Zinc(II) phthalocyanine containing Schiff base containing sulfonamide: synthesis, characterization, photophysical, and photochemical properties

New sulfa drug derivatives and their zinc(II) complexes: synthesis, spectroscopic properties and in vitro cytotoxic activities

Synthesis of four sulfa drug derivatives (L1-L4) and Zn(II) complexes derived from sulfonamide group antibiotic substances was carried out using the hydrothermal technique (HT) and their structures of the obtained compounds were explained using elemental analysis (EA), FT-IR and NMR (1H- and 13C-). Cytotoxic activities of four novel sulfa drug based-Schiff base compounds and their Zn(II) complexes were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay using MCF-7 (human breast cancer), Caco-2 (human colorectal adenocarcinoma), A2780 (human ovarian cancer) and LNCaP (human prostate adenocarcinoma) cell lines. LogIC50 values of all obtained compounds were computed with the Graphpad Prism 6 program after 24 h of treatment for MCF-7, Caco-2, A2780 and LNCaP cells. Comet assay experiments were performed using LogIC50 concentrations of all compounds to determine DNA damage. Based on the data obtained, all compounds significantly decreased MCF-7, Caco-2, A2780 and LNCaP cell viability compared to the control groups (p < 0.05).

Comparing Singlet Oxygen Generation of Schiff Base Substituted Novel Silicon Phthalocyanines by Sonophotochemical and Photochemical Applications

Although the sonophotodynamic method has an effective therapeutic outcome for anticancer treatment compared with the photodynamic method, there are not enough related studies in the literature and this study aims to contribute to the development of sonophotodynamic studies. For this purpose, the Schiff base substituted silicon phthalocyanines were designed and synthesized as effective sensitizer candidates and the photophysicochemical and sonophotochemical features of the phthalocyanines were examined to increase singlet oxygen efficiency. The calculated ΦΔ values indicate that the contribution of substituent groups improved the production of singlet oxygen compared with silicon (IV) phthalocyanine dichloride (SiPcCI2 ) and also the sonophotochemical applications increased the singlet oxygen yields. The ΦΔ values (ΦΔ  = 0.76 for axially bis-{4-[(E)-(pyridin-3-ylimino)methyl]phenol} substituted silicon (IV) phthalocyanine (2a), 0.68 for axially bis-4-[(E)-{[(pyridin-3-yl)methyl]imino}methyl]phenol substituted silicon (IV) phthalocyanine (2b) in photochemical study) reached to ΦΔ  = 0.98 for 2a, 0.94 for 2b in sonophotochemical study. This article will enrich the literature on increasing singlet oxygen yield.

Photoantimicrobial activity of Schiff-base Morpholino phthalocyanines against drug resistant micro-organisms in their planktonic and biofilm forms

Antimicrobial photodynamic inactivation (aPDI) is an alternative treatment for the eradication of drug-resistant micro-organisms. One of the advantages of this technique, it that there is no possibility of microbial resistance. Hence, herein, the preparation and characterization of novel neutral and cationic morpholine containing Schiff base phthalocyanines are reported. The cationic complexes (4 and 5) gave moderate singlet oxygen quantum yields (Φ_Δ) of ∼0.2 in aqueous media. Conversely, the neutral complexes generated very low Φ_Δ values making them very poor candidates for antimicrobial studies. The cationic phthalocyanines showed excellent photodynamic activity against planktonic cells of all micro-organisms (Candida albicans, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Salmonella enterica subspecies enterica serovar Choleraesuis, vancomycin-resistant E. faecium, and methicillin-resistant Staphylococcus aureus). The efficiency of aPDI was shown to be both concentration and light-dose-dependent. Mono biofilms were susceptible when treated with 200 µM of cationic Pcs at 108 J/cm². However, ∼10% of the mixed biofilm survived after treatment.

Spectroscopic and photophysicochemical properties of zinc(II) phthalocyanine substituted with benzenesulfonamide units containing schiff base

In this study, compounds (E)-4-((5-bromo-2-hydroxy-3-methoxybenzylidene)amino)-N-(pyridin-2-yl)benzenesul-fonamide 1, (E)-4-((5-bromo-2-(3,4-dicyanophenoxy)-3-methoxybenzylidene)amino)-N-(pyridin-2-yl)benzenesulfonamide 2 and, complex 2(3),9(10),16(17),23(24)-tetra-[(E)-4-((5-bromo-3-methoxy-2-(λ 1-oxidanyl)benzylidene)amino)-N-(pyridine-2-yl)benzenesulfonamide]phthalocyaninato zinc(II) 3 were synthesized for the first time. Their structures (1 –3) were characterized by spectroscopic methods such as FTIR, 1H NMR,13C NMR, UV–vis, MALDI-TOF mass spectra and elemental analysis. The spectroscopic, aggregation, photophysical and photochemical properties of zinc(II) phthalocyanine 3 in dimethyl sulfoxide were investigated and the effects on the above-mentioned properties were reported as a result of the presence of benzenesulfonamide derivatives containing different bioactive groups, in their peripheral positions. In addition, its above-mentioned properties were also reported by comparing different species with those of their substituted and/or unsubstituted counterparts. The zinc(II) phthalocyanine 3 can be a potential photosensitizer candidate in photodynamic therapy, which is an effective alternative therapy in cancer treatment, due to its good solubility in commonly known solvents and monomeric species, as well as its adequate and favorable fluorescence, singlet oxygen production and photostability.

Synthesis, structural characterizations and in vitro cytotoxic activities of new sulfonamide-based Schiff base derivatives

Synthesis of five different new compounds (1-5) were carried out. Their structures were characterized by spectroscopic methods such as Fourier transform infrared, Proton nuclear magnetic resonance, Carbon-13 nuclear magnetic resonance and Elemental analysis. Cytotoxic activities of five new sulfonamide based-Schiff base compounds were determined by MTT assay using A-2780 (human ovarian cancer) and MCF-7 (breast cancer) cell lines. LogIC₅₀ values of the sulfonamide derivates compounds were calculated by Graphpad Prism 12 programme after a 24-hour treatment for A2780 and MCF-7 cells. Comet assay experiments were performed to determine DNA damage using LogIC₅₀ concentrations of all compounds in A2780 and MCF-7 cells. All compounds significantly reduced A2780 and MCF-7 cell viability compared to control groups (p < 0.05). In addition, all compounds caused DNA damage in A2780 and MCF-7 cells (p < 0.05). These results show that the synthesized compounds exhibit cytotoxic effects against cancer cells and that the cause of cell death is due to DNA damage.Communicated by Ramaswamy H. Sarma.