20432-35-3Relevant academic research and scientific papers
Computer aided benzothiazole derivatives. Synthesis, structure and biological study of new push-pull conjugated benzothiazolium salts
Buffa,Zahradnik,Foltinova
, p. 331 - 336 (2001)
As the conjugation is assumed to enhance the biological activity of push-pull type benzothiazolium salts, new compounds with extended conjugated bridge between benzothiazolium and phenyl ring were designed and synthesized. The compounds have been tested against the model microorganism Euglena gracilis as well as 6 microorganisms including Gram-positive and Gram-negative bacteria , a yeast and a mould. In accordance with predictions, the prepared compounds showed enhanced activity against Euglena and Gram-positive bacteria and some of them also interesting fungicidal and fungistatic activity.
Synthesis, structure, linear and nonlinear properties of tricyanofuran–terminated merocyanine dyes
Tillotson, John P.,Bogdanov, Georgii,Jucov, Evgheni V.,Khrustalev, Victor N.,Rigin, Sergei,Hales, Joel M.,Perry, Joseph W.,Timofeeva, Tatiana V.
, p. 146 - 154 (2019)
Structural and spectroscopic characteristics of merocyanine dyes are important because of their potential applications in optoelectronics and sensors. Herein we report synthesis, X-ray diffraction characterization of crystal structure, spectroscopic and NMR studies of four merocyanine dyes which, according to their strong donor-acceptor structure, exhibit a second order polarizability (β). Crystallographic studies demonstrated an almost planar structure of all molecules and indicated the occurrence of conformational changes in π-conjugated bridge between donor and acceptor. For three homologues similar packing modes, defined mostly by week C[sbnd]H?N interactions, were found in crystals. Bond length alternation (BLA) values have been evaluated using crystallographic and NMR data and have shown a correlation to their nonlinear optical activity. Second order polarizabilities for all compounds were measured using hyper Rayleigh scattering (HRS) in solution. It was found that the merocyanines studied exhibit very large second order polarizabilities (up to 4.1 10?27 esu), making them potentially useful for materials for second harmonic generation (SHG). Unfortunately, they do not demonstrate acentric packing of chromophores, which is required for SHG in the crystalline state, but may show promise for other applications such as poled polymer blends or for SHG sensing in biological environments.
Aromatic amines in organic synthesis. Part ii. p‐aminocinnamaldehydes
J?drzejewska, Beata,Pietrzak, Marek
, (2021)
Ten derivatives of p‐aminocinnamic aldehydes were prepared from the reaction of either aromatic amines with dimethylaminoacrolein or benzaldehydes with acetaldehyde. Their chemical structure and purity were verified by1H NMR,13C NMR and IR spectroscopic methods. We found that the synthesis applying dimethylaminoacrolein as the reagent gets better yields than the one based on the reaction with acetaldehyde. The yields of the cinnamic aldehydes varied according to the type of the amino group and the number and position of the substituents. The basic spectroscopic properties of the p‐aminocinnamic aldehydes are also described since the compounds may be a precursor for the synthesis of dyes for diverse applications, e.g., in medicine and optoelectronics.
Benzothiazolium Derivative-Capped Silica Nanocomposites for β-Amyloid ImagingIn Vivo
Ma, Lijun,Yang, Shu,Ma, Yufan,Chen, Yuzhi,Wang, Zhenguo,James, Tony D.,Wang, Xuefei,Wang, Zhuo
, p. 12617 - 12627 (2021/09/30)
Alzheimer’s disease (AD) is a neurodegenerative disease, and β-amyloid (Aβ) is believed to be a causative factor in AD pathology. The abnormal deposition of Aβ is believed to be responsible for progression of AD. In order to facilitate the imaging of Aβin vivo, suitable probe molecules with a near-infrared emission wavelength that can penetrate the blood-brain barrier (BBB) were utilized. The commercial fluorescent probe thioflavin-T (ThT) is used to image Aβ; however, because of its short emission wavelength and poor BBB penetration, ThT can only be usedin vitro. With this research, based on ThT, we design three fluorescent probes (SZIs) having a longer emission wavelength in order to image Aβ aggregates. SZIs with different numbers of double bonds respond to Aβ aggregates. The SZIs have a structure similar to ThT, and as such, the SZIs are also unable to penetrate the BBB. To deal with the problem, we develop nanocomposites (MSN-Lf@SZIs) to deliver SZIs into the brain of AD mouse and image Aβ successfully. These new nanocomposites are able to deliver the dyes into the brain and facilitate Aβ imagingin vivo.
Selective Rhodium-Catalyzed Hydroformylation of Terminal Arylalkynes and Conjugated Enynes to (Poly)enals Enabled by a π-Acceptor Biphosphoramidite Ligand
Zhao, Jiangui,Zheng, Xueli,Tao, Shaokun,Zhu, Yuxin,Yi, Jiwei,Tang, Songbai,Li, Ruixiang,Chen, Hua,Fu, Haiyan,Yuan, Maolin
supporting information, p. 6067 - 6072 (2021/08/16)
The hydroformylation of terminal arylalkynes and enynes offers a straightforward synthetic route to the valuable (poly)enals. However, the hydroformylation of terminal alkynes has remained a long-standing challenge. Herein, an efficient and selective Rh-catalyzed hydroformylation of terminal arylalkynes and conjugated enynes has been achieved by using a new stable biphosphoramidite ligand with strong π-acceptor capacity, which affords various important E-(poly)enals in good yields with excellent chemo- and regioselectivity at low temperatures and low syngas pressures.
NOVEL COMPOUNDS USEFUL AS NEAR-INFRARED FLUORESCENT PROBES SELECTIVELY BINDING TO TAU AGGREGATES AND METHOD OF PREPARING THE SAME
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Paragraph 0184-0188, (2021/08/20)
Disclosed are a compound with near-infrared fluorescence that selectively binds to tau aggregates, a method for preparing the same, a tau-targeting near-infrared fluorescent probe including the compound, a composition for detecting a tau fiber protein containing the near-infrared fluorescent probe as an active ingredient, and the use of the composition for the diagnosis of tauopathy. In particular, the compound does not bind to an amyloid beta protein and has high selectivity to a tau aggregate, specifically reported as an etiology of the initial state of tauopathy, thus being useful as a near-infrared fluorescent detector for detecting a tau fiber protein for early diagnosis of a tauopathy including Alzheimer's disease.
Heck Reactions of Acrolein or Enones and Aryl Bromides – Synthesis of 3-Aryl Propenals or Propenones and Consecutive Application in Multicomponent Pyrazole Syntheses
Stephan, Marvin,Panther, Jesco,Wilbert, Fabio,Ozog, Pauline,Müller, Thomas J. J.
supporting information, p. 2086 - 2092 (2020/03/23)
3-(Hetero)aryl propenals or propenones are efficiently prepared by a Heck reaction of (hetero)aryl bromides and acrolein or vinyl ketones using Beller's CataCXium Ptb ligand under Jeffery's and Fu's conditions. The formation of these three-carbon building blocks is embedded into consecutive three- and pseudo-four-component syntheses of 3-(hetero)aryl and 3,5-diarylpyrazoles with a broad substitution pattern in moderate to excellent yield.
Phosphorous acid promoted isomerization of propargyl alcohols to α,β-unsaturated carbonyl compounds
Gan, Xiaotang,Fu, Zuqi,Liu,Yan, Yani,Chen, Chao,Zhou, Yongbo,Dong, Jianyu
, (2019/07/12)
A metal-free and two-phase protocol for the Meyer-Schuster isomerization of propargyl alcohols to the corresponding α,β-unsaturated carbonyl compounds has been achieved in the presence of stoichiometric phosphorous acid aqueous solution, which produces the desired products in high yields with excellent stereoselectivity. Compared with the traditional methods, the procedure features broad scope of the substrates, mild conditions, and easy separation, providing an appealing alternative to the Meyer-Schuster reaction.
Palladium-Catalyzed Formylation of Alkenylzinc Reagents with S-(4-Nitrophenyl) Thioformate
Haraguchi, Ryosuke,Tanazawa, Sho-Go,Tokunaga, Naoya,Fukuzawa, Shin-Ichi
supporting information, p. 1761 - 1764 (2018/04/27)
We report the synthesis of enal compounds by palladium-catalyzed formylation of alkenylzinc reagents with S-(4-nitrophenyl) thioformate. Various functional groups were tolerated in the present reaction. 1H NMR experiments revealed that the products had a non-protected formyl group, which can be utilized for further C–C bond formation reactions. We successfully achieved the one-pot synthesis of a 1,5-diene-3-ol compound via sequential formylation and allylation.
Novel green-yellow-orange-red light emitting donor-π-acceptor type dyes based on 1,3-indandione and dimedone moieties
Malina, Ilze,Kampars, Valdis,Turovska, Baiba,Belyakov, Sergey
, p. 820 - 830 (2017/01/21)
Ten novel luminescent dyes containing 1,3-indandione or dimedone as electron acceptors, amino derivatives (dimethylamino, diphenylamino, julolidine and dibiphenylamino) as electron donor units and different length olefinic linkers (1-hydroxyallylidene or 1-hydroxypenta-2,4-dien-1-ylidene) are reported in this study. Newly synthesized compound structures are proven with X-ray analysis, 1H, 13C NMR spectroscopy and elemental analysis. The UV–Vis absorption, emission, solvatochromism, solvatofluorochromism, redox properties, as well as thermal stabilities and quantum chemical calculations of these dyes were systematically investigated to outline relation between structure and properties. These dyes exhibit moderate thermal decomposition temperatures above 200?°C, insignificant solvatochromism and positive, significant solvatofluorochromism, large Stokes shifts and green, yellow, orange and red light emission with quantum yields in range from 0.03 to 0.93 in non-polar solvents and in thin films. Quantum-chemical calculations (DFT) shows, that all dyes exhibit small HOMO/LUMO gaps from 2.77 to 3.22?eV, which is in agreement with experimental data.
