Silicon Phthalocyanines as Anti-infectious, Antioxidant, and Anticancer Agents

This study reports the synthesis of three silicon phthalocyanines (SiPc1-3) bearing 2-dimethylaminoethoxy, 2-[2-(dimethylamino)ethoxy]ethoxy, or 2-{2-[2-(dimethylamino)ethoxy]ethoxy}ethoxy on axial positions. Also, their quaternized derivatives (SiPcQ1-3) were prepared. The effect of ligand length on the biological features of water-soluble silicon phthalocyanines (SiPcQ1-3) was investigated. The highest antimicrobial activity was obtained 32 mu g/mL for SiPcQ1 against double-distilled water, E. hirae, and E. faecalis. The growth inhibition percentages of compounds SiPcQ1-3 were obtained 100 %, 100 %, and 85.14 %, respectively. The highest biofilm inhibition activity was obtained 86.16 % for 250 mg/L SiPcQ3 against S. aureus. The E. coli growth inhibition activities of 50 mg/L compounds SiPcQ1-3 ranged from 60.17 % to 87.53 % and their activities increased (73.46 %-95.37 %) by the enhancement of the concentration. The E. coli viability inhibition activities of SiPcQ1-3 were concentration-dependent. The DNA cleavage and binding properties of SiPcQ1-3 were studied using pBR322 DNA and CT-DNA, respectively. Besides, the toxicity of SiPcQ1-3 was examined against the human colon cancer cell line (DLD-1). The IC50 values of compounds (SiPcQ1-3) were obtained between 10.12 and 27.06 mu M in the dark, however, these values were calculated between 12.32 and 22.17 mu M under the light. SiPcQ3 exhibited the highest in vitro anticancer activity against the tested cell.