Benz[e]indole-bearing aminosquaraine dyes: Which of the amines introduced into the squaric ring will be able to induce the best in vitro photodynamic effect?

Photodynamic Therapy: From the Basics to the Current Progress of N-Heterocyclic-Bearing Dyes as Effective Photosensitizers

“…Regarding the photodynamic activity of squaraines, our last review focuses on the effect of the various structural modifications carried out on them on their biological activity [ 247 ]. Nonetheless, it should be noted that the main structural changes carried out more recently in these molecules are mostly the replacement of one of the oxygen atoms of the four-membered central ring by amines (for example, ethanolamines, picolylamines, and sulfonamides) [ 268 , 269 , 270 ] and the functionalization of that same ring with barbituric acid derivatives [ 271 ].…”

Divergent Diazo Approach toward Alkyl 5/4-Hydroxy-3H-benzo[e]indole-4/5-carboxylates

“…s, 1H), 7.72 (d, 2H, J = 8.9 Hz), 7.46 (d, 2H, J = 8.9 Hz), 7.17 (dd, 1H, J = 5.2 and 1.2 Hz), 6.97 (dd, 1H, J = 3.5 and 1.2 Hz), 6.86 (d, 2H, J = 8.9 Hz), 6.82 (dd, 1H, J = 5.2 and 3.5 Hz), 6.72 (d, 2H, J = 8.9 Hz), 3.93 (s, 3H), 3.79 (s, 3H), 3.78 (s, 3H); 13 C{ 1 H} NMR (CDCl 3 , 100 MHz) δ 193. 5,6,. A mixture of methyl 2-diazo-3-oxo-3-(2H-azirin-2-yl)propanoate 1g (100 mg, 0.38 mmol), dimedone 8d (65 mg, 0.46 mmol), and Ni(acac) 2 (5 mg, 19 μmol) in acetonitrile (5 mL) was stirred at rt for 12 h. The solvent was evaporated, and the residue was purified by column chromatography on silica gel (light petroleum/ethyl acetate, 3:1 (v/ v)) to give compound 2o to give a pure product in 102 mg (70% yield) as a light yellow solid: mp 155−157 °C (dec., light petroleum/ ethyl acetate); 1 H NMR (CDCl 3 , 400 MHz) δ 11.84 (br.…”

“…1 Meanwhile, the recent focus has been on the application of useful optical properties of benzo [e]indole derivatives for bioimaging, 1i,2 analytical chemistry, 3 photonic devices, 4 and medicine. 5 All this determined the development of methods for the synthesis of various benzo [e]indoles. 6 However, there are a very limited number of approaches to functionalized benzo [e]indoles, in particular to compounds with a carboxyl/alkoxycarbonyl substituent on the internal benzene rings of the 3Hbenzo [e]indole system (Scheme 1, eqs 1 and 2).…”

Exploring mitochondrial targeting: an innovative fluorescent probe reveals Nernstian potential and partitioning combination

“…Therefore, key optimization features for the mitochondrial targeting illustrated in Fig. 1 involved functional optimization by ortho -/ para -substitution to the benz[ e ]indolinium to tune the cationic-hydrophobic balance to stain mitochondria, 16,17 thus modifying its dielectric features, resulting in the development of aggregation properties attributed to the interaction of transition dipoles. 18–20 The optical optimization through umbelliferone incorporation was used to enhance the fluorescence response.…”