15086-94-9Relevant articles and documents
Novel β-cyclodextrin-eosin conjugates
Benkovics, Gábor,Afonso, Damien,Darcsi, András,Béni, Szabolcs,Conoci, Sabrina,Fenyvesi, éva,Szente, Lajos,Malanga, Milo,Sortino, Salvatore
, p. 543 - 551 (2017)
Eosin B (EoB) and eosin Y (EoY), two xanthene dye derivatives with photosensitizing ability were prepared in high purity through an improved synthetic route. The dyes were grafted to a 6-monoamino-β-cyclodextrin scaffold under mild reaction conditions through a stable amide linkage using the coupling agent 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride. The molecular conjugates, well soluble in aqueous medium, were extensively characterized by 1D and 2D NMR spectroscopy and mass spectrometry. Preliminary spectroscopic investigations showed that the β-cyclodextrin-EoY conjugate retains both the fluorescence properties and the capability to photogenerate singlet oxygen of the unbound chromophore. In contrast, the corresponding β-cyclodextrin-EoB conjugate did not show either relevant emission or photosensitizing activity probably due to aggregation in aqueous medium, which precludes any response to light excitation.
Heterogeneous inorganic acid/organic acid-salt reaction inside anodic aluminum oxide templates
Al-Kaysi, Rabih O.
, p. 470 - 471 (2010)
Reaction of gaseous HCl with Eosin-Y disodium salt (Eosin-Y-2Na) nanorods nested inside anodic aluminum oxide templates (AAO), produced perforated Eosin-Y free acid (EosinY-FA) nanorods with surface nanoholes on the order of 50 nm in diameter. Diffusion o
Electrophilic bromination in flow: A safe and sustainable alternative to the use of molecular bromine in batch
Van Kerrebroeck, Reinout,Naert, Pieter,Heugebaert, Thomas S.A.,D’hooghe, Matthias,Stevens, Christian V.
, (2019/06/10)
Bromination reactions are crucial in today’s chemical industry since the versatility of the formed organobromides makes them suitable building blocks for numerous syntheses. However, the use of the toxic and highly reactive molecular bromine (Br2) makes these brominations very challenging and hazardous. We describe here a safe and straightforward protocol for bromination in continuous flow. The hazardous Br2 or KOBr is generated in situ by reacting an oxidant (NaOCl) with HBr or KBr, respectively, which is directly coupled to the bromination reaction and a quench of residual bromine. This protocol was demonstrated by polybrominating both alkenes and aromatic substrates in a wide variety of solvents, with yields ranging from 78% to 99%. The protocol can easily be adapted for the bromination of other substrates in an academic and industrial environment.
PROCESS FOR SYNTHESIZING HALOGENATED DERIVATIVES OF FLUORESCEIN FOR USE IN THE PRODUCTION OF NON-VOLATILE MEMORY DEVICES
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Page/Page column 6-7, (2008/06/13)
A process performs solid phase synthesis of halogenated derivatives of fluorescein, and includes reacting fluorescein with a halide MX, wherein M is an alkali metal and X is a halogen, and Oxone? (2 KHSO5.KHSO4.K2SO4), at a temperature higher than or equal to 150° C. A structure uses a halogenated derivative of fluorescein selected from the group consisting of 2′,4′,5′-trichlorofluorescein, 2′,4′,5′,7′-tetrachlorofluorescein, 4′,5′-diiodofluorescein diacetate and 2′,4′,5′-triiodofluorescein as electro-bistable material in a non-volatile memory device.
Synthese d'eosine pure
Fompeydie, Dominique,Onur, Feyyaz,Levillain, Pierre
, p. 5 - 6 (2007/10/02)
According to solubilities of fluorescein and its brominated derivatives, pure eosin (2,4,5,7-tetrabromofluorescein) is prepared with a good yield (about 85 percent) by reaction of Br-/BrO3- on fluorescein in acidic water-acetone mixture.We have determined the exact composition of this medium which allows the precipitation of eosin while the other brominated derivatives of fluorescein remain soluble.
Equilibre entre formes structurales de l'eosine et de la fluoresceine moleculaires. Influence des solvants
Fompeydie, Dominique,Levillain, Pierre
, p. 459 - 465 (2007/10/02)
The study of equilibrium between lactonic and amphoteric forms of molecular eosin and fluorescein proves that, in 11 organic solvents, the lactonic ring of fluorescein is more stable than eosin's while in solid state or in aqueous media, the contrary takes place.The influence of solvents is explained by taking account of their solubility parameters δA and δH.
