Semi-synthesis and PDT activities of a new amphiphilic chlorin derivative

Phototoxicity in a laryngeal cancer cell line enhanced by a targeting amphiphilic chlorin photosensitizer

“…However, after 16 h of incubation, CHL-T was only about two times more cytotoxic than HY [22]. Previous studies in our group showed the same in other cell line and support that the period of 2 h is enough to chlorin derivatives to achieve lower IC 50 , while HY needs more time to accumulate and consequently to reducing its IC 50 [17].…”

“…The hypericin (HY) was synthetized by Dr. Anderson O. Ribeiro from Center of Natural Sciences and Humanities of Federal University of ABC (Santo Andre, SP, Brazil) according to described protocols [18] and chlorin derivatives (CHL and CHL-T) were synthetized by Dr. Kleber T. Oliveira [17] from Chemistry Department of Federal University of Sao Carlos (Sao Carlos, SP, Brazil). The stock solutions were prepared in dimethyl sulfoxide (DMSO) at 1000 μg mL −1 , sonicated, sterilized by filtering through a 0.22 μm pore membrane and stored at 4°C with protection from light.…”

“…There is much interest in identifying the molecular mechanisms associated with PDT-induced cell death, as this understanding can enable the use of novel strategies improving the efficiency of PDT [15,16]. In the present study, methylpheophorbide a (CHL) was semi-synthesized from chlorophyll a, and a amphiphilic chlorin derivative (CHL-T) obtained from (CHL) after transamidation reaction with TRISMA ® (2amino-2-(hydroxymethyl)propane-1,3-diol) [17]. That previous paper from our group indicated that this chemical modification activated cell death in cervical tumor cells in low concentrations, whereas a nonneoplasic cell line was affected only at higher concentrations, demonstrating selectivity for neoplasic cells.…”

Recent applications of porphyrins as photocatalysts in organic synthesis: batch and continuous flow approaches

“…However, issues about why an electron-poor porphyrin such as tetrakis(pentafluorophenyl)porphyrin (TPFPP) is more efficient in an oxidative quenching compared to an electron-rich (e.g., TPP) remained to be elucidated. In this regard, our research group has contributed in the last 10 years with new porphyrin/chlorin synthetic methodologies, and applications of these compounds in photomedicine [23,[25][26][27]. Recently we reported a porphyrin-photocatalyzed protocol for the arylation of enol acetates and elucidated the mechanism explaining why the electron-deficient porphyrin TPFPP is more efficient than TPP in the whole process (Scheme 4A).…”

Targeting Photochemical Scalpels or Lancets in the Photodynamic Therapy Field—The Photochemist's Role

“…To this end, one strategy uses molecular recognition by cell markers such as receptor or antigen over‐expressed on tumor surfaces. Tuning the substituent or conjugation with carbohydrates, amino acids, peptides or PEGs has led to improved localization in the target tissue . Because the folate surface receptor is over‐expressed in several cell lines such as brain, nose, lung and colon cancer cells, folic acid has been successfully used as a sensitizer substituent for a targeted PDT .…”