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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Synthesis And Ion Sensing Properties Of Novel Boradiazaindacene Dyes

Zalim, Nalan 01 January 2003 (has links) (PDF)
The derivatives of boradiazaindacene (BODIPY) are highly fluorescent dyes which have quantum yields near 1.0. These dyes that have exceptional spectral and photophysical stability as compared to other fluorescent groups are used for several different applications. The fluorescent sensor molecules for the detection of cations with PET (photoinduced-electron transfer) mechanism in general have been obtained by the differentiation of the BODIPY core. The extension of conjugation over the pyrrole ring shifts the absorption and emission at longer wavelength. Moreover, it is seen that red emission occurs from an ICT (intramolecular-charge transfer) state. iii In this study, we designed and synthesized an unsymetrically substituted BODIPY dye series, carrying a cation-sensitive phenylazacrown ether group conjugated to the core, and investigated the ion sensing properties of these compounds. Both aza-crown derivatives displayed selectivity towards Ca(II).
2

Synthesis and Complexation Studies of Novel Functionalized Crown Ethers and Azacrown Ethers

Huang, Zilin 05 1900 (has links)
Novel cage-functionalized azacrown ethers, i.e. 51, 52, 53, 55, 57, 61 and 62, which have various crown cavity and different number of nitrogen atoms incorporated, have been prepared. X-ray structures of 53, 55 and 57 have been obtained for the study of the crown topological structure. The complexation properties of crown 51, 52, 57, 61 and 62 have been evaluated via alkali metal picrate extraction, silver picrate extraction and ESI-MS study. The novel cage-fuctionalized azacrown ethers generally exhibit high avidity and selectivity towards Ag+ versus alkali metal ions and some transition metals i.e. Cu2+, Mn2+, Zn2+, Ni2+ and Pb2+. Crown 61 displays significant avidity and selectivity toward K+ in alkali metal picrate extraction experiments vis-à-vis the remaining alkali metal picrates. Three types of ditopic ion-exchange receptors for sodium hydroxide extraction study have been designed. All of the crown ether molecules have proper cavity for selective sodium complexation and have weakly acidic ionizable alcohols for sodium-proton exchange under strongly basic conditions. Crown 80 and 81 were synthesized; key intermediates for the synthesis of crown 82, 83 and 84 have been prepared. The preparation of 99 afforded an unexpected crown 103. The preparation of 109 had been attempted, but could not be successfully isolated. Four novel cage-functionalized calix[4]arene crown-5, i.e. 113-116, have been synthesized. The structures of 113 and 116 have been established by X-ray crystal structural analysis and NMR spectral analysis. The complexation properties of the four ionic receptors have been studied via alkali metal picrate extraction experiments. Crown 115 and 116 display more than modest avidity toward alkali metal ions and are most selective toward K+ vis-à-vis 113 and 114.
3

Photoaktivierungsfähige Rhodamine als Bio-Calcium-Sensoren und Markierungen für Tetracystein-Tags in Proteinen / Photoactivable Rhodamines as Bio-Calcium Sensors and Labels for the Tetracysteine-Tags in Proteins

Yan, Sergey 28 January 2011 (has links)
No description available.

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