- Hexadecabenzyloxy(diphthalocyanines) of rare-earth elements: Synthesis and spectroscopic and electrochemical characteristics
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Reactions of 4,5-dibenzyloxyphthalonitrile with salts of rare-earth elements afforded symmetrical lutetium, dysprosium, samarium, and neodymium complexes with hexadecabenzyloxy(diphthalocyanine), which are well soluble in organic solvents. The spectroscop
- Kalashnikova,Zhukov,Tomilova,Zefirov
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p. 2094 - 2098
(2007/10/03)
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- Synthesis of crowned triazolephthalocyanines
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The synthesis of triazolephthalocyanines bearing crown ether and aza-crown ether substituents is described. Different substituents have been introduced on the nitrogen atom of the aza-crown moiety to improve the solubility and the intrinsic amphiphilic character of these macrocycles. The crowned triazolephthalocyanines described have been prepared by a statistical procedure, and also by different variations of a stepwise method. Preliminary studies of the aggregation properties of one representative of this new family of compounds have also been carried out. An exhaustive study of the synthesis of the corresponding dicyano derivative precursors of the triazolephthalocyanines is displayed. Two different approaches have been used for this goal: The first one inserts the cyano groups prior to the synthesis of the crown ether moiety, while the second one builds the crown ether part of the molecule in advance of the cyanation process. The incompatibility of the Rosemund-von-Braun cyanation conditions and the presence of nitrogen atoms in the molecule is the main difficulty of the synthesis of these pre-cursors.
- Cabezón, Beatriz,Quesada, Ernesto,Esperanza, Sagrario,Torres, Tomás
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p. 2767 - 2775
(2007/10/03)
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- Hydroxyphthalocyanines as potential photodynamic agents for cancer therapy
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A series of benzyl-substituted phthalonitriles, substituted at the 3-, 4-, and 4,5-positions, underwent varied condensations with phthalonitrile to give a series of protected (monohydroxy- and polyhydroxyphthalocyaninato)zinc(II) derivatives which were readily cleaved to give several hydroxyphthalocyanines (ZnPc) (phthalocyanine phenol analogues). Their efficacy as sensitizers for the photodynamic therapy (PDT) of cancer was evaluated on the EMT-6 mammary tumor cell line. In vitro, the 2-hydroxy ZnPc (32) was the most active, followed by the 2,3- and 2,9- dihydroxy ZnPc (39 and 45), with the 2,9,16-trihydroxy ZnPc (33) exhibiting the least activity. In vivo, the monohydroxy derivative 32 and the 2,3- dihydroxy derivative 39 were both efficient in inducing tumor necrosis at 1 μmol kg-1, but complete tumor regression was poor, even at 2 μmol/kg. In contrast, the 2,9-dihydroxy isomer 45, at 2 μmol kg-1, induced tumor necrosis in all animals treated, with 75% complete regression. These results underline the importance of the position of the substituents on the Pc macrocycle to optimize tumor response and confirm the PDT potential of the unsymmetrical Pcs bearing functional groups on adjacent benzene rings.
- Hu, Mougang,Brasseur, Nicole,Zeki Yildiz,Van Lier, Johan E.,Leznoff, Clifford C.
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p. 1789 - 1802
(2007/10/03)
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