Magnesium porphyrazinate with eight triphenylphosphonium moieties attached through (2-sulfanyl-ethoxycarbonyl-2-propyl) bridges

Development of AB3-Type Novel Phthalocyanine and Porphyrin Photosensitizers Conjugated with Triphenylphosphonium for Higher Photodynamic Efficacy

There are a number of lipophilic cations that can be chosen; the triphenylphosphonium (TPP) ion is particularly unique for mitochondrion targeting, mainly due to its simplicity in structure and ease to be linked to the target molecules. In this work, mitochondrion-targeted AB₃-type novel phthalocyanine and porphyrin photosensitizers (PSs) were synthesized and their photophysical photochemical properties were defined. Fluorescence quantum yields (Φ_F) are 0.009, 0.14, 0.13, and 0.13, and the singlet-oxygen quantum yields (Φ_Δ) are 0.27, 0.75, 0.57, and 0.58 for LuPcPox(OAc), AB ₃ TPP-Pc, AB ₃ TPP-Por-C4, and AB ₃ TPP-Por-C6, respectively. To evaluate the photodynamic efficacy of the TPP-conjugated PS cell viabilities of A549 and BEAS-2B lung cells were comparatively measured and IC-50 values were determined. AB ₃ TPP-Por-C4, AB ₃ TPP-Por-C6, and AB ₃ TPP-Pc compounds compared to the reference molecules ZnPc and H ₂ TPP were found to be highly cytotoxic (sub-micromolar concentration) under the light. LuPcPox(OAc) is the most effective molecule regarding cell killing (the activity). The cell killing of the TPP-conjugated porphyrin derivatives exhibits a similar response compared to LuPcPox(OAc) when the light absorbing factor of the PS is normalized at 660 nm: TPP-conjugated porphyrins absorb less light (lower extinction coefficient) but produce more radical species (higher singlet-oxygen quantum yield) and therefore effectively kill the cells. The singlet oxygen-producing capacity of AB ₃ TPP-Pc is almost 3 times higher compared to LuPcPox(OAc) and 50% more efficient with respect to ZnPc, suggesting that TPP-conjugated phthalocyanine may serve as a good photosensitizer for photodynamic therapy (PDT). The high singlet oxygen generation capacity of these novel TPP-conjugated porphyrin and phthalocyanine PS suggests that they might be useful for PDT requiring lower photosensitizer concentration and reduced energy deposited through less light exposure.

Partially oxidized porphyrazines

Magnesium porphyrazinate substituted with eight (1-naphthyl) groups on the peripheral positions has been synthesized by cyclotetramerization of 3,4-(1-naphthyl)pyrroline-2,5-diimine, 4-(1-naphthyl)pyrroline-2,5-diimine in the presence of magnesium butanolate. Its demetalation by treatment with trifluoroacetic acid, resulted in a partially oxidized product, namely, octakis(1-naphthyl)-2-seco-porphyrazine-2,3-dione. Further reaction of this product with copper(II) acetate, zinc(II) acetate and cobalt(II) acetate led to the metallo derivatives, [octakis(1-naphthyl)-2-seco-2,3-dioxoporphyrazinato]M(II) ( M = Cu , Zn or Co ). These new compounds have been characterized by elemental analysis, together with FT-IR, 1 H NMR, UV-vis and mass spectral data.

Boronic esters of a porphyrazine and its precursor

Phenylboronic acid esters of an unsaturated precursor 1,2-dicyano-1,2-bis(2-hydroxy- ethylthio)ethylene and the magnesium porphyrazine derived from it have been prepared either by refluxing a mixture of the reagents in chloroform in the presence of molecular sieve or by solvent-free heating in an oven under reduced pressure. The two novel compounds have been characterized by elemental analysis together with ultraviolet-visible, infrared spectroscopy, proton nuclear magnetic resonance, carbon-13 nuclear magnetic resonance, boron-11 nuclear magnetic resonance, and mass spectra.

Seco-porphyrazines with eight (p-tolyl) and (o-tolyl) units

Magnesium porphyrazinates substituted with eight (p-tolyl) and (o-tolyl) units on the peripheral positions have been synthesized for the first time by cyclotetramerization of 1,2-bis(p-tolyl)maleonitrile and 1,2-bis(o-tolyl)maleonitrile in the presence of magnesium butanolate. Their demetalation by the treatment with trifluoroacetic acid resulted in partially oxidized products, namely, octakis(p-tolyl)-2-seco-porphyrazine-2,3-dione and octakis(o-tolyl)-2-seco-porphyrazine-2,3-dione. Further reactions of these products with copper(II) acetate, zinc(II) acetate and cobalt(II) acetate have led to the metallo derivatives, [octakis(p-tolyl)-2-seco-2,3-dioxoporphyrazinato] M(II) and [octakis(o-tolyl)-2-seco-2,3-dioxoporphyrazinato] M(II) ( M = Cu , Zn , Co ). These novel compounds have been characterized by elemental analysis, together with FT-IR, 1H NMR, UV-vis and mass spectral data.

The synthesis and spectral properties of novel porphyrazines with eight (p-tolylmethylthio) and (o-tolylmethylthio) units

By cyclotetramerisation of 1,2-bis(p-tolylmethylthio) and 1,2-bis(o-tolylmethylthio) maleonitrile in the presence of magnesium butanolate, magnesium porphyrazinates carrying eight (p-tolylmethylthio) and (o-tolylmethylthio) units on the peripheral positions have been synthesised. Conversion of the magnesium porphyrazinates into the metal-free derivatives was achieved by treatment with trifluoroacetic acid. Further reactions of these products with copper(ll) acetate, zinc(ll) acetate and cobalt(ll) acetate led to the metal porphyrazinates (M = Cu, Zn, Co).

Octakis (9-anthracenylmethylthio) Iron Porphyrazine Derivatives

Chloro[octakis(9-anthracenylmethylthio)porphyrazinato]iron(III), ([FePzCl]), was prepared by the reaction of metal-free porphyrazine with iron(II) acetate and further treatment with HCl solution. The monomeric bisaxial complex [FePz(py)2] as well as the bridged complex [FePz(pyz)] n were formed as stable complexes by reacting [FePzCl] with pyridine or pyrazine, respectively. These novel complexes were characterised by elemental analysis, together with FT-IR, 1H NMR, UV-Vis and mass spectral data.