Modifications of Porphyrins and Hydroporphyrins for their Solubilization in Aqueous Media

Abstract

Abstract:The increasing popularity of porphyrins and hydroporphyrins for application in a variety of biomedical (photodynamic therapy, fluorescence tagging and imaging, photoacoustic imaging) and technical (chemosensing, catalysis, light harvesting) applications is also associated with the growing number of methodologies that enable their solubilization in aqueous media. Natively, the vast majority of synthetic porphyrinic compounds are not water-soluble. Moreover, any water-solubility imposes several restrictions on the synthetic chemist on when to install solubilizing groups in the synthetic sequence, and how to isolate and purify these compounds. This review summarizes the chemical modifications to render synthetic porphyrins water-soluble, with a focus on the work since 2000. Where available, practical data such as solubility, indicators for the degree of aggregation, and special notes for the practicioner are listed. We hope that this review will guide synthetic chemists through the many strategies known to make porphyrins and hydroporphyrins water soluble.

Molecular Photoacoustic Contrast Agents: Design Principles & Applications

“…(Fig. 51 ) . A multifold contrast enhancement in PA amplitude was reported in comparison with the ICG dye attributed to a short triplet lifetimes, low fluorescence quantum yield.…”

“…Structure of the water‐soluble NIR absorbing tetra‐ PEG ‐ylated quinolone‐annulated porphyrin 51 reported by Luciano et al . .…”

Oxazolochlorins 21. Most Efficient Access to meso-Tetraphenyl- and meso-Tetrakis(pentafluorophenyl)porpholactones, and Their Zinc(II) and Platinum(II) Complexes

“…While several phenyl- and substituted phenyl-derivatives were reported [ 3 , 4 ], the by far most popular derivative is the meso -tetrakis(pentafluorophenyl)porpholactone (T F PL) and its metal complexes (T F PLM) [ 1 , 5 , 6 ]. This is because of their relative ease of synthesis in one step from T F PP using a number of different methodologies (see below Scheme 2 ) and the multiple possibilities to derivatize the C 6 F 5 -groups by means of nucleophilic aromatic substitution reactions to, for example, render them water-soluble [ 6 , 7 , 8 ]. The presence of a ß,ß’-lactone moiety in carbaporphyrins [ 9 ], thiaporphyrins [ 10 , 11 ], octaalkylporphyrins [ 12 ], or subporphyrins [ 13 ] is known but much more rare and the utility of these compounds has not yet been shown.…”

Simple, Axial Ligand-Mediated Route to Water-Soluble Iridium Corroles

“… 20 − 28 A number of these applications, especially in the biomedical sphere, require water-soluble derivatives of the complexes, which are typically accessible via cumbersome synthetic and purification steps. 2 , 29 , 30 A recent reinvestigation of iridium corroles (in which 4-picolinic acid derivatives were found to be partially water-soluble) suggested that the use of water-soluble axial ligands might afford a simple, one-pot route to water-soluble Ir corroles as a new class of singlet oxygen photosensitizers. 31 The beguilingly simple exercise, however, threw up unexpected challenges.…”