Synthesis, photophysical characterisation and photostability studies of NIR probes with aliphatic, aromatic and chlorinated terminals in 5- and 9-amino positions of benzo[ a ]phenoxazines

Abstract

Synthesis, photophysical characterisation and photostability studies of NIR probes with aliphatic, aromatic and chlorinated terminals in 5-and 9-amino positions of benzo[a]phenoxazines

Novel Benzo[A]Phenoxazinium Chlorides Functionalized with Sulfonamide Groups as Nir Fluorescent Probes for Vacuole, Endoplasmic Reticulum and Plasma Membrane Staining

“…In previous publications, we have reported that the behavior of benzo[a]phenoxazinium chlorides depends on the substituents at the 5-and 9-positions of the heterocycle [23,51]. In the present study, we report the synthesis, photophysical, antifungal, and staining characterizations of six new benzo[a]phenoxazinium chlorides, functionalized with sulfonamide groups.…”

New NIR dyes based on quinolizino[1,9-hi]phenoxazin-6-iminium chlorides: synthesis, photophysics and antifungal activity

“…Regarding the basic form, the usual fluorescence quantum yields are in the range 0.01-0.03 [7,43]. It is seen that the expected improvement from juolidine stiffening of 9-amino position is clearly observed as the quantum yield is above 0.1 for almost all compounds reaching 0.31 for 4b.…”

“…The emerging need of fluorescent probes requires design and strategic synthesis of new fluorescent dyes. Nile Blue (NB) and their derivatives are studied and used as markers due to their fluorescent and solvatochromic characteristics [2][3][4][5][6][7][8][9]. In this context, benzophenoxazinium dyes are structurally compact with high molar extinction coefficients and exhibit strong fluorescence in the near-infrared (NIR) region with high photochemical stability, which indicates the efficacy of these dyes as fluorophores for biological applications [10].…”

“…Keeping in mind the importance and in continuation of our research interest towards the synthesis and applications of benzophenoxazinium salts [2][3][4][5][6][7][8]12,17,18,[35][36][37], we herein report a new series of benzo[a]quinolizino [1,9-hi]phenoxazin-14(5H)-iminium and naphtho [2,3-a]quinolizino [1,9-hi]phenoxazin-14(5H)-iminium chlorides obtained by condensation of nitroso derivative of 8hydroxyjulolidine with naphthalen-1-amine derivatives and anthracen-1-amine, respectively. The introduction of the julolidine nucleous into the polycyclic system is expected to result in maxima absorption and emission wavelengths of fluorophores higher than those obtained from similar unbridged anilines [34].…”

Fluorescent probes based on side-chain chlorinated benzo[ a ]phenoxazinium chlorides: Studies of interaction with DNA

“…As these compounds in water have a tendency to form H-aggregates [23,25], the pK a values are ill-defined. Nevertheless "pK a " values were determined in anhydrous ethanol media and are in the range 4-5 [42]. But the presence of trace amount of water promotes the formation of the acidic form so that the color of solutions in "normal" ethanol is blue instead of the reddish tone observed in anhydrous ethanol and the pK a values increase from 5 to 6.5 range [25].…”