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Creators/Authors contains: "Vicente, M. Graça"

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  1. Novel tetraaryl-(pyridinium-4-yl)-tetrabenzoporphyrins have been successfully synthesized via a Heck-based sequence reaction. These tetrabenzoporphyrins were substituted with eight pyridyl groups at the fused benzene rings. Methylation of the pyridyl groups with methyl iodide afforded highly water soluble tetrabenzoporphyrins carrying eight ionic groups. The extended [Formula: see text]-conjugation broadened and red-shifted the absorption band of these porphyrins to 650–750 nm. These cationic tetrabenzoporphyrins showed non-toxicity in the dark up to 100 uM. High phototoxicity with IC[Formula: see text] values lower than 18 [Formula: see text]M were obtained for these tetrabenzoporphyrins. 
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  2. A 1,3,5,7-tetramethyl-8-(2,4,6-triphenylphenyl)-BODIPY and its 2,6-dichloro derivative were synthesized and their spectroscopic properties compared experimentally and computationally with those of the corresponding 8-phenyl and 8-mesityl derivatives. The new 2,6-dichloro-1,3,5,7-tetramethyl-8-(2,4,6-triphenylphenyl)-BODIPY shows the highest fluorescence quantum yields in dichloromethane and toluene. 
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  3. Subphthalocyanine (SubPc) macrocycles are known as an interesting class of nonplanar aromatic dyes. Despite documented high fluorescence and singlet oxygen quantum yields, the properties of SubPcs in photodynamic therapy (PDT) are underestimated, because their absorption bands do not reach a significant wavelength range. With this in mind, we combined a SubPc ring and a SubPc ring by introducing a common benzene ring and obtained a SubPc dimer (2) and trimer (3) with the Q-band at the near-IR region, owing to the expansion of the [Formula: see text] electron conjugated system. In this study, we reported 1 O 2 generation abilities of 2 and 3based on the applied absolute singlet oxygen quantum yields ([Formula: see text] absolute ). Subsequent research revealed that 2 and 3 showed the potential to generate 1 O 2 to not only in toluene but also in DMSO. Although the photocytotoxicity of 2 and 3 were investigated upon photo-irradiation with a low light dose of approximately 1.5 J/cm 2 , 2 and 3 showed almost negligible toxic properties toward HEp2 cells. 
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