The synthesis of new silicon phthalocyanines and analysis of their photochemical and biological properties

•New silicon phthalocyanines.•Singlet oxygen generation.•Photoinactivation of yeast.

In this study, new silicon phthalocyanine compounds were synthesized. The new neutral compound 3 is reacted with excess dimethyl sulfate to obtain quaternized derivative; 3Q. For the synthesis of the zwitterionic complex, 3 and excess 1,3-propanedisultone were reacted in dry dimethylformamide for 24 h under nitrogen atmosphere. The structures of all compounds were characterized by using spectrophotometric techniques. Experiments which include the singlet oxygen generation and photoinactivation of the yeast Saccharomyces cerevisiae both in the absence and presence of light indicated that these compounds can be potentially used in photodynamic therapy or photoinactivation of some microorganisms.

Graphical abstractIn this work, a neutral bis[8-methyl-8-azabicyclo[3.2.1]octan-3-oxy][phthalocyaninato]silicon (3), its quaternized derivative bis[8,8-dimethyl-8-azabicyclo[3.2.1]octan-3-oxy][phthalocyaninato]silicon sulfate (3Q) and bis[8-methyl-8-azabicyclo[3.2.1]octan-3-(N-propanesulfonato)oxy][phthalocyaninato]silicon (3Z) were synthesized and the characterization of all the structures was done by using 1H-NMR, MALDI-TOF, UV–vis and fluorescence spectrometric methods. Photochemical experiments proved that they can be used for PDT. Moreover, photoinactivation of Saccharomyces cerevisiae with the irradiation of 3Q indicated the use of this compound for inactivation of some type of yeast.Figure optionsDownload full-size imageDownload as PowerPoint slide