Antioxidant properties of water-soluble phthalocyanines containing quinoline5-sulfonic acid groups

Abstract

In the present study, the antioxidant properties of peripherally and nonperipherally water-soluble tetra (quinoline 5-sulfonic acid) substituted metal-free (1, 2), Zn(II) (3, 4), Co(II) (5, 6), and Mn(III)Cl (7, 8) phthalocyanine (Pc) derivatives were reported. In order to determine the antioxidant properties of the Pc compounds, three different commonly known antioxidant methods were used: DPPH (α , α-diphenylβ-picrylhydrazyl) radical scavenging, ferrous ion chelating, and reducing power assays. Compound 6 showed the best DPPH activity among the other tested compounds except for the standards. The ferrous ion chelating IC 50 value of compound 7 was nearly as good as that of the EDTA standard. The reducing power activity results indicated that the tested Pc compounds were as sensitive as standard reducing agents such as butylated hydroxytoluene and ascorbic acid. Overall, all tested compounds showed good antioxidant properties and it may be suggested that they could be used as new positive controls for reducing power assays in the future works.

Carbonic anhydrase inhibition and antioxidant activity of the axially naphthoxazin group substituted silicon phthalocyanines

“…The compounds in this study showed higher antioxidant activity compared to the antioxidant activity results of the previously studied axially substituted silicon phthalocyanines (DPPH• SC50 values: DM-C3-Si: 19.9 µg/mL and DE-C3-Si: 23.2 µg/mL, FRAP TEAC values: DM-C3-Si: 232 μM and DE-C3-Si: 73 μM) (Aktaş Karaçelik et al, 2021). When antioxidant activity results of this study were compared with the previously tested PCs within the literature, the SiPcs were in agreement with the literature and even had better antioxidant activity than some PCs (Agirtaş et al, 2019;Günsel et al, 2019;Unluer et al, 2019;Günsel et al, 2020).…”

“…Synthesis and characterization of new phthalocyanine compounds with different functional groups with bioactive properties have been investigated (Yıldırım et al, 2017;Karaçelik et al, 2021a). In addition, in recent years, there has been an increasing interest in these compounds, as phthalocyanine molecules exhibit antioxidant and enzyme inhibition properties according to the metal ion and substituted groups in their center (Demirkapi et al, 2014;Agirtaş et al, 2018;Güzel et al, 2018;Günsel et al, 2019;Demirbaş et al, 2019;Özil et al, 2019;Yakan et al, 2020;Karaçelik et al, 2021;Aktaş Karaçelik et al, 2021).…”

Synthesis, spectroscopic studies, and antioxidant activities of novel thio/carbohydrazones and bis-isatin derivatives from terephthalaldehyde

“…To the previously prepared DPPH solution (4 mL) were added compound solutions of different concentrations (0.25, 0.50, 1.00, 2.50, and 5.00 µM) and enough ethanol to total 5 mL. This mixture was allowed to stand in a dark room at room temperature for 30 min and was then read at 517 nm against a blank [26][27][28][29].…”

Photophysicochemical and Biological Properties of New Phthalocyanines Bearing 4‐(trifluoromethoxy)phenoxy and 2‐(4‐methylthiazol‐5‐yl)ethoxy Groups on Peripheral Positions

“…All the synthesized Pc compounds exhibited DPPH radical scavenging activity. G€ unsel et al(72) studied the antioxidant activity of a series of the newly synthesized Pc compounds using the DPPH free radical scavenging process. According to their findings, the highest DPPH radical capacity was obtained 28.3% inhibition at 500 µg mL À1 .…”