New Route to Glycosylated Porphyrins via Aromatic Nucleophilic Substitution (SNAr)—Synthesis and Cellular Uptake Studies

Glycoporphyrins are group of compounds of high value for the purpose of photodynamic therapy and other biomedical applications. Despite great progress in the field, new diversity-oriented syntheses of carbohydrate-porphyrin hybrids are increasingly desired. Herein, we present efficient, mild, and metal-free conditions for synthesis of glycoporphyrins. The versatile nature of the SNAr procedure is presented in 16 examples. Preliminary biological studies have been conducted on the cytotoxicity and cellular uptake of the final molecules.

Water-Soluble Chlorin/Arylaminoquinazoline Conjugate for Photodynamic and Targeted Therapy

A new water-soluble conjugate, consisting of a chlorin-e₆ photosensitizer part, a 4-arylaminoquinazoline moiety with affinity to epidermal growth factor receptors, and a hydrophilic β-d-maltose fragment, was synthesized starting from methylpheophorbide-a in seven steps. The prepared conjugate exhibited low levels of dark cytotoxicity and pronounced photoinduced cytotoxicity at submicromolar concentrations in vitro, with an IC₅₀(dark)/IC₅₀(light) ratio of ∼368 and a singlet oxygen quantum yield of about 20%. In tumor-bearing Balb/c nude mice, conjugate 1 preferentially accumulates in the tumor tissue. Irradiation of the nude mice bearing A431 xenograft tumors after intravenous administration of the prepared conjugate with a relatively low light dose (50 J/cm²) produced an excellent therapeutic effect with profound tumor regression and low systemic toxicity.

Synthesis of Porphyrin and Bacteriochlorin Glycoconjugates through CuAAC Reaction Tuning

Rapid and reproducible access to a series of unique porphyrin and bacteriochlorin glycoconjugates, including meso-glycosylated porphyrins and bacteriochlorins, and beta-glycosylated porphyrins, via copper catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC) is reported for the first time. The work presented highlights the system-dependent reaction conditions required for glycosylation to porphyrins and bacteriochlorins based on the unique electronic properties of each ring system. Attenuated reaction conditions were used to synthesize fifteen new glycosylated porphyrin and bacteriochlorin analogs in 74 - 99% yield, and were extended to solid support to produce the first oligo(amidoamine)-based porphyrin glycoconjugate. These compounds hold significant potential as next generation water soluble catalysts and photodynamic therapy/photodynamic inactivation (PDT/PDI) agents.

Trends and targets in antiviral phototherapy

Photodynamic therapy (PDT) is a well-established treatment option in the treatment of certain cancerous and pre-cancerous lesions. Though best-known for its application in tumor therapy, historically the photodynamic effect was first demonstrated against bacteria at the beginning of the 20^th century. Today, in light of spreading antibiotic resistance and the rise of new infections, this photodynamic inactivation (PDI) of microbes, such as bacteria, fungi, and viruses, is gaining considerable attention. This review focuses on the PDI of viruses as an alternative treatment in antiviral therapy, but also as a means of viral decontamination, covering mainly the literature of the last decade. The PDI of viruses shares the general action mechanism of photodynamic applications: the irradiation of a dye with light and the subsequent generation of reactive oxygen species (ROS) which are the effective phototoxic agents damaging virus targets by reacting with viral nucleic acids, lipids and proteins. Interestingly, a light-independent antiviral activity has also been found for some of these dyes. This review covers the compound classes employed in the PDI of viruses and their various areas of use. In the medical area, currently two fields stand out in which the PDI of viruses has found broader application: the purification of blood products and the treatment of human papilloma virus manifestations. However, the PDI of viruses has also found interest in such diverse areas as water and surface decontamination, and biosafety.

A glycoporphyrin story: from chemistry to PDT treatment of cancer mouse models

Glycoporphyrin: from bench to preclinical studies on PDX xenografted on mice.

Synthesis of a novel CB2 cannabinoid-porphyrin conjugate based on an antitumor chromenopyrazoledione

With the objective of developing an antitumor agent, the synthesis of a chromenopyrazoledione conjugated to a tetraphenylporphyrin is described. A complete conformational analysis of the novel porphyrin conjugate was performed using ab initio Hartree–Fock calculations at the 6-31G* level. The novel conjugate (14) shows stronger absorption intensity for both Soret and Q-bands than the free meso-tetraphenylporphyrin. It binds weakly but selectively to the cannabinoid receptor type-2. During the synthetic approach, a new tetraphenylporphyrin, 5-[4-(3,5-dioxomorpholino)phenyl]-10,15,20-triphenylporphyrin (10), has been characterized.