Advances in the use of metal-free tetrapyrrolic macrocycles as catalysts

• Mandeep K. Chahal

Beilstein J. Org. Chem. 2024, 20, 3085–3112, doi:10.3762/bjoc.20.257

• applied in various fields, including organometallic catalysis, dye-sensitized solar cells, sensing, artificial olfactory systems, photodynamic therapy (PDT), anticancer drugs, biochemical probes, and electrochemical devices. Relevant examples of these two pyrrolic macrocycles as metal-free organocatalysts

• (1O2) finds many applications in photochemistry and photobiology, e.g., for wastewater treatment, fine chemical synthesis, and photodynamic therapy (PDT) [79][80][81][82][83]. Additionally, after light excitation, porphyrins can also oxidize a substrate by accepting electrons from a substrate molecule

Synthesis and characterization of water-soluble C₆₀–peptide conjugates

• Yue Ma,
• Lorenzo Persi and
• Yoko Yamakoshi

Beilstein J. Org. Chem. 2024, 20, 777–786, doi:10.3762/bjoc.20.71

• photodynamic therapy photosensitizers (PDT PSs) [41] and magnetic resonance imaging contrast agents (MRI CAs) [42], which are the most relevant topics in fullerene biological studies. Aggregated fullerenes in the micelle structure may cause self-quenching of the excited state of PS fullerenes or may inhibit

Synthesis of new representatives of A₃B-type carboranylporphyrins based on meso-tetra(pentafluorophenyl)porphyrin transformations

• Victoria M. Alpatova,
• Evgeny G. Rys,
• Elena G. Kononova and
• Valentina A. Ol'shevskaya

Beilstein J. Org. Chem. 2024, 20, 767–776, doi:10.3762/bjoc.20.70

• biosensors, bioimaging probes, and especially as photosensitizers (PSs) in photodynamic therapy (PDT) [2]. PDT is a treatment modality that uses the combination of a non-toxic PS, oxygen, and light to treat diseases ranging from cancer to age-related macular degeneration and antibiotic-resistant infections

• [3][4][5][6]. Currently, there are a few photosensitizers approved for clinical PDT such as Photofrin®, Foscan®, Lutex®, Tookad®, Purlytin®, Visudyne® and Laserphyrin® [7] and experience in clinical use of PDT shows that this method belongs to one of promising directions in modern clinical oncology

• [8]. Further improvement of the PDT method requires the search for new photosensitizers having higher photoactivity, tumor selectivity, and high singlet oxygen quantum yield, as well as low in vivo toxicity [7]. Therefore, some strategies have been developed to enhance the therapeutic efficiency of

Photoinduced in situ generation of DNA-targeting ligands: DNA-binding and DNA-photodamaging properties of benzo[c]quinolizinium ions

• Julika Schlosser,
• Olga Fedorova,
• Yuri Fedorov and
• Heiko Ihmels

Beilstein J. Org. Chem. 2024, 20, 101–117, doi:10.3762/bjoc.20.11

• also the ability to induce DNA damage upon irradiation [35][36][37][38], and may therefore be considered as promising basis for the development of new reagents for photodynamic (chemo)therapy (PDT). Notably, PDT has developed into an important therapeutic tool against several serious diseases, such as

• cancer [39], and bacterial, fungal, parasitic and viral infections [40][41]. In general, PDT operates on the basis of a photosensitizer, which generates reactive intermediates upon irradiation [42][43][44][45]. Hence, in the type-I mechanism the photosensitizer induces the formation of reactive oxygen

• -based nanoparticles [58][59]. But although these classes of compounds have been intensively studied and already contributed significantly to the field of PDT, there is still a demand for novel DNA-photodamaging ligands that could be applied for specific purposes, e.g., to improve efficacy or to limit

CuAAC-inspired synthesis of 1,2,3-triazole-bridged porphyrin conjugates: an overview

• Dileep Kumar Singh

Beilstein J. Org. Chem. 2023, 19, 349–379, doi:10.3762/bjoc.19.29

• medicinal chemistry. Owing to the strong absorption in the visible region, these 18π-electron systems also demonstrate excellent photoluminescence properties. Therefore, porphyrin hybrids have been widely used as efficient sensitizers for PDT applications and dye-sensitized solar cells (DSSCs). Because the

• 85 and porphyrin-psoralen conjugate 87 could be potential candidates for PDT applications. Recently, Charisiadis et al. [45] explored this modular click chemistry protocol for the synthesis of a noble metal-free meso-triazole cobalt porphyrin diimine-dioxime conjugate 91 by covalently connecting a

• -soluble nanowires, nanorods, and nanospheres. In addition, these triazoloporphyrins have a wide range of medical applications, including photoinduced cytotoxicity against cancer cells, drug delivery, as phototherapeutic agents, and PDT applications. I believe this review will be useful and encourage

Fluorinated maleimide-substituted porphyrins and chlorins: synthesis and characterization

• Valentina A. Ol’shevskaya,
• Elena G. Kononova and
• Andrei V. Zaitsev

Beilstein J. Org. Chem. 2019, 15, 2704–2709, doi:10.3762/bjoc.15.263

• conversions [7]. Porphyrins have been extensively studied as potential photosensitizers in a photodynamic therapy (PDT) [8][9], a promising treatment modality for several cancer and infectious diseases. In PDT, light, O2, and a photosensitizing drug are combined to produce a selective therapeutic effect via

• thus to affect the photophysical, photochemical and tumor-specific properties of the porphyrin system. Such an approach provides a platform to new photosensitizers with optimized characteristics useful for biomedical applications including PDT. Currently a number of investigations directed for the

• widely used to generate singlet oxygen for PDT applications [9][23]. We intend here to combine within one molecule the structural specificity of a meso-fuorinated porphyrin/chlorin macrocycle and maleimide units to develop novel multifunctional compounds with improved properties for various applications

Synthesis of a water-soluble 2,2′-biphen[4]arene and its efficient complexation and sensitive fluorescence enhancement towards palmatine and berberine

• Xiayang Huang,
• Xinghua Zhang,
• Tianxin Qian,
• Junwei Ma,
• Lei Cui and
• Chunju Li

Beilstein J. Org. Chem. 2018, 14, 2236–2241, doi:10.3762/bjoc.14.198

• of isoquinoline alkaloids‘ family, P and B can produce singlet oxygen (1O2) and oxide biological substrates under light, and thereby have applications in photodynamic therapy (PDT) [48][49][50]. However, their low quantum yields limit such applications, which could be potentially improved or restored

Synthesis and application of trifluoroethoxy-substituted phthalocyanines and subphthalocyanines

• Satoru Mori and
• Norio Shibata

Beilstein J. Org. Chem. 2017, 13, 2273–2296, doi:10.3762/bjoc.13.224

• –vis spectrum, do not aggregate in solution. These dyes are expected to be developed into medical imaging probes. Phthalocyanine is expected to be used not only as a biological imaging agent but also in cancer treatment. Photodynamic therapy (PDT) is a laser cancer therapy that introduces organic dyes

• laser only to the target tumor cells. The features of ideal PDT agents include, among others: i) strong absorption in the red wavelength region; ii) non-aggregation property; iii) high biocompatibility; iv) good selectivity to cancer cells; v) high quantum yield of singlet oxygen [96]. Since the PDT

• activity of phthalocyanine is remarkably decreased by aggregation, TFEO-Pc, which has a non-aggregation property, is expected to be a highly active PDT drug. Incidentally, improving drug selectivity for cancer cells is a problem in developing cancer therapeutic drugs. Phthalocyanines have the capacity to

Novel β-cyclodextrin–eosin conjugates

• Gábor Benkovics,
• Damien Afonso,
• András Darcsi,
• Szabolcs Béni,
• Sabrina Conoci,
• Éva Fenyvesi,
• Lajos Szente,
• Milo Malanga and
• Salvatore Sortino

Beilstein J. Org. Chem. 2017, 13, 543–551, doi:10.3762/bjoc.13.52

• successfully utilized in photodynamic therapy (PDT). This minimally invasive therapeutic approach has proven to be very well-suited for cancer and bacterial diseases treatment. The PDT is based on the combination of three main components: visible light, a photosensitizer (PS) and molecular oxygen [4][5]. After

• diffuses in the cellular environment over short distances (few tens of nm) resulting in negligible systemic side effects. For PDT applications CDs have been conjugated with porphyrin [7] and protoporphyrin (5-aminolevulinic acid) [8] in order to enhance the membrane penetration of the PS (or its prodrug

• effects (PDT and chemotherapy) have been developed by Král et al. [10][11]. The results achieved by these groups clearly demonstrated the numerous advantages of the PS–CD coupling. However, despite the number of porphyrinoid PSs conjugated with CDs [12][13][14][15][16][17][18][19][20], literature on

A self-assembled cyclodextrin nanocarrier for photoreactive squaraine

• Ulrike Kauscher and
• Bart Jan Ravoo

Beilstein J. Org. Chem. 2016, 12, 2535–2542, doi:10.3762/bjoc.12.248

• ; squaraine; Introduction Photodynamic therapy (PDT) has become a very attractive alternative to traditional cancer therapies due to its efficiency and selectivity [1][2][3][4]. PDT is based on a photosensitizer (PS), which is delivered to cancerous tissue followed by the irradiation with light of an

• class of compounds known as squaraines [13][14][15][16][17][18]. Squaraines are a promising class of fluorescent dyes for PDT. In the past, squaraines showed a very low intersystem-crossing efficiency, leading to the premature conclusion that these dyes cannot be used in PDT [19]. Santos et al. showed

• promising component of PDT [22][23]. Whether squaraines follow the type I or type II mechanism is discussed controversially in the literature. Santos et al. [19][20], Salice et al. [24] and Rapozzi et al. [25] investigated how benzothiazole-squaraines, which are also pursued in this project, cause

Interactions between 4-thiothymidine and water-soluble cyclodextrins: Evidence for supramolecular structures in aqueous solutions

• Vito Rizzi,
• Sergio Matera,
• Paola Semeraro,
• Paola Fini and
• Pinalysa Cosma

Beilstein J. Org. Chem. 2016, 12, 549–563, doi:10.3762/bjoc.12.54

• photodynamic therapy (PDT) applications [19]. Some authors of this paper have extensively studied the behavior of several PSs in the presence of CDs [19][20] highlighting the important role of the latter. Interestingly, among PSs the use of thiobases has emerged as a novel approach for PDT applications in

• several clinical diseases [12][21]. One of the most commonly used thiobase for PDT applications is S4TdR, whose triplet state is generated upon photoexcitation with a quantum yield of one [22][23][24][25][26]. Under these conditions the production of reactive oxygen species (ROS), well-known toxic agents

• -CD, 2-HP-β-CD, 2-HP-γ-CD, DIMEB and TRIMEB. This is a preliminary work in order to (i) study, in the next future, its photochemical behavior in the presence of CDs, and to (ii) preserve it from oxidative degradation when irradiated during PDT treatments. In this work, absorption spectroscopic

A versatile δ-aminolevulinic acid (ΑLA)-cyclodextrin bimodal conjugate-prodrug for PDT applications with the help of intracellular chemistry

• Chrysie Aggelidou,
• Theodossis A. Theodossiou,
• Antonio Ricardo Gonçalves,
• Mariza Lampropoulou and
• Konstantina Yannakopoulou

Beilstein J. Org. Chem. 2014, 10, 2414–2420, doi:10.3762/bjoc.10.251

• , molecular/drug carrier with the capacity to undergo intracellular transformation into protoporphyrin IX (PpIX), an endogenous powerful photosensitizer for photodynamic therapy (PDT). The water-soluble derivative 2 was prepared by esterifying δ-azidolevulinic acid with heptakis(6-hydroxyethylamino-6-deoxy)-β

• in terms of water solubility and lack of aggregation. Keywords: cyclodextrins; PDT; protoporphyrin IX; prodrug; δ-aminolevulinic acid; Introduction Porphyrins have long been used as agents for tumor photodiagnosis (PDD) and photodynamic therapy (PDT) because of their preferential accumulation in

• very efficient for PDT [3]. Compound 1 and its more lipophilic esters, methyl and hexyl levulinate, have been approved for clinical use as PpIX precursors against several cancers such as basal cell carcinoma, bladder cancer, actinic keratosis, etc. [4]. Compound 1 is a polar, zwitterionic compound

From porphyrin benzylphosphoramidate conjugates to the catalytic hydrogenation of 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin

• Marcos C. de Souza,
• Leandro F. Pedrosa,
• Géssica S. Cazagrande,
• Vitor F. Ferreira,
• Maria G. P. M. S. Neves and
• José A. S. Cavaleiro

Beilstein J. Org. Chem. 2014, 10, 628–633, doi:10.3762/bjoc.10.54

• hydrogenation; chlorin; isobacteriochlorin; phosphoramidate; porphyrin; Introduction The use of porphyrin derivatives as photosensitizers is considered for the photodynamic therapy (PDT) of malignant tumors and the treatment of age-related macular degeneration in several countries [1][2]. It is already known

• reduction of the macrocycle, thereby affording chlorin and other derivatives (Scheme 1). Considering the importance of TPPF20 as a template for further functionalizations [7] and the better suitability of chlorins for PDT compared to porphyrins due to their enhanced red-shifted Q bands [2], we decided to

Synthesis of meso-substituted dihydro-1,3-oxazinoporphyrins

• Satyasheel Sharma and
• Mahendra Nath

Beilstein J. Org. Chem. 2013, 9, 496–502, doi:10.3762/bjoc.9.53

• derivatives has emerged as one of the major areas of research due to the success of these molecules for the eradication of malignant cells by photodynamic therapy (PDT) after their selective accumulation [7][8][9][10] in neoplastic tissues. In addition, the low dark-toxicity profile, easy removal from the

• [25], pyrrolidinone [26], pyrrolidine [27] and piperazine [28], to the porphyrin periphery. In addition, many porphyrin dimers and trimers have displayed significant biological efficacy [29] and some of these are used as photosensitizers in PDT applications for the treatment of various types of