118276-06-5Relevant articles and documents
Solvatochromic behavior of substituted 4-(nitrostyryl)phenolate dyes in pure solvents and in binary solvent mixtures composed of water and alcohols
Stock, Rafaela I.,Sandri, Crislaine,Rezende, Marcos C.,Machado, Vanderlei G.
, p. 327 - 336 (2018)
Several 4-(nitrostyryl)phenolates have been used recently as solvatochromic dyes in the investigation of pure solvents. Changes in their molecular structures allow a comparison of their solvation patterns to be made in different binary solvent mixtures, in an effort to relate structural factors to the preferential solvation (PS) observed in these media. Firstly, the solvatochromism of four of these probes was studied and a reversal in their solvatochromism was verified, which was expected following a comparison with other similar systems previously studied. The solvatochromic behavior of a series of twelve 4-(nitrostyryl)phenolate dyes was then investigated in water-alcohol mixtures. A sigmoid behavior was verified for one of the dyes in ethane-1,2-diol-water mixtures, and the dye was preferentially solvated by water in the alcohol-rich region. For all other mixture compositions a strong synergy was observed, with the PS of the dye molecules occurring through the less polar moiety of the water-alcohol aggregates in the binary mixtures. In addition, synergy was observed for some dyes, with PS occurring through the less polar moiety of the alcohol-water aggregates. For all of the other water-alcohol mixtures, the probes were preferentially solvated by the alcohol cosolvent. In order to quantify these deviations, a PS (or non-ideality) index PSI was proposed. The PSI values obtained correlated well with the hydrogen-bond donating ability of the alcoholic co-solvent, and also with the basicity of the phenolate dyes, and the trends observed were confirmed with data from the literature for two other phenolate dyes.
A Multicolor Large Stokes Shift Fluorogen-Activating RNA Aptamer with Cationic Chromophores
Steinmetzger, Christian,Palanisamy, Navaneethan,Gore, Kiran R.,H?bartner, Claudia
, p. 1931 - 1935 (2019)
Large Stokes shift (LSS) fluorescent proteins (FPs) exploit excited state proton transfer pathways to enable fluorescence emission from the phenolate intermediate of their internal 4-hydroxybenzylidene imidazolone (HBI) chromophore. An RNA aptamer named Chili mimics LSS FPs by inducing highly Stokes-shifted emission from several new green and red HBI analogues that are non-fluorescent when free in solution. The ligands are bound by the RNA in their protonated phenol form and feature a cationic aromatic side chain for increased RNA affinity and reduced magnesium dependence. In combination with oxidative functionalization at the C2 position of the imidazolone, this strategy yielded DMHBO+, which binds to the Chili aptamer with a low-nanomolar KD. Because of its highly red-shifted fluorescence emission at 592 nm, the Chili–DMHBO+ complex is an ideal fluorescence donor for F?rster resonance energy transfer (FRET) to the rhodamine dye Atto 590 and will therefore find applications in FRET-based analytical RNA systems.
Development of Near-Infrared Nucleic Acid Mimics of Fluorescent Proteins for in Vivo Imaging of Viral RNA with Turn-On Fluorescence
Zhang, Jiaheng,Li, Huiyi,Lin, Bin,Luo, Xingyu,Yin, Peng,Yi, Ting,Xue, Binbin,Zhang, Xiao-Lian,Zhu, Haizhen,Nie, Zhou
supporting information, p. 19317 - 19329 (2021/11/26)
GFP-like fluorescent proteins and their molecular mimics have revolutionized bioimaging research, but their emissions are largely limited in the visible to far-red region, hampering the in vivo applications in intact animals. Herein, we structurally modulate GFP-like chromophores using a donor-acceptor-acceptor (D-A-A′) molecular configuration to discover a set of novel fluorogenic derivatives with infrared-shifted spectra. These chromophores can be fluorescently elicited by their specific interaction with G-quadruplex (G4), a unique noncanonical nucleic acid secondary structure, via inhibition of the chromophores' twisted-intramolecular charge transfer. This feature allows us to create, for the first time, FP mimics with tunable emission in the near-infrared (NIR) region (Emmax = 664-705 nm), namely, infrared G-quadruplex mimics of FPs (igMFP). Compared with their FP counterparts, igMFPs exhibit remarkably higher quantum yields, larger Stokes shift, and better photostability. In a proof-of-concept application using pathogen-related G4s as the target, we exploited igMFPs to directly visualize native hepatitis C virus (HCV) RNA genome in living cells via their in situ formation by the chromophore-bound viral G4 structure in the HCV core gene. Furthermore, igMFPs are capable of high contrast HCV RNA imaging in living mice bearing a HCV RNA-presenting mini-organ, providing the first application of FP mimics in whole-animal imaging.
