Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.


Issue 6, 2009
Previous Article Next Article

Pd-catalyzed Heck reaction for the synthesis of isomeric metallo tetravinylsulfo phthalocyanines and their photosensitizing properties

Author affiliations

Abstract

Tetrasulfonated zinc phthalocyanine (ZnPcS4) is a potent sensitizer for photodynamic therapy of various medical conditions. Depending on its mode of preparation the material consists of mixtures of ortho and meta sulfonated derivatives as well as regioisomers with different photodynamic potency. To study the effect of the site of substitution on biological parameters that contribute to overall photodynamic efficacy, a series of pure ortho- and meta-tetravinylsulfonated metallo phthalocyanines MPc-o/m-(VS)4 were prepared from the corresponding tetraiodo phthalocyanines using the palladium-catalyzed cross-coupling reaction (Heck reaction). Compared to the tetrasulfonated phthalocyanines, the tetravinylsulfonated derivatives are more hydrophobic and their Q-band absorption maxima are red-shifted. While their in vitro phototoxicity is in the same range as the mixed isomeric sulfonated derivatives, ortho-substituted MPc-o-(VS)4 are more photocytotoxic as compared to their corresponding meta analogs. Although the central metal ion and site of substitution affect aggregation, the tendency to aggregate did not correlate with photodynamic potency nor did overall cell uptake. Instead, intracellular localization at both mitochondrial and lysosomal membranes appears to be the major factor explaining the augmented activity of the ortho substituted derivatives.

Graphical abstract: Pd-catalyzed Heck reaction for the synthesis of isomeric metallo tetravinylsulfo phthalocyanines and their photosensitizing properties

Back to tab navigation

Article information


Submitted
06 Feb 2009
Accepted
03 Apr 2009
First published
17 Apr 2009

Photochem. Photobiol. Sci., 2009,8, 868-874
Article type
Paper

Pd-catalyzed Heck reaction for the synthesis of isomeric metallo tetravinylsulfo phthalocyanines and their photosensitizing properties

H. Ali, N. Cauchon and J. E. van Lier, Photochem. Photobiol. Sci., 2009, 8, 868
DOI: 10.1039/B902530H

Social activity

Search articles by author

Spotlight

Advertisements