Novel styryldehydropyridocolinium derivative as turn-on fluorescent probe for DNA detection

Reversible photoswitching of the DNA-binding properties of styrylquinolizinium derivatives through photochromic [2 + 2] cycloaddition and cycloreversion

“…In contrast, the very low emission intensity of 3d did not change upon the addition of ct DNA. The fluorescence light-up effects of the ligands 3a-c upon association with DNA resembled the ones observed for other styryl-substituted quinolizinium derivatives [62][63][64][65][66][67]. Accordingly, the emission enhancement most likely resulted from the accommodation of the ligand in the constrained binding site of the DNA, which led to a restricted conformational flexibility.…”

“…As the quinolizinium ion has been established as a versatile platform for the development of DNA intercalators [60], we identified styryl-substituted quinolizinium derivatives as a promising basis for the search for photoswitchable DNA binders based on the photocycloaddition-photocycloreversion equilibrium. In fact, some selected styrylquinolizinium derivatives have already been shown to bind to DNA [61][62][63][64][65][66][67], however, their photocycloaddition reaction and the propensity of the corresponding photodimers to release the DNA-binding ligand have not been reported so far. Herein, we report on the photochemical and DNA-binding properties of the selected styrylquinolizinium derivatives 3a-d and demonstrate their ability to operate as photoswitchable DNA ligands.…”

Spectra, Stability and Labeling of a Novel Carbazole Derivative as a Fluorescent Turn-on DNA Probe

“…Some investigators believe that the positively charged heterocycles play an important role in the enhancement of the fluorescent intensity [11][12][13]. Thus, lots of positively charged dyes, such as benzooxazolinium, benzothiazolinium and quinolizinium derivatives have been successfully developed as fluorescent probes for DNA detection [14].…”

A Novel Styryldehydropyridocolinium Homodimer: Synthesis and Fluorescence Properties Upon Interaction with DNA

“…More recently, we found that the styryldehydropyridocolinium derivative D is a fluorescence turn-on probe for DNA. The fluorescence intensity of D increases by a factor of 60-fold upon intercalative binding with DNA [26]. On the other hand, the intercalates DNA@SPC formed by the intercalation of the cationic styryldehydropyridocolinium dye E in DNA base pairs turned out to be high Ag + -selective fluorescence turn on chemosensors [27].…”

“…As a continuous project for the development of DNA probes [26][27][28][29], we report herein, the molecular design of a novel positively charged homodimer of styryldehydropyridocolinium dye (TPTP) and its optical properties upon interaction with DNA (Scheme 2). The choice of styryldehydropyridocolinium derivative as fluorophore was based on the following considerations: a) the positively charged, planar, polycyclic nature of the dye is not only favorable for binding to nucleic acids, but also beneficial for the intercalation process as demonstrated with other DNA probes [30][31][32][33][34][35]; b) large Stokes shift (>100 nm) is an innate nature of asymmetric cyanine dyes [36][37][38][39][40][41][42][43][44][45][46][47]; c) high mobility of the electron-donating and electronaccepting moieties of the dye around the etheno bridge usually leads to strong ICT or TICT optical changes before and after interaction with analytes [33][34][35][36][37].…”