95435-93-1Relevant academic research and scientific papers
Curcumin derivatives as photosensitizers in photodynamic therapy: Photophysical properties and: In vitro studies with prostate cancer cells
Kazantzis,Koutsonikoli,Mavroidi,Zachariadis,Alexiou,Pelecanou,Politopoulos,Alexandratou,Sagnou
, p. 193 - 206 (2020)
Photodynamic therapy (PDT) is a minimally invasive approach to treat various forms of cancer, based on the ability of certain non-toxic molecules (photosensitizers) to generate reactive oxygen species (ROS) after excitation by light of a certain wavelength and eventually induce strong phototoxic reactions against malignant cells and other pathogens. Curcumin is one of the most extensively investigated phytochemicals with a wide range of therapeutic properties and has been shown to induce strong photocytotoxic effects in micromolar concentrations against a variety of cancer cell lines. Curcumin (1) is comparatively evaluated with the naturally occurring bisdemethoxy Curcumin (2), which lacks the two methoxy groups, as well as two newly synthesized curcuminoids, the cinnamaldehyde derivative (3) and the dimethylamino one (4), designed to increase the absorption maximum and hence the tissue penetration. The synthetic curcuminoids were successfully synthesized in sufficient amounts and their photophysical properties such as absorption, fluorescence, photobleaching and free radical generation were investigated. Compound 4 exhibited a significant increase in peak absorption (497 nm) and strong fluorescent emission signals were recorded for all curcuminoids. Photobleaching of 4 was comparable to 1 whereas 2 and 3 showed more extended photobleaching but much higher ROS production in very short irradiation times. Compounds 2 and 4 exhibited specific intracellular localization. After dark and light cytotoxicity experiments against LNCaP prostate cancer cell line for all curcuminoids, concentration of 3 μM and irradiance of 6 mW cm-2 were selected for the PDT application which resulted in remarkable results with very short LD50. Curcuminoids 2 and 4 exhibited a significant dose-dependent PDT effect. The biphasic dose-response photodynamic effect observed for 1 and 3 may provide a strategy against prolonged and sustained photosensitivity.
Synthesis and photophysical properties of ditrifluoroacetoxyboron complexes with curcumin analogues
Cai, Lian,Du, Hengyi,Lyu, Heng,Wang, Dan,Wang, Dunjia
, (2020/12/21)
A new class of ditrifluoroacetoxyboron complexes were designed and synthesized by chelation reaction of curcumins with boron trifluoroacetate. Their photophysical behaviors were studied in different solvents, powder state and PMMA polymer films. The results indicated that these complexes revealed a green to yellow emission at 486–595 nm in solution or PMMA films and an orange to red emission at 598–710 nm in powder state. Especially, complex 2c displayed the strongest emission intensity, the highest quantum yield in solution and the longest fluorescence lifetime in powder state in these complexes. In addtion, the emission bathochromic shifts of these complexes as a function of the solvent polarity parameter ET(30) were investigated by Lippert–Mataga approximation. It was observed that these complexes exhibited the higher values of the dipole moment difference (Δμ) between the ground and excited states, which implied an intense intramolecular charge transfer characteristics and a noticeable emission solvatochromic effect.
Synthesis, photophysical and solvatochromic properties of diacetoxyboron complexes with curcumin derivatives
Lyu, Heng,Wang, Dan,Cai, Lian,Wang, Dun-Jia,Li, Xiao-Ming
, (2019/06/03)
Five novel diacetoxyboron complexes of β-diketones incorporated curcumin moiety were designed and synthesized. Their photophysical behaviors were investigated by UV–vis absorption and fluorescence spectroscopy in different solvents and solid state. It was observed that their fluorescence spectra yielded a blue to yellow-green emission in solution and emitted a yellow to red emission in solid state. Especially, the complex 3b displayed the strongest emission and the highest quantum efficiency (Φu = 0.98) in toluene among these complexes. The CIE coordinate of the complex 3b in solid state was positioned in an ideal red region of the chromaticity diagram. The maximal emission of these complexes exhibited a large wavelength shift and Stokes shift increased with the increase of the solvent polarity. Their dipole moment differences between the ground and excited states were also estimated by using the Lippert–Mataga equation. Meanwhile, their HOMO, LUMO energy levels and energy band gaps were calculated by cyclic voltammetry.
