Azides and Porphyrinoids: Synthetic Approaches and Applications. Part 2-Azides, Phthalocyanines, Subphthalocyanines and Porphyrazines

The reaction between organic azides and alkyne derivatives via the Cu(I)-catalyzed azide–alkyne cycloaddition (CuAAC) is an efficient strategy to combine phthalocyanines and analogues with different materials. As examples of such materials, it can be considered the following ones: graphene oxide, carbon nanotubes, silica nanoparticles, gold nanoparticles, and quantum dots. This approach is also being relevant to conjugate phthalocyanines with carbohydrates and to obtain new sophisticated molecules; in such way, new systems with significant potential applications become available. This review highlights recent developments on the synthesis of phthalocyanine, subphthalocyanine, and porphyrazine derivatives where CuAAC reactions are the key synthetic step.

Assessing Amphiphilic ABAB Zn(II) Phthalocyanines with Enhanced Photosensitization Abilities in In Vitro Photodynamic Therapy Studies Against Cancer

We have previously demonstrated that singlet oxygen photosensitization abilities of Zn(II) phthalocyanines (Zn(II)Pcs) are enhanced through α-functionalization with bulky fluorinated substituents (i.e., bis(trifluoromethyl)phenyl units) at facing positions of ABAB Zn(II)Pcs, where A and B refer to differently functionalized isoindoles. In this work, we have prepared the Zn(II)Pc ABAB 1 endowed with hydrophilic triethylene glycol monomethyl ether (i.e., at the A isoindoles) to provide solubility in aqueous media, together with its A₃B and A₄ counterparts, and compared their ability to behave as photosensitizers for photodynamic therapy. All photophysical data, aggregation studies and preliminary in vitro biological assays in cell cultures of SCC-13 (squamous cell carcinoma) and HeLa (cervical cancer cells), have proved ABAB 1 as the best photosensitizer of the series.

Fluorine-substituted tetracationic ABAB-phthalocyanines for efficient photodynamic inactivation of Gram-positive and Gram-negative bacteria

Herein, we report the synthesis and characterization of new amphiphilic phthalocyanines (Pcs), the study of their singlet oxygen generation capabilities, and biological assays to determine their potential as photosensitizers for photodynamic inactivation of bacteria. In particular, Pcs with an ABAB geometry (where A and B refer to differently substituted isoindole constituents) have been synthesized. These molecules are endowed with bulky bis(trifluoromethylphenyl) groups in two facing isoindoles, which hinder aggregation and favour singlet oxygen generation, and pyridinium or alkylammonium moieties in the other two isoindoles. In particular, two water-soluble Pc derivatives (PS-1 and PS-2) have proved to be efficient in the photoinactivation of S. aureus and E. coli, selected as models of Gram-positive and Gram-negative bacteria.

The synthesis and investigation of photochemical, photophysical and biological properties of new lutetium, indium, and zinc phthalocyanines substituted with PEGME-2000 blocks

Zinc(II) (5), indium(III) (6), and lutetium(III) (7) phthalocyanines (Pcs) peripherally substituted with poly (ethylene glycol) (PEG) monomethyl ether 2000 (PEGME-2000) blocks were synthesized via Sonogashira coupling reaction with high yields and their photophysical, photochemical and photobiological properties were investigated. We elucidated the interactions of these compounds with calf thymus DNA and bovine serum albumin (BSA), and determined K_(DNA) and K_(BSA) binding constants at degrees of 10⁵ and 10⁶, respectively. Singlet oxygen quantum yields were found (Ф_∆ = 0.44, 0.54, and 0.68 for 5, 6, and 7, respectively). Thermodynamic parameters, as well as thermal denaturation profile of double-stranded CT-DNA were examined to determine the type of binding mode. According to our experimental data, we report that PEGME-2000 favors the formation of binary complex between DNA, and phthalocyanine complexes. Therein, thermodynamic data suggest that this binding mode is indeed spontaneous under reported conditions, and rather non-specific. Additionally, Pcs 5, 6, and 7 substituted with PEGME-2000 blocks showed antimicrobial activity against Gram-positive and Gram-negative bacteria, as well as fungi (yeast), and Pc 5 had the highest antimicrobial activity among them, as revealed by disc diffusion assay results. In short, our results suggest that these compounds could be used for photodynamic therapy, they have both antibacterial and antifungal activity, and the binding ability of new phthalocyanines 5, 6, and 7 with BSA paves the way for their utilization as drug vehicle in blood plasma.

Dual-directional alkyne-terminated macrocycles: Enroute to non-aggregating molecular platforms

Derivatized phthalocyanines (Pcs) and their heteroatom analogues, azaphthalocyanines (AzaPcs), bearing a variety of highly active ligands, have many advantageous properties that make them suitable as novel macrocyclic platforms.

Novel environmentally sustainable cardanol-based plasticizer covalently bound to PVC via click chemistry: synthesis and properties

Cardanol, a famous renewable organic resource of the cashew industry, was covalently linked to PVC chains as a natural internal plasticizer using the click reaction. The modified PVC exhibited decreased T_g and near-zero migration.

A novel approach to synthesize polymers for potential photodynamic therapy: from benzenedinitrile to phthalocyanine

RAFT synthesized polymers with benzenedinitrile side chains were converted to phthalocyanine conveniently, providing a novel method for making PDT polymers.