Catalysis photodynamic therapy

The preparation of nickel porphyrins, difficult by other methods including the Suzuki reaction, can readily be assembled using this methodology [122]. Thus, 347 could be coupled with alkynylpyridine 340 to produce porphyrin 348. The resultant compounds have found utility in photodynamic therapy, catalysis, or exhibit unique electrical properties. 

The interaction of artificial metal ions/complexes with peptides/proteins [11], nucleic acids/DNA [12,13], enzymes [14], steroids [15] and carbohydrates [16] forms a bridge between natural and artificial macromolecular metal complexes. Biometal-organie chemistry concentrates on such complexes [17]. The reason for the increasing interest in this field lies in medical applications of metal complexes (cancer, photodynamic therapy of cancer, immunoassays, fluorescence markers, enantioselective catalysis, template orientated synthesis of peptides, etc.). Figure 2-4 presents an overview of metals in medicine [18]. Some examples are given below. 

Porphyrins and phthalocyanines can be used as core, branches, and terminal groups of dendrimers that have been extensively used as bio-inspired models or mimics of natural systems such as hemoproteins and chlorophyll in photosynthesis, but also in host-guest chemistry, biosensors, photodynamic therapy, and catalysis. Aida et al. demonstrated the amplitude of this field in a review of 2009 [98]. In the following paragraphs, some historical backgrounds will be presented before focusing in a topic specifically concerned on the porphyrin-dendrimer electrochemistry and photoinduced electron transfer processes. 

The mew-substituted porphyrins, though not naturally occurring, are widely preferred candidates in various fields such as biomimetic models, materials chemistry, photodynamic therapy, catalysis, electron transfer, etc. [180]. The synthesis of these derivatives is much simpler compared to their -substituted counterparts. Rothenmund et al. prepared the first mew-tetramethyl porphyrin derivative by the condensation of acetaldehyde and pyrrole [181]. A side-product chlorin , a porphyrin-related macrocycle, which is largely, but not completely aromatic in nature, is usually formed in this reaction. However, chlorins can be easily oxidized to form the corresponding porphyrins. Alder et al. developed a new method in the 1960s to synthesize tetraphenyl derivatives by the condensation reaction of benzaldehyde and pyrrole in the presence of acidic solvents under refluxing... 

Progress in this area has been considerable in recent years and hopefully some non precious metal catalyst will be used in fuel cells in the near future. On the other hand, the stability of metallophthalocyanines makes them appropriate for applications in various fields such as chemical catalysis (such as the MEROX process for the sweetening of oils), dye stuffs, coloring for plastics and metal surfaces, sensors, chromatographic detectors, photoconducting agents, and so on. These complexes are also used for photobiology and photodynamic cancer therapy, electrochemical... 

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