3119-93-5Relevant academic research and scientific papers
Aminosquaraines as potential photodynamic agents: Synthesis and evaluation of in vitro cytotoxicity
Magalh?es,Gra?a, Vania C.,Calhelha, Ricardo C.,Ferreira, Isabel C.F.R.,Santos, Paulo F.
, p. 4467 - 4470 (2017)
The synthesis of several aminosquaraine cationic dyes displaying strong absorption within the so-called phototherapeutic window (650–850 nm) is described. Their cytotoxicity, under dark and illuminated conditions, was tested against several human tumor cell lines (breast, lung, cervical and hepatocellular carcinomas) and non-tumor porcine liver primary cells. All compounds showed to inhibit the growth of the tumor cells upon irradiation more than in the absence of light, in more or less extension, clearly exhibiting photodynamic activity. The photosensitizing ability against some cell lines, together with the low toxicity for the non-tumor primary PLP2 cells displayed by some of the compounds synthetized, turns them into potential candidates as photosensitizers for PDT.
A self-immolative near-infrared probe based on hemi-benzothiazolecyanine for visualizing hydrogen peroxide in living cells and mice
Gong, Yi?Jun,Feng, Dan?Dan,Liu, Wei?Ning,Fang, Jing?Kun,Feng, Suling
, (2021)
Hemicyanine dyes including hemi-indocyanine and hemi-benzindocyanine have been attracted considerable attentions to develop near infrared probes for in vivo fluorescence imaging. However, hemi-benzothiazolecyanine dye (MTR) is rarely reported for detection analytes. In this work, to extend the sensing applications of MTR, we present an optimized route for facile preparation of the dye. And as a proof-of-concept, a self-immolative NIR probe MTR-HH based on hemi-benzothiazolecyanine dye was designed and synthesized for H2O2. The probe exhibited a 284-fold fluorescent enhancement to H2O2 with a detection limit of 0.32 μM over other biospecies. Moreover, MTR-HH was successfully applied for visualizing endogenous H2O2 in living cells and mice.
Host-guest assembly of squaraine dye in cucurbit[8]uril: Its implication in fluorescent probe for mercury ions
Xu, Yongqian,Panzner, Matthew J.,Li, Xiaopeng,Youngs, Wiley J.,Pang, Yi
, p. 4073 - 4075 (2010)
The binding interactions between SQ2 squaraine dye and cucurbit[8]uril (CB8) effectively removes the aggregation of SQ2 in aqueous solution by forming a 1:1 inclusion complex. The resulting SQ2·CB8 complex exhibits highly selective fluorescence quenching by Hg2+ ions, as a result of the synergetic binding between CB8, SQ2 and metal cation.
Molecular assembly of a squaraine dye with cationic surfactant and nucleotides: Its impact on aggregation and fluorescence response
Xu, Yongqian,Malkovskiy, Andrey,Wang, Qiuming,Pang, Yi
, p. 2878 - 2884 (2011)
A novel fluorescent system has been assembled by using ATP, surfactant, and a squaraine dye in an aqueous buffer solution. In the system, a cationic surfactant such as cetyl trimethyl ammonium bromide (CTAB) forms a sphere-like micelle, whose positive charge at the surface of the micelle attracts the negatively charged ATP to form a unique organized nanostructure. Such an organized system is shown to interact with the squaraine dye (SQ) to perturb its aggregate structure, thereby generating the optical response. The nanostructure of the assembly has been characterized by dynamic light-scattering (DLS) and atomic force microscopy (AFM). The unique feature of the developed sensing system is that the analytes ATP form part of the assembly structure. The system utilizes forces such as electrostatic interaction and π-π stacking of the aromatic segment of ATP and SQ to achieve the selective detection of ATP.
Ability of carbazole salts, inhibitors of Alzheimer β-amyloid fibril formation, to cross cellular membranes
Saengkhae, Chantarawan,Salerno, Milena,Ades, Dominique,Siove, Alain,Le Moyec, Laurence,Migonney, Veronique,Garnier-Suillerot, Arlette
, p. 124 - 131 (2007)
Alzheimer's disease is characterized by the presence of β-amyloid fibril formation. The inhibition of this peptide accumulation may be a prevention method for Alzheimer's disease. Several classes of molecules have been reported to inhibit β-amyloid fibril formation and among them carbazoles. However, very few studies have been performed to determine the destination of such molecules in vivo and especially if they can pass the blood brain barrier. The aim of this paper is to study whether carbazoles could pass the blood brain barrier, i.e. if they can circumvent ATP Binding Cassette (ABC) transporters such as P-glycoprotein (P-gp) and Multidrug Resistance-associated protein (MRP1) which efficiently limit drug brain uptake. For this purpose we have synthesized a fluorescent derivative of carbazole benzothiazolium iodide 1,2 disubstituted ethylene (referred as carbazole thiazole: CT), which can be easily detected and followed in the pre-trial study phases in cells or in tissue. We use cellular models overexpressing P-gp and MRP1. Our results show that: i) CT is able to cross membranes and to penetrate rapidly inside the cells, ii) CT is a P-gp substrate and consequently its accumulation in P-gp overexpressing cells is very low, iii) CT is a poor MRP1 substrate. In addition once inside the cells, CT rapidly binds to DNA and is then slowly reduced by intracellular reducing agents. In conclusion, the efficiency of carbazole derivatives in inhibiting the β-amyloid formation in vivo could be highly compromised because, as P-gp substrates, they will probably not cross the blood brain barrier.
Synthesis of pH-sensitive benzothiazole cyanine dye derivatives containing a pyridine moiety at the meso position
Lovett, Wheeler R.,Al Hamd, Alaa,Casa, Stefanie,Henary, Maged
, (2021)
Four benzothiazole-derived pentamethine cyanine dyes were synthesized with a pyridine moiety at the meso-position of the methine chain with a reaction yield of 89–93%. These dyes were prepared with high purity in a three-step synthesis as prospective pH-responsive probes. Each compound absorbed and fluoresced between 630 and 670 nm within the far-red range of the visible spectrum with high molar absorptivity values calculated between 134,910 L mol ?1 cm?1 and 163,816 L mol ?1 cm?1 and quantum yields between 9% and 17%. When a 20 μM solution of dye derivatives are exposed to hydrochloric acid in the range of pH 5–6 in ethanol, all the dyes experienced a blueshift in absorbance and emission as well as a decrease in spectral intensity that enables them to operate as pH probes. These properties were further validated via computational studies showing pyridine's influence on each molecules' spectral properties, and pathways for electron delocalization in the presence and absence of acid were proposed.
An NIR fluorescent probe of uric HSA for renal diseases warning
Li, Haidong,Yao, Qichao,Fan, Jiangli,Du, Jianjun,Wang, Jingyun,Peng, Xiaojun
, p. 79 - 85 (2016)
Diseases of the kidney, including acute kidney injury, nephritic syndromes, chronic kidney disease, and renal cysts, are accompanied by a series of characteristic clinical features. Human Serum Albumin (HSA) is regarded as an important biomarker for early warning of kidney diseases among them. To the best of our knowledge, although some fluorescent probes of HSA had reported in blood plasma under high concentrations of HSA, most of them could not reach the detection sensitivity of low concentrations of HSA in urine. In this work, an NIR fluorescent probe NIR-HSA for HSA based on TICT mechanism is reported, which can used in solution detection with 8.83-fold fluorescence enhancement, rapid response (completed within 5 s), excellent sensitivity (DL 26.16 nM), and excellent stability. In human urine detection, NIR-HSA clearly demonstrated perfect recovery property, and good potential to be applied to detect trace HSA for warning of critical diseases.
A new Vilsmeier-type reaction for one-pot synthesis of pH sensitive fluorescent cyanine dyes
El-Shishtawy, Reda M.,Almeida, Paulo
, p. 7793 - 7798 (2006)
A new Vilsmeier-type reaction is suggested for the synthesis of novel indocarbocyanine pH sensors, which are fluorescent when protonated but nonfluorescent upon proton abstraction. These sensors show significant ratiometric UV-visible as well as fluorescence spectral changes upon subtle variation of pHs with pKa values near neutral.
Highly selective turn-on red fluorescence probes for visualization of the G-quadruplexes DNA in living cells
Kang, Yongqiang,Wei, Chunying
, (2021/10/27)
Studies on small molecule fluorescent probes for detecting G-quadruplexes DNA have bring about an extensive attention in recent years. In this paper, we designed and synthesized three benzothiazole derivatives named 2a-2c under moderate reaction conditions and investigated their interactions with DNA (single-stranded, duplex, i-motif and G-quadruplex) and distribution in living cell. Three compounds present a large Stokes shift (～90 nm) and a weak red fluorescence emission, and they exhibit a good selectivity and sensitive turn-on fluorescence response for the promoter G-quadruplex DNA (bcl-2, c-myc and c-kit 2) and mitochondria G-quadruplex (KSS). The affinity of 2a and 2b with N-alkyl side chain group to DNA is stronger than that of 2c with an anion group, therefore, they also increase the stability of the G-quadruplex structure. 2b induces the conformational change of both bcl-2 and KSS G-quadruplexes, while all compounds induce the folding of bcl-2 from the coiled structure to the hybrid G-qrudruplex. Three compounds interact with the G-quadruplex DNA mainly by end-stacking mode. Furthermore, MTT assays and confocal fluorescence images show that these compounds can enter the living HepG2 cells with low cytotoxicity. 2a-2c are mainly located in the mitochondrion and interacted with mitochondria G-quadruplex DNA, while only weak fluorescence can be found in cell nucleus. In a word, 2a-2c can be implied in image of G-quadruplex DNA in living cells.
A photosensitizer with conformational restriction for enhanced photodynamic therapy
Du, Jianjun,Fan, Jiangli,Huang, Daipeng,Huang, Haiqiao,Long, Saran,Peng, Xiaojun
supporting information, p. 9100 - 9103 (2021/09/14)
A rigid hemicyanineCSZ-Jand a flexible moleculeESZ-Jwere synthesized. In particular, the conformationally restrainedCSZ-Jhad higher fluorescence quantum yields, longer fluorescence lifetimes and higher triplet state quantum yields.CSZ-Jcould generate highly cytotoxic ROS simultaneouslyviatype I and type II processes. This will contribute to the design and development of new photosensitizers in the future.
