Iron(III) Complexes of Vitamin B6 Schiff Base with Boron‐Dipyrromethene Pendants for Lysosome‐Selective Photocytotoxicity. Issue 13 (6th April 2018)

• Record Type: Journal Article
• Authors: Sahoo, Somarupa; Podder, Santosh; Garai, Aditya; Majumdar, Shamik; Mukherjee, Nandini; Basu, Uttara; Nandi, Dipankar; Chakravarty, Akhil R.
• Is Part Of: European journal of inorganic chemistry. Issue 13(2018)
• Page Start: 1522
• Page End: 1532
• Publication Date: 2018-04-06
• Subjects: Bioinorganic chemistry -- Iron -- Antitumor agents -- Photochemistry -- Vitamin B6; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.201701487
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract : Iron(III) complexes of a vitamin B6 Schiff base and NNN ‐donor ligands with pendant boron‐dipyrromethene (BODIPY) moieties; namely, [Fe(L 1–3 )(L 4, 5 )](NO3 ) (1 –4 ), where L 1 is benzyl‐bis[(pyridin‐2‐yl)methyl]methanamine (bzdpa in1 ), L 2 is a noniodinated BODIPY‐appended dipicolylamine ligand (in2, 3 ), L 3 is the diiodinated BODIPY analogue in4, L 4 is a vitamin B6 Schiff base, namely 3‐hydroxy‐5(hydroxymethyl)‐4‐{[(2‐hydroxyphenyl)imino]methyl}‐2‐methylpyridine (in1, 3, and4 ), and L 5 is 2‐[(2‐hydroxyphenylimino)‐methyl]phenol (in2 ) as a nonpyridoxal Schiff base, were prepared, characterized, and their cellular localization and cytotoxic activity in light and in the dark were studied. The diiodo–BODIPY complex4 displays remarkable photoinduced cytotoxicity in visible light (400–700 nm), with IC50 values within 0.11–0.25 µm and about 200‐fold lower dark toxicity. Complex3, being fluorescent, was used for cellular imaging by confocal microscopy. Complex4 shows supercoiled pUC19 DNA cleavage activity through the generation of singlet oxygen ( 1 O2 ) as the reactive oxygen species (ROS). Selective uptake of the complexes is observed from competitive cellular incorporation assays in cancer and noncancer cells. The complexes also show no apparent toxicity up to 100 µm in the immortal human lung epithelial cells HPL1D in both light and the dark. Complex3 shows preferential accumulation in lysosomes, giving a Pearson's correlation coefficient value of about 0.7. Abstract : Ternary iron(III) complexes of NNN ‐donor ligands having pendant BODIPY moieties and an O, N, O ‐donor vitamin B6 Schiff base show singlet‐oxygen‐induced photocytotoxicity in cancer cells, with apoptotic cell death and lysosomal localization from imaging studies. The complexes display higher cellular uptake in cancer cells than in non‐cancerous cells.