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71.
O. S. Kulakovich N. D. Strekal’ M. V. Artem’ev A. P. Stupak S. A. Maskevich S. V. Gaponenko 《Journal of Applied Spectroscopy》2006,73(6):892-896
We have studied enhancement of the fluorescence of fluorescein isothiocyanate (FITC), bound to albumin and near an annealed
silver island film, as a function of the distance between the protein molecules and the metal. As the intermediate spacer
layer between the albumin and the silver substrate, we used multilayer films based on polyelectrolytes. The maximum nine-fold
enhancement coefficient for the fluorescence of FITC corresponds to a thickness of the intermediate layer of ≈4 nm, or three
layers of the polyelectrolyte. In this case, we observe a significant decrease in the average photoluminescence decay time
for the label near the silver film compared with a dielectric medium.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 6, pp. 797–800, November–December, 2006. 相似文献
72.
73.
酰氨基硫脲及其相关化合物通常具有广泛的生物活性 ,如抗菌[1~ 3] ,抑制神经紧张[4] ,治疗血糖过低[5] ,植物生长调节[6~ 9] 等。迄今为止 ,鲜有关于双 (1 ,4 二酰基氨基硫脲 )合成的报道。为了考查该类化合物的生物活性 ,我们设计合成了一系列双 (1 ,4 二酰基氨基硫脲 )化合物 ,以下图所示的两条合成路线合成了该类化合物 :二酰氯 (1 )、异硫腈酸酰酯 (2 )等中间体可不经进一步纯化直接用于下一步反应。所生成的产物 3a 3f、3′d 3′g经DMF H2 O EtOH重结晶 ,产率达 81 %~ 98%。在合成化合物 (1 )时 ,对于一些用SOCl2 … 相似文献
74.
A series of 3-substituted-2-thioxo-2,3-dihydroquinazolin-4(1H)-ones and 6-iodo-3-substituted-2-thioxo-2,3-dihydroquinazolin-4(1H)-ones were synthesized in choline chloride/urea deep eutectic solvent. Substituted 2-mercapto-4(3H)-quinazolinones were synthesized from anthranilic acid or 5-iodoanthranilic acid and appropriate isothiocyanates in good to excellent yields. Isolation of final product was easy and required no further purification. Synthesis of these compounds was rapid, selective, and catalyst free, while preparation of deep eutectic solvent was easy, components are readily available, cheap, and environmentally friendly. 相似文献
75.
J. Lipkowski D. V. Soldatov N. V. Kislykh N. V. Pervukhina Yu. A. Dyadin 《Journal of inclusion phenomena and macrocyclic chemistry》1994,17(4):305-316
A phase diagram of the [Zn(MePy)2(NCS)2]-MePy binary system has been studied by DTA and solubility methods. Two compounds melting incongruently (at 63 and 57°C) have been discovered in the system. They have been obtained as separate phases with crystals of different shape (needles and octahedra). Their composition has been determined by analytical methods and verified by X-ray structural analysis: [Zn(MePy)4(NCS)2]·0.67 MePy·xH2O, wherex depends on the synthesis conditions, and [Zn(MePy)4(NCS)2]·MePy, respectively.The preliminary X-ray study of the first compound (at –100°C) has shown it to be isostructural with the known clathrates of the common formula [M(MePy)4(NCS)2]·0.67MePy·xH2O, where M=Cu, Mn, Mg andx=0–0.33. The unit cell parameters are as follows:a=27.20(1),c=11.202(4) Å, space group
,Z=9.The X-ray study of [Zn(MePy)4(NCS)2]·MePy (at–50°C) has shown it to be analogous to the organic zeolite -phase with the guest MePy molecules located in the channels formed by molecular packing of the [Zn(MePy)4(NCS)2]host. The cell is tetragonal, the space groupI41/a,a=16.845(6),c=23.496(7) Å,V=6667(4) Å3,Z=8,D
calc=1.289 g cm–3,R=0.074. The zinc cation is surrounded by a slightly irregular octahedron of six nitrogen atoms of the MePy and NCS ligands. The crystallisation field of the host [Zn(MePy)4(NCS)2] complex in the temperature range concerned is absent in the phase diagram. It suggests contact stabilization of the [Zn(MePy)4(NCS)2] molecule by the guest in the clathrates.
Supplementary Data relevant to this paper have been deposited with the British Library at Boston Spa, Wetherby, West Yorkshire, U.K. as Supplementary Publication No. SUP 82166 (15 pages). 相似文献
76.
Fatemeh Sheikholeslami-Farahani Zinatossadat Hossaini Faramarz Rostami-Charati 《中国化学快报》2014,25(1):152-154
A straightforward and efficient method for the synthesis of thiopyran derivatives via three-component reaction of alkyl propiolate, benzoylisothiocyanate or its derivatives and α-haloketones in the presence of triphenylphosphine under solvent-free conditions at 70℃ without using any catalyst is reported, The method offers several advantages including high yields of products and an easy work-up procedure. 相似文献
77.
Ryota Seto Kozo Matsumoto Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2013,51(24):5221-5229
Radical copolymerizations of 2‐isothiocyanatoethyl methacrylate (ITEMA) and 2‐hydroxyethyl methacrylate (HEMA) or methacrylic acid (MAA) were examined, and fundamental properties of the obtained copolymers were investigated. The copolymerizations of various ITEMA/HEMA or ITEMA/MAA compositions proceeded effectively in THF or DMF by using 2,2′‐azobisbutyronitrile (AIBN) as an initiator, keeping the isothiocyanato groups and hydroxyl or carboxyl groups unchanged. Glass transition temperatures (Tg)s of poly(ITEMA‐co‐HEMA)s ranged from 68 to 100 °C, and they were thermally stable up to 200 °C. Meanwhile, Tgs of poly(ITEMA‐co‐MAA)s (ITEMA/MAA = 91/9, 76/24) were determined to be 91 and 109 °C, respectively. However, poly(ITEMA‐co‐MAA)s were thermally unstable, and significant weight loss was observed around 180 °C, which may be due to an addition of carboxyl groups to isothiocyanato groups followed by an elimination of COS to form amide structure in the copolymers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 5221–5229 相似文献
78.
A facile and efficient synthesis of 1,5‐benzodiazepines with an arylsulfonamido substituent at C(3) is described. 1,5‐Benzodiazepine, derived from the condensation of benzene‐1,2‐diamine and diketene, reacts with an arylsulfonyl isocyanate via an enamine intermediate to produce the title compounds of potential synthetic and pharmacological interest in good yields (Scheme 1). In addition, reaction of benzene‐1,2‐diamine and diketene in the presence of benzoyl isothiocyanate leads to N‐[2‐(3‐benzoylthioureido)aryl]‐3‐oxobutanamide derivatives (Scheme 2). This reaction proceeds via an imine intermediate and ring opening of diazepine. The structures were corroborated spectroscopically (IR, 1H‐ and 13C‐NMR, and EI‐MS) and by elemental analyses. A plausible mechanism for this type of cyclization is proposed (Scheme 3). 相似文献
79.
Jia-Ming Liu Xiao-Mei Huang Zhen-Bo Liu Fei-Ming Li Zhi-Ming Li Lian-Ying Li 《Analytica chimica acta》2009,648(2):226-182
A new phosphorescent labelling reagent consisting of fullerol, fluorescein isothiocyanate and N,N-dimethylaniline (F-ol-(FITC)n-DMA) was developed. The mode of action is based on the reactivity of the active -OH group in F-ol with the -COOH group of FITC to form an F-ol-(FITC)n-DMA complex containing several FITC molecules. F-ol-(FITC)n-DMA increased the number of luminescent molecules in the biological target of WGA-AP-WGA-F-ol-(FITC)n-DMA (WGA and AP are wheat germ agglutinin and alkaline phosphatase, respectively) which improved the sensitivity using solid substrate room temperature phosphorimetry (SSRTP) detection. The proposed method provided high sensitivity and strong specificity for WGA-AP. The limit of detection (LD) was 0.15 ag AP spot−1 for F-ol and 0.097 ag AP spot−1 for FITC in F-ol-(FITC)n-DMA, which was lower than the method using single luminescent molecules of F-ol-DMA and FITC-DMA to label WGA (0.20 ag AP spot−1 for F-ol-DMA and 0.22 ag AP spot−1 for FITC-DMA). Results for the determination of AP in human serum were in good agreement with those obtained by enzyme-linked immunosorbent assay. The mechanism of F-ol-(FITC)n-DMA labelling of WGA was discussed. 相似文献
80.
This paper involves the preparation of thioureas, which couple with per‐O‐acetylated galactosyl isothiocyanate 1 and 2‐aminobenzothiazole 2 to give incorporating galactosylthiourea derivatives 3. Nucleophilic addition of active primary amine to 3 in the presence of HgCl2 afforded the per‐O‐acetylated guanidinogalactoside 4a‐4d, 5a‐5d, 6a‐6d, 7a‐7d in good yield. These adducts were subjected to deacetylation in MeOH/NaOMe and furnished the corresponding unprotected guanidinogalactosides 8a‐8d, 9a‐9d, 10a‐10d, 11a‐11d. The structures of all newly synthesized compounds were established by IR, 1H NMR, MS and elemental analysis. 相似文献