and also the triplet lifetimes were correlated by flash photolysis and intersystem crossing (ISC) rates. The fluorescence lifetimes were measured by a time‐correlated single photon count (TCSPC) method, fluorescence decay associated spectra (FDAS), and anisotropy measurements. Magnetic circular dichroism (MCD) and circular dichroism (CD) spectra were recorded for one ZnII complex in order to obtain information, respectively, on the electronic and conformational states, and interpretation of these spectra was enhanced by molecular orbital (MO) calculations. Electrochemical studies of the ZnII complexes were also carried out to gain insights into their behavior for such applications. 相似文献
15.
Shengxiong Xiao Shu Wang Hongjuan Fang Yuliang Li Zhiqiang Shi Chimin Du Daoben Zhu 《Macromolecular rapid communications》2001,22(16):1313-1318
Poly(phenylenevinylene) (PPV) derivatives covalently linked to fullerene C60 (PPV‐1‐C60 and PPV‐2‐C60) were synthesized by cycloaddition reaction between C60 and azide group‐containing PPV derivatives. By tuning the initial feed ratio of the azido monomer, the content of C60 in the copolymers was controlled. The copolymers were partially soluble in common organic solvents and were characterized by means of 1H NMR, FT‐IR, UV‐Vis and fluorescence spectroscopy, as well as by GPC, TGA and cyclic voltammetry techniques. 相似文献
16.
Synthesis of New 1,2,3‐Triazole Derivatives Possessing 4H‐Pyran‐4‐one Moiety by 1,3‐Dipolar Cycloaddition Reaction of Azidomethyl Phenylpyrone with Various Alkynes
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Mahnaz Saraei Bagher Eftekhari‐Sis Massomeh Faramarzi Roshanak Hossienzadeh 《Journal of heterocyclic chemistry》2014,51(5):1500-1503
A series of new 1,2,3‐triazole derivatives were synthesized by 1,3‐dipolar cycloaddition reaction of 2‐(4‐azidomethylphenyl)‐6‐phenyl‐4H‐pyran‐4‐one with different alkynes in 40–71% yields. In the case of terminal alkynes, the reaction was proceeded in the presence of Cu(I) catalyst. The structure of the synthesized compounds were confirmed by FTIR, 1H‐NMR, and 13C‐NMR spectroscopy and elemental analysis. 相似文献
17.
The reactions of hexachlorocyclotriphosphazene N3P3Cl6 ( 1 ) with 1‐naphthol and 1‐naphthylamine have been examined. The reaction of 1 with sodium 1‐naphthoxy gave the hexakis(1‐naphthoxy)cyclotriphosphazene ( 2 ) in high yield. Geminal 2,2‐di(1‐naphthylamino)‐4,4,6,6‐tetrachlorocyclotriphosphazene ( 3 ) was obtained from the reaction of 1 with 1‐naphthylamine. The structures of phosphazene derivatives were defined by elemental analysis, FTIR, UV‐‐visible, and 1H, 13C, 31P NMR spectroscopy. The fluorescence intensity of the compounds was measured in THF and CH2Cl2. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:158–162, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20400 相似文献
18.
《Journal of heterocyclic chemistry》2017,54(6):3143-3151
Isoindoline nitroxide‐containing porphyrins were synthesized by the reaction of 5‐phenyldipyrromethane and 5‐(4′‐nitrophenyl)‐dipyrromethane with 5‐formyl‐1,1,3,3‐tetramethylisoindolin‐2‐yloxyl using the Lindsey method. These spin‐labeled porphyrins were further characterized by MS, UV, FTIR, 1H‐NMR, cyclic voltammetry, electron paramagnetic resonance (EPR), and fluorescence spectroscopy. The electrochemical assay demonstrated that these isoindoline nitroxides‐containing porphyrins had similar electrochemical and redox properties as 5‐carboxy‐1,1,3,3‐tetramethylisoindolin‐2‐yloxyl. Electron paramagnetic resonance test exhibited these porphyrins possessed the hyperfine splittings and characteristic spectra of isoindoline nitroxides, with typical nitroxide g‐values and nitrogen isotropic hyperfine coupling constants. Fluorescence spectroscopy revealed that these porphyrins indicated fluorescence suppression characteristic of nitroxide–fluorophore systems. Moreover, their reduced isoindoline nitroxide‐containing porphyrins eliminated the fluorescence suppression and displayed strong fluorescence. Thus, these isoindoline nitroxide‐containing porphyrins may be considered as the potential fluorescent and EPR probes. 相似文献
19.
Reaction‐Based Fluorescent Probe for Detection of Endogenous Cyanide in Real Biological Samples
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Dr. Lingliang Long Lin Wang Yanjun Wu Prof. Aihua Gong Dr. Zulin Da Prof. Chi Zhang Zhixiang Han 《化学:亚洲杂志》2014,9(11):3291-3298
Herein, two compounds ( 1 a and 1 b ) were rationally constructed as novel reaction‐based fluorescent probes for CN? by making use of the electron‐withdrawing ability of the cyano group that was formed from the sensing reaction. Notably, this design strategy was first employed for the development of fluorescent CN? probes. The experimental details showed that probe 1 a exhibited a fluorescence turn‐on response to CN?, whereas other anions, biological thiols, and hydrogen sulfide gave almost no interference. The detection limit of probe 1 a for CN? was found to be 0.12 μM . The sensing reaction product of 1 a with CN? was characterized by NMR spectroscopy and mass spectrometry. TD‐DFT calculations demonstrated that the formed cyano group drives the intramolecular charge transfer (ICT) process from coumarin dye to the cyano group and thus the original strong ICT from the coumarin dye to the 3‐position pyridyl vinyl ketone substituent is weakened, which results in recovery of coumarin fluorescence. The practical utility of 1 a was also examined. By fabricating paper strips, probe 1 a can be used as a simple tool to detect CN? in field measurements. Moreover, probe 1 a has been successfully applied for quantitative detection of endogenous CN? from cassava root. 相似文献
20.
Xiao‐Xi Hu Peng‐Hui Li Kelvin W. K. Yeung Paul K. Chu Shui‐Lin Wu Zu‐Shun Xu 《Journal of polymer science. Part A, Polymer chemistry》2010,48(24):5961-5967
A complex of Eu3+, acrylic acid (AA), and 1, 10‐phenanthroline (Phen) was synthesized. The structure and fluorescence of Eu(AA)3Phen was characterized with elemental analysis, FTIR, 1H NMR, and fluorescence spectroscopy. A novel copolymer containing rare earth complex, poly(PEGMA‐co‐NIPAm‐co‐Eu(AA)3Phen) (PPNEu), was prepared by free radical copolymerization in methanol with azodiisobutyronitrile as initiator. 1H NMR, fluorescence spectroscopy, UV‐vis spectroscopy, and TEM were used to characterize this copolymer. The interaction of PPNEu with deoxyribonucleic acid (DNA) was studied by fluorescence spectroscopy, UV‐vis spectroscopy and agarose gel electrophoresis. The results of fluorescence, UV‐vis absorption, and agarose electrophoresis indicated that the PPNEu could interact with DNA in an electrostatic bonding mode. The TEM observation showed that the PPNEu could form spherical micelles in water solution small than 100 nm; the efficient complexation of PPNEu with DNA occurred. These results suggested the potential of the PPNEu as gene detective reagent and gene delivery carrier. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献