2941-63-1Relevant academic research and scientific papers
Recyclable copper-catalyzed cyclization of o-haloanilides and metal sulfides: An efficient and practical access to substituted benzothiazoles
Cai, Mingzhong,Hao, Wenyan,Huang, Wencheng,Ye, Qian
, (2022/01/19)
An efficient heterogeneous copper-catalyzed cyclization of o-haloanilides and metal sulfides has been achieved via the C–S coupling in DMF at 80 or 140 °C in the existence of an MCM-41-bound NHC-Cu(I) catalyst and then intramolecular condensation, delivering a wide range of substituted benzothiazoles in mostly good to high yields. This new MCM-41-NHC-CuI complex can facilely be obtained by a two-step procedure starting from easily accessible and inexpensive reagents and reused more than seven times without any significant loss of its catalytic efficiency. The present protocol has been successfully applied to the gram-scale synthesis of two antitumor agents 5F203 and PMX 610.
Benzothiazole-Schiff base-Tr*ger's base derivative and preparation method and application thereof
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Paragraph 0047; 0056-0057; 0062-0063, (2020/08/02)
The structural general formula of a benzothiazole-Schiff base-base derivative is shown as one of the following formulas, and the preparation method of the benzothiazole-Schiff base-base derivative comprises the following steps: selecting p-bromoaniline, paraformaldehyde, n-butyllithium, p-aminobenzoic acid, substituted o-phenylenediamine, benzothiazole and the like as raw materials, and performingmulti-step reaction to obtain the benzothiazole-Schiff base-base derivative. The product emits yellow green light, the Stokes shift is large, the product has obvious aggregation-induced emission, theexcellent solid-state luminescence performance and good thermal stability, and antifungal performance tests prove that part of the compounds have a good antibacterial effect.
STYRYLBENZOTHIAZOLE DERIVATIVES AND USES IN IMAGING
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Page/Page column 6; 52, (2019/12/04)
This disclosure relates to styrylbenzothiazole derivatives for use as in vivo imaging agents for the diagnosis of Parkinson's disease (PD) or other degenerative disorders or conditions of the central nervous system. Early diagnosis is particularly advantageous as neuroprotective treatment can be applied to healthy neural cells to delay or even prevent the onset of debilitating clinical symptoms.
Benzothiazole derivative NTNO and preparation method and application thereof
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Paragraph 0024-0027, (2019/03/08)
The invention discloses a benzothiazole derivative NTNO, and a preparation method and application thereof. The derivative is specifically 6-(2-(6-nitrobenzothiazole-2-yl)-vinyl)naphthalen-2-ol (NTNO).The preparation method comprises the steps of dissolving 6-hydroxyl-2-naphthaldehyde and 2-methyl-6-nitrobenzothiazole in a small amount of ethanol, adding piperidine, and heating to allow reaction to obtain a crude product; after a solvent is removed from the crude product, performing silica-gel column separation to obtain a pure product. As a probe, NTNO does not fluoresce under acidic condition. With the rise of pH, new fluorescence emission at 526 nm appears and is gradually intensified. The pKa value is 7.85+/-0.022, the linear response range of the pH is 6.90-8.20, and monitoring of pH(6.8-7.4) change in a neutral cytoplasmic range is facilitated. In addition, the NTNO has the advantages of good OH selectivity, large Stokes shift and the like. Furthermore, the NTNO also has excellent cell membrane permeability and cytoplasmic staining ability and is suitable for the monitoring of pH changes within the cytoplasmic matrix range.
Efficient CDI/CH3SO3H-catalyzed, microwave-assisted synthesis of 2-substituted benzothiazoles
Li, Yao-Wei,Zhang, Pei-Ming,Li, Rui,Bai, Yan,Yu, Yu,Gan, Zong-Jie
supporting information, p. 34 - 39 (2019/05/04)
CDI combined with CH3SO3H was found to be highly effective for the cyclization of 2-aminothiophenol derivatives with carboxylic acids under MW condition. Fourteen benzothiazole derivatives were synthesized in good yield and their structures were characterized by1H-NMR,13C-NMR, IR and mass spectrometry. This simple, rapid synthetic method is believed to provide a useful process for the synthesis of 2-substituted benzothiazole compounds.
Eco-friendly syntheses of 2-substituted benzoxazoles and 2-substituted benzothiazoles from 2-aminophenols, 2-aminothiophenols and DMF derivatives in the presence of imidazolium chloride
Tian, Qingqiang,Luo, Wen,Gan, Zongjie,Li, Dan,Dai, Zeshu,Wang, Huajun,Wang, Xuetong,Yuan, Jianyong
supporting information, (2019/01/21)
A simple, economical and metal-free approach to the synthesis of 2-substituted benzoxazoles and 2-substituted benzothiazoles from 2-aminophenols, 2-aminothiophenols and DMF derivatives, only using imidazolium chloride (50% mmol) as promoter without any other additive, was reported. Various 2-substituted benzoxazoles and 2-substituted benzothiazoles were thus prepared in moderate to excellent yields.
Synthesis method of 2-substituted benzoxazole, 2-substituted benzothiazole and derivatives thereof
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Paragraph 0047; 0052-0053, (2019/02/10)
The invention provides a synthesis method of 2-substituted benzoxazole, 2-substituted benzothiazole and derivatives thereof. In the method, through ortho-aminophenol/2-aminothiophenol cyclization catalyzed by imidazole hydrochloride, synthesis of functionalized 2-substituted benzoxazole and 2-substituted benzothiazole is realized; the method is simple, economical and high in practicality. No othercatalysts or additives are used, the synthesis method ensures good functional group tolerance and excellent yield and purity, the reaction time is short, no harsh reaction conditions are needed, andthe method is suitable for industrial production.
Design, synthesis and photophysical studies of styryl-based push-pull fluorophores with remarkable solvatofluorochromism
Safir Filho, Mauro,Fiorucci, Sebastien,Martin, Anthony R.,Benhida, Rachid
, p. 13760 - 13772 (2017/11/27)
A library of 20 styryl-based push-pull dyes derived from 6-amino substituted benzothiazoles were prepared by an efficient and practical synthetic route from low-cost starting materials. The dyes were firstly designed to present an effective anchoring site for subsequent conjugation. A series of aryl scaffolds, from substituted phenyl rings containing electron donating and withdrawing groups to polycyclic aromatic derivatives, were screened. The inductive effect of N-alkyl substituted benzothiazoles was also explored for three different arrangements. The investigation of the structure-photophysics relationship was performed by UV-vis absorption and steady-state fluorescence emission measurements in solution and by TD-DFT calculations. The dyes presented high brightness, absorption bands in the visible range (～370-453 nm) and large solvatofluorochromism comprising all the visible spectrum, as a consequence of the strong intramolecular charge transfer (ICT) nature of their excited state.
Synthesis and characterization of near-infrared absorbing water soluble squaraines and study of their photodynamic effects in DLA live cells
Shafeekh, Kulathinte M.,Soumya, Mohanannair S.,Rahim, Moochikkadavath A.,Abraham, Annie,Das, Suresh
, p. 585 - 595 (2014/05/20)
Here, we report the synthesis, photophysical properties and photodynamic effects in DLA live cells of three water soluble squaraine dyes, viz. bisbenzothiazolium squaraine dyes SQMI and SQDI with iodine in one and both benzothiazolium units, respectively, and an unsymmetrical squaraine dye ASQI containing iodinated benzothiazolium and aniline substituents. The diiodinated SQDI showed an anomalous trend in both fluorescence and triplet quantum yields over the monoiodinated SQMI, with SQDI showing higher fluorescence and lower triplet quantum yields compared to SQMI. Nanosecond laser flash photolysis of SQDI and SQMI indicated the formation of triplet excited states with quantum yield of 0.19 and 0.26, respectively. On photoirradiation, both the SQDI and SQMI generate singlet oxygen and it was observed that both dyes undergoing oxidation reactions with the singlet oxygen generated. ASQI which exhibited a lower triplet quantum yield of 0.06 was, however, stable and did not react with the singlet oxygen generated. In vitro cytotoxicity studies of these dyes in DLA live cells were performed using Trypan blue dye exclusion method and it reflect an order of cytotoxicity of SQDI>SQMI>ASQI. Intracellular generation of the ROS was confirmed by dichlorofluorescein assay after the in vitro PDT. Synthesis, photophysical properties and photodynamic effects in DLA live cells of three water soluble squaraine dyes, SQDI, SQMI and ASQI, are presented. On photoirradiation, both the SQDI and SQMI generate singlet oxygen where both the dyes undergoing oxidation reactions with the singlet oxygen generated, whereas ASQI was stable and did not react with the singlet oxygen. In vitro cytotoxicity studies of these dyes in DLA cells were performed using Trypan blue dye exclusion method and intracellular generation of ROS was confirmed using dichlorofluorescein assay after the in vitro PDT.
Synthesis of thiacyanine dyes containing coumarin moieties at benzothiazole rings
Krasnaya, Zhanna A.,Kuz'Min, Vladimir A.,Litvinkova, Lyubov V.,Dorofeeva, Evgeniya O.,Zlotin, Sergei G.
, p. 212 - 214 (2013/09/02)
New bischromophoric dyes (thiacarbocyanine and thiadicarbocyanine) containing coumarin moieties at each of the two benzothiazole systems, as well as monomethinecyanine containing coumarin moiety at only one heterocyclic system, manifest significant batho-chromic shift compared to relative coumarin-free dyes.
