25953-06-4Relevant articles and documents
Synthesis and fluorescence properties of side-chain carboxylated 5,9-diaminobenzo[a]phenoxazinium salts
Frade, Vania H. J.,Gon?alves, M. Sameiro T.,Moura, Jo?o C. V. P.
, p. 4949 - 4952 (2005)
The efficient synthesis of a series of novel side-chain carboxylated 5,9-diaminobenzo[a]phenoxazinium salts is described. The ring system was prepared by the reaction of 5-alkylamino-2-nitrosophenol hydrochlorides with the appropriate N-alkylated-naphthylamine. Evaluation of the visible and fluorescence properties of the cationic dyes was carried out in ethanol and water at physiological pH. In both solvents they showed intense visible absorption maxima in the range 500-638 nm (ethanol) and 625-650 (water), and fluoresced strongly, with fluorescence maxima from 612 to 669 nm (ethanol) and from 654 to 685 nm (water). A wide variation in fluorescence quantum yields is observed, ranging from 0.051 to 0.50 and 0.065 to 0.32 in ethanol and water, respectively.
Synthesis and evaluation of new potential benzo[a]phenoxazinium photosensitizers for anticancer photodynamic therapy
Zhang, Juan,De Sousa, Wellington Tavares,Da Silva, Victor Carlos Mello,Rodrigues, Mosar Correa,Morais, José Athayde Vasconcelos,Song, Jia-Li,Cheng, Zhi-Qiang,Longo, Jo?o Paulo Figueiró,Azevedo, Ricardo Bentes,Jiang, Cheng-Shi,Muehlmann, Luís Alexandre,Zhang, Hua
, (2018)
The use of photodynamic therapy (PDT) and development of novel photosensitizers (PSs) for cancer treatment have received more and more attention nowadays. In the present work, five benzo[a]phenoxazinium derivatives have been prepared and evaluated for their in vitro anticancer photodynamic activity for the first time. They are red light absorbers and show low fluorescence quantum yield. Of these compounds, PS4 exhibited a higher quantum yield for reactive oxygen species (ROS) generation. The assays with cells in vitro showed that PS1 and PS4 were not significantly toxic in the dark, but was robustly toxic against the murine breast adenocarcinoma cells 4T1 and normal murine fibroblast cells NIH-3T3 upon photoactivation. More interestingly, PS5 was particularly selective towards 4T1 cancer cells and nearly non-phototoxic to non-cancerous NIH-3T3 cells. The results described in this report suggest that these new benzo[a]phenoxazinium derivatives are potential candidates as PSs for anticancer PDT. Further investigation of benzo[a]phenoxaziniums for anticancer PDT is warranted.
Synthesis and photophysical studies of new benzo[a]phenoxazinium chlorides as potential antifungal agents
Leit?o, M. Inês P.S.,Raju, B. Rama,Naik, Sarala,Coutinho, Paulo J.G.,Sousa, Maria Jo?o,Gon?alves, M. Sameiro T.
, p. 3936 - 3941 (2016)
A set of four new benzo[a]phenoxazinium chlorides possessing ethyl, propyl, decyl and tetradecyl groups at the 9-amino function of the heterocycle along with a propyl group at the 5-amino position was efficiently synthesized. These compounds displayed fluorescence with maximum emission wavelengths of 673 and 685?nm, in anhydrous ethanol and water. All the benzo[a]phenoxazines were evaluated against the yeast Saccharomyces cerevisiae in a broth microdilution assay. It was found that their antifungal activity depended on the variation in the lengths of the aliphatic chains. The highest MIC activity of 1.56?μM was obtained for compound 7 comprising a di-alkylated propyl substituent at 9-amino position and a propyl chain at the 5-amino position of the heterocycle core.
Substituted 9-Diethylaminobenzo[ a]phenoxazin-5-ones (Nile Red Analogues): Synthesis and Photophysical Properties
Hornum, Mick,Mulberg, Mads W.,Szomek, Maria,Reinholdt, Peter,Brewer, Jonathan R.,Wüstner, Daniel,Kongsted, Jacob,Nielsen, Poul
supporting information, p. 1471 - 1488 (2021/01/13)
Nile Red is a benzo[a]phenoxazone dye containing a diethylamino substituent at the 9-position. In recent years, it has become a popular histological stain for cellular membranes and lipid droplets due to its unrivaled fluorescent properties in lipophilic environments. This makes it an attractive lead for chemical decoration to tweak its attributes and optimize it for more specialized microscopy techniques, e.g., fluorescence lifetime imaging or two-photon excited fluorescence microscopy, to which Nile Red has never been optimized. Herein, we present synthesis approaches to a series of monosubstituted Nile Red derivatives (9-diethylbenzo[a]phenoxazin-5-ones) starting from 1-naphthols or 1,3-naphthalenediols. The solvatochromic responsiveness of these fluorophores is reported with focus on how the substituents affect the absorption and emission spectra, luminosity, fluorescence lifetimes, and two-photon absorptivity. Several of the analogues emerge as strong candidates for reporting the polarity of their local environment. Specifically, the one- and two-photon excited fluorescence of Nile Red turns out to be very responsive to substitution, and the spectroscopic features can be finely tuned by judiciously introducing substituents of distinct electronic character at specific positions. This new toolkit of 9-diethylbenzo[a]phenoxazine-5-ones constitutes a step toward the next generation of optical molecular probes for advancing the understanding of lipid structures and cellular processes.
NILE RED DERIVATIVES FOR IMPROVED RATIOMETRIC IMAGING FOR NERVE-SPECIFIC CONTRAST
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Page/Page column 15; 26, (2019/11/12)
Provided herein are novel Nile Red derivatives with varied electron donating and withdrawing groups to try to influence tissue-specific accumulation and generate a truly adipose specific fluorophore of Formula (I).
