Effect of Direct Alkyne Substitution on the Photophysical Properties of Two Novel Octasubstituted Zinc Phthalocyanines

The synthesis of two novel phthalonitrile derivatives (3-4) bearing ethynylcyclohex-1-ene and ethynylcyclohexane groups and two peripherally octa substituted zinc (II) phthalocyanines (5-6) were prepared. The synthesis of phthalonitrile derivatives was performed with Sonagashira coupling reaction by using palladium-catalyzed. The newly synthesized compounds were characterized by using FT-IR, NMR, mass, and UV-Vis absorption spectroscopy techniques. Aggregation studies of 5 and 6 were performed in various organic solvents and different concentrations in tetrahydrofuran (THF). The photophysical studies of the Pcs were performed in THF to determine the effect of the alkyne groups on the fluorescence of the Pc ring. Substances showing fluorescence properties can be used in practical applications such as to create an image in microscopy. Fluorescence quantum yield (ΦF ) and fluorescence lifetime (τF ) of 5-6 were calculated. The fluorescence quenching studies of 5-6 were performed by adding the different concentrations of 1,4-benzoquinone (BQ) to a constant concentration of the Pcs in THF and it was found that benzoquinone was an effective quencher. The values of the Stern-Volmer constant (Ksv ) and quenching constant (kq ) of zinc phthalocyanines (5-6) were examined. All obtained results were compared with each other and with unsubstituted zinc Pc compound used as a reference.

Assessing cytotoxic activities, theoretical and in silico molecular docking calculations of phthalocyanines bearing cinnamyloxy-groups

Cancer has been recognized as one of the deadliest diseases in the world in recent years. By chemically tailoring specific properties, anticancer agents can be prepared very effectively for the treatment of various cancer types. In this manner, as anticancer agents, a series of soluble metal-free and metallophthalocyanines carrying cinnamyloxy-groups at peripheral β-positions have been prepared. All synthesized phthalocyanines were characterized by various spectroscopic approaches such as ultraviolet - visible (UV - Vis), Fourier transform infrared (FT-IR), and matrix-assisted laser deionization/ionization time-of-flight mass spectroscopy (MALDI-TOF MS) techniques. These compounds are highly soluble in dimethyl sulfoxide (DMSO) and soluble in common organic solvents. The spectroscopic properties, cytotoxicity, and theoretical calculations of these complexes have been investigated. In cytotoxicity tests, compounds 1, 4, and 7 are the most active against HT-29 cell lines with IC50 values of 36.9 μM, 32.5 μM, and 51.1 μM, respectively. Also, the most and the least cytotoxic compounds against healthy CCD cell line is compounds 5 and 6 with the IC50 value of 13.4 μM and >250 μM, respectively. The PDB ID:4BQG target protein representing the HT-29 cancer cell line and the anti-cancer activities of phthalonitrile and its phthalocyanines were supported by molecular docking studies. Density Functional Theory (DFT) study supported the experimental results, including the spectral data, and implied that the compounds 5-7 are comparable by their characteristics, such as electronic properties, optical properties, electrostatic potentials, reactivity parameters, with the earlier studied compounds 2-4, which were successfully proved to be good candidates for cancer treatment.Communicated by Ramaswamy H. Sarma.

Sonophotochemical and photochemical efficiency of thiazole-containing metal phthalocyanines and their gold nanoconjugates

This study presents the synthesis of some metal {M = Zn(II), Lu(III), Si(IV)} phthalocyanines bearing chlorine and 2-(4-methylthiazol-5-yl) ethoxy groups at peripheral or axial positions. The newly synthesized metal phthalocyanines were characterized by applying FT-IR, 1H NMR, mass, and UV-Vis spectroscopic approaches. Additionally, the surface of gold nanoparticles was modified with zinc(II) and silicon(IV) phthalocyanines. The resultant nanoconjugates were characterized using TEM images. Moreover, the effect of metal ions and position of substituent, and gold nanoparticles on the photochemical and sonophotochemical properties of the studied phthalocyanines was investigated. The highest singlet oxygen quantum yield was obtained for the lutetium phthalocyanine by applying photochemical and sonophotochemical methods. However, the linkage of the zinc(II) and silicon(IV) phthalocyanines to the surface of gold nanoparticles improved significantly their singlet oxygen generation capacities.

Design of N-heterocycle based-phthalonitrile/metal phthalocyanine-silver nanoconjugates for cancer therapies

This study reports the anticancer properties of carbazole-containing phthalonitrile/phthalocyanine-modified silver nanoparticles for the first time. In this study, a new mono-substituted phthalonitrile namely 3-[9H-carbazole-9-ethoxy]phthalonitrile and its metal phthalocyanines {M = Zn, Co, and Mn(Cl)} were synthesized by template cyclotetramerization of phthalonitrile derivatives. The newly synthesized compounds were characterized using UV-vis, FT-IR, 1H NMR, 13C NMR, and mass spectroscopy. The resultant compounds were successfully linked to the surface of silver nanoparticles. The characterization of the surficial modification was carried out by applying the TEM technique. The cytotoxic activities of the studied nanoconjugates were tested against A549, DLD-1, and Wi38 cell lines by performing a (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay with/without irradiation. Although the functionalization of silver nanoparticles increased the solubility of phthalocyanines in aqueous media, the presence of phthalonitrile/phthalocyanine derivatives on the silver nanoparticles' surface improved their biological properties. All the studied biological candidates exhibited antiproliferative activities against the cell lines. The IC50 values calculated were between 6.80 and 97.99 μM against the studied cell lines in the dark. However, the IC50 values determined were between 3.11 and 88.90 μM with irradiation. The highest IC50 values obtained were 3.11 and 3.52 μM against the DLD-1 cell line for nanoconjugates 1-AgNP and 3-AgNP, respectively. The findings indicated that the compounds may be utilized as anticancer agents after further studies.

Fluorinated Phthalocyanine/Silver Nanoconjugates for Multifunctional Biological Applications

In this study, a new phthalonitrile derivative namely 4-[(2,4-difluorophenyl)ethynyl]phthalonitrile (1) and its metal phthalocyanines (2 and 3) were synthesized. The resultant compounds were conjugated to silver nanoparticles and characterized using transmission electron microscopy (TEM) images. The biological properties of compounds (1-3), their nanoconjugates (4-6), and silver nanoparticles (7) were examined for the first time in this study. The antioxidant activities of biological candidates (1-7) were studied by applying the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The highest antioxidant activity was obtained 97.47 % for 200 mg/L manganese phthalocyanine-silver nanoconjugates (6). The antimicrobial and antimicrobial photodynamic therapy (APDT) activities of biological candidates (1-7) were examined using a micro-dilution assay. The highest MIC value was obtained 8 mg/L for nanoconjugate 6 against E. hirae. The studied compounds and their silver nanoconjugates exhibited high APDT activities against all the studied microorganisms. The most effective APDT activities were obtained 4 mg/L for nanoconjugates (5 and 6) against L. pneumophila and E. hirae, respectively. All the studied biological candidates displayed high cell viability inhibition activities against E. coli cell growth. The biofilm inhibition activities of the tested biological candidates were also investigated against S. aureus and P. Aeruginosa. Biological candidates (1-6) can be considered efficient metal nanoparticle-based materials for multi-disciplinary biological applications.

New phthalonitrile/metal phthalocyanines-gold nanoparticle conjugates for biological applications

The appearance of nanoscience and its effect on the development of the scientific fields particularly materials chemistry have been well-known today. In this study, a new di-substituted phthalonitrile derivative namely...