Tag: 200-300

Detection and Imaging of Aβ1-42 and Tau Fibrils by Redesigned Fluorescent X-34 Analogues was written by Zhang, Jun;Sandberg, Alexander;Konsmo, Audun;Wu, Xiongyu;Nystroem, Sofie;Nilsson, K. Peter R.;Konradsson, Peter;Le Vine, Harry III;Lindgren, Mikael;Hammarstroem, Per. And the article was included in Chemistry – A European Journal in 2018.SDS of cas: 148231-12-3 This article mentions the following:

The authors revisited the Congo red analog 2,5-bis(4′-hydroxy-3′-carboxy-styryl)benzene (X-34) to develop this highly fluorescent amyloid dye for imaging Alzheimer’s disease (AD) pathol. comprising Aβ and Tau fibrils. A selection of ligands with distinct optical properties were synthesized by replacing the central benzene unit of X-34, with other heterocyclic moieties. Full photophys. characterization was performed, including recording absorbance and fluorescence spectra, Stokes shift, quantum yield and fluorescence lifetimes. All ligands displayed high affinity towards recombinant amyloid fibrils of Aβ1-42 (13-300 nM K_d) and Tau (16-200 nM K_d) as well as selectivity towards the corresponding disease-associated protein aggregates in AD tissue. These ligands efficiently displaced X-34, but not Pittsburgh compound B (PiB) from recombinant Aβ1-42 amyloid fibrils, arguing for retained targeting of the Congo red type binding site. The authors foresee that the X-34 scaffold offers the possibility to develop novel high-affinity ligands for Aβ pathol. found in human AD brain in a different mode compared with PiB, potentially recognizing different polymorphs of Aβ fibrils. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3SDS of cas: 148231-12-3).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazines are volatile compounds that are used in the cosmetic, food, flavor, and fragrance industries. Pyrazines are chemical compounds (technically called “methoxypyrazines”) found in grape skin and stems that are responsible for many “green” flavors in wine. Levels of pyrazines are dependent on viticultural practices, climate, and grape variety.SDS of cas: 148231-12-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Derisking the Cu-Mediated ¹⁸F-Fluorination of Heterocyclic Positron Emission Tomography Radioligands was written by Taylor, Nicholas J.;Emer, Enrico;Preshlock, Sean;Schedler, Michael;Tredwell, Matthew;Verhoog, Stefan;Mercier, Joel;Genicot, Christophe;Gouverneur, Veronique. And the article was included in Journal of the American Chemical Society in 2017.HPLC of Formula: 1150566-27-0 This article mentions the following:

The compatibility of various heterocycles, particularly nitrogen heterocycles, towards the copper-mediated ¹⁸F-fluorination of aryl pinacolboronates with ¹⁸F-fluoride was determined using fluorination reactions of a model substrate in the presence of exogenous heterocycles and the fluorination reactions of substrates possessing heterocycles with fluorination on an attached aromatic ring or directly attached to the heterocycle of interest. Using this information, syntheses of seven ¹⁸F-labeled structurally complex pharmaceutically relevant heterocycle-containing mols. were designed and executed. The method may be useful in designing syntheses of other radiolabeled compounds and delineating the scope of utility of other radiolabeling methods. In the experiment, the researchers used many compounds, for example, Ethyl 6-chloroimidazo[1,2-b]pyridazine-3-carboxylate (cas: 1150566-27-0HPLC of Formula: 1150566-27-0).

Ethyl 6-chloroimidazo[1,2-b]pyridazine-3-carboxylate (cas: 1150566-27-0) belongs to pyrazine derivatives. Pyrazinesare six-membered aromatic heterocyclic organic compounds with two nitrogen atoms at 1,4-positions. Pyrazine is a weaker base (pKb = 13.4) than pyridine (pKb = 8.8), pyrimidine (pKb = 12.7). Pyrazines are chemical compounds (technically called “methoxypyrazines”) found in grape skin and stems that are responsible for many “green” flavors in wine. Levels of pyrazines are dependent on viticultural practices, climate, and grape variety.HPLC of Formula: 1150566-27-0

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Development of subnanomolar radiofluorinated (2-pyrrolidin-1-yl)imidazo[1,2-b]pyridazine pan-Trk inhibitors as candidate PET imaging probes was written by Bernard-Gauthier, Vadim;Bailey, Justin J.;Aliaga, Arturo;Kostikov, Alexey;Rosa-Neto, Pedro;Wuest, Melinda;Brodeur, Garrett M.;Bedell, Barry J.;Wuest, Frank;Schirrmacher, Ralf. And the article was included in MedChemComm in 2015.Recommanded Product: 1150566-27-0 This article mentions the following:

Dysregulation of tropomyosin receptor kinases (TrkA/B/C) expression and signalling is recognized as a hallmark of numerous neurodegenerative diseases including Parkinson’s, Huntington’s and Alzheimer’s disease. TrkA/B/C is known to drive tumorogensis and metastatic potential in a wide range of neurogenic and non-neurogenic human cancers. The development of suitable positron emission tomog. (PET) radioligands would allow an in vivo exploration of this versatile potential therapeutic target. Herein, the rational remodeling of the amide moiety of a 6-(2-(3-fluorophenyl)pyrrolidin-1-yl)imidazo[1,2-b]pyridazine-3-amide lead structure to accommodate efficient fluorine-18 labeling led to the identification of a series of fluorinated Trk inhibitors with picomolar IC₅₀. The ensuing representative radiolabeled inhibitors [¹⁸F]16 ([¹⁸F]-(±)-IPMICF6) and [¹⁸F]27 ([¹⁸F]-(±)-IPMICF10) constitute novel lead radioligands with about 2- to 3- orders of magnitude increased TrkB/C potencies compared to previous lead tracers and display favorable selectivity profiles and physicochem. parameters for translation into in vivo PET imaging agents. In the experiment, the researchers used many compounds, for example, Ethyl 6-chloroimidazo[1,2-b]pyridazine-3-carboxylate (cas: 1150566-27-0Recommanded Product: 1150566-27-0).

Ethyl 6-chloroimidazo[1,2-b]pyridazine-3-carboxylate (cas: 1150566-27-0) belongs to pyrazine derivatives. Pyrazines are volatile compounds that are used in the cosmetic, food, flavor, and fragrance industries. Pyrazine-based skeletons were incorporated into agents targeting a range of ailments. Many derivatives were synthesized and evaluated as potential cancer treatments.Recommanded Product: 1150566-27-0

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Dye-Sensitized Solar Cells Based on Functionally Separated D-π-A Dyes with 2-Cyanopyridine as an Electron-Accepting and Anchoring Group was written by Mao, Jiangyi;Wang, Dan;Liu, Shih-Hung;Hang, Yandi;Xu, Yaoyao;Zhang, Qiong;Wu, Wenjun;Chou, Pi-Tai;Hua, Jianli. And the article was included in Asian Journal of Organic Chemistry in 2014.Application In Synthesis of 5,8-Dibromoquinoxaline This article mentions the following:

Three functionally separated donor-π-acceptor (D-π-A) sensitizers CP-I-III with a cyano group as the electron-accepting group and a pyridine as the anchoring group have been developed for dye-sensitized solar cells (DSSCs). Significantly, the J_sc of CP-II, which contains a benzo[1,2,5]thiadiazole moiety, is much higher than those of CP-I and CP-III, which contain quinoxaline and [1,2,5]thiadiazolo[3,4-c]pyridine groups, resp. This is not only a result of the good photon absorption, but also effective intramol. charge transfer. The conversion efficiency (η) for CP-II-based DSSCs is 4.02 %, which is far better than that of CP-I and CP-III. Also, the η value for CP-II is much higher than that for the reference dye P-II with pyridine as anchoring group. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Application In Synthesis of 5,8-Dibromoquinoxaline).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazine derivatives have antitumor, antibiotic, anticonvulsant, antituberculous and diuretic effects as well as kinase, enzymatic and potent tubulin and FtsZ polymerization inhibitory activities. Pyrazines undergo nearly all of the same reactions as pyrimidines, from nucleophilic substitution (SNAr) to palladium-catalyzed cross coupling reactions.Application In Synthesis of 5,8-Dibromoquinoxaline

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Simple Access to Sol-Gel Precursors Bearing Fluorescent Aromatic Core Units was written by Hemgesberg, Maximilian;Ohlmann, Dominik M.;Schmitt, Yvonne;Wolfe, Monique R.;Mueller, Melanie K.;Erb, Benjamin;Sun, Yu;Goossen, Lukas J.;Gerhards, Markus;Thiel, Werner R.. And the article was included in European Journal of Organic Chemistry in 2012.SDS of cas: 148231-12-3 This article mentions the following:

Di-, tri-, and tetrathienyl-substituted polycyclic aromatic fluorophores were prepared from different aryldi-, aryltri-, or aryltetrahalides by a simple and fast Suzuki coupling. The reaction was optimized for the synthesis of the desired materials on multigram scale. The coupled products were converted into the corresponding iodides through iodination with N-iodosuccinimide. The iodides turned out to be versatile starting materials for applications, such as periodic mesoporous organosilica syntheses. They were converted into a variety of new trimethoxysilyl arenes by using a very efficient Pd-mediated C-Si cross-coupling, which was also extended to the corresponding thienyl bromides by using a dimeric Pd(I) catalyst. All compounds were characterized by ¹H NMR, ¹³C NMR, ²⁹Si NMR, and ATR-IR spectroscopy and HRMS. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3SDS of cas: 148231-12-3).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazine is a symmetrical molecule with point group D2h. Pyrazine is less basic than pyridine, pyridazine and pyrimidine. A large number of pyrazine derivatives are known for their antitumor, antibiotic, anticonvulsant, antituberculosis, and diuretic activities.SDS of cas: 148231-12-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Rational design for cooperative recognition of specific nucleobases using β-cyclodextrin-modified DNAs and fluorescent ligands on DNA and RNA scaffolds was written by Futamura, Akika;Uemura, Asuka;Imoto, Takeshi;Kitamura, Yusuke;Matsuura, Hirotaka;Wang, Chun-Xia;Ichihashi, Toshiki;Sato, Yusuke;Teramae, Norio;Nishizawa, Seiichi;Ihara, Toshihiro. And the article was included in Chemistry – A European Journal in 2013.Application In Synthesis of Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate This article mentions the following:

The authors propose a binary fluorimetric method for DNA and RNA anal. by the combined use of two probes rationally designed to work cooperatively. One probe is an oligonucleotide (ODN) conjugate bearing a β-cyclodextrin (β-CyD). The other probe is a small reporter ligand, which comprises linked mols. of a nucleobase-specific heterocycle and an environment-sensitive fluorophore. The heterocycle of the reporter ligand recognizes a single nucleobase displayed in a gap on the target labeled with the conjugate and, at the same time, the fluorophore moiety forms a luminous inclusion complex with nearby β-CyD. Three reporter ligands, MNDS (naphthyridine-dansyl linked ligand), MNDB (naphthyridine-DBD), and DPDB (pyridine-DBD), were used for DNA and RNA probing with 3′-end or 5′-end modified β-CyD-ODN conjugates. For the DNA target, the β-CyD tethered to the 3′-end of the ODN facing into the gap interacted with the fluorophore sticking out into the major groove of the gap site (MNDS and DPDB). Meanwhile the β-CyD on the 5′-end of the ODN interacted with the fluorophore in the minor groove (MNDB and DPDB). The results obtained by this study could be a guideline for the design of binary DNA/RNA probe systems based on controlling the proximity of functional mols. In the experiment, the researchers used many compounds, for example, Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate (cas: 1458-01-1Application In Synthesis of Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate).

Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate (cas: 1458-01-1) belongs to pyrazine derivatives. Pyrazines are part of several biologically active polycyclic compounds; examples are quinoxalines, phenazines; and the bio-luminescent natural products pteridines, flavins, and their derivatives. Pyrazines are chemical compounds (technically called “methoxypyrazines”) found in grape skin and stems that are responsible for many “green” flavors in wine. Levels of pyrazines are dependent on viticultural practices, climate, and grape variety.Application In Synthesis of Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Copolymers of Cyclopentadithiophene and Electron-Deficient Aromatic Units Designed for Photovoltaic Applications was written by Bijleveld, Johan C.;Shahid, Munazza;Gilot, Jan;Wienk, Martijn M.;Janssen, Rene A. J.. And the article was included in Advanced Functional Materials in 2009.SDS of cas: 148231-12-3 This article mentions the following:

Alternating copolymers based on cyclopentadithiophene (CPDT) and five different electron-deficient aromatic units with reduced optical band gaps are synthesized via Suzuki coupling. All polymers show a significant photovoltaic response when mixed with a fullerene acceptor. The frontier orbital levels of the new polymers are designed to minimize energy losses by increasing the open-circuit voltage with respect to the optical band gap, while maintaining a high coverage of the absorption with the solar spectrum. The best cells are obtained for a copolymer of CPDT and benzooxadiazole (BO) with a band gap of 1.47 eV. This cell gives a short-circuit current of 5.4 mA cm^-2, an open-circuit voltage of 0.78 V, and a fill factor of 0.6, resulting in a power conversion efficiency of about 2.5%. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3SDS of cas: 148231-12-3).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazinesare six-membered aromatic heterocyclic organic compounds with two nitrogen atoms at 1,4-positions. Pyrazine is a weaker base (pKb = 13.4) than pyridine (pKb = 8.8), pyrimidine (pKb = 12.7). Substituted pyrazines have been found as subunits of multiple synthetically constructed therapeutic agents, as well as several natural products.SDS of cas: 148231-12-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Preparation and properties of new π-conjugated poly(quinoxaline-5,8-diyl) and poly(2,3-diethylquinoxaline-5,8-diyl). Enhancement of electron-accepting properties of poly(arylenes) by introduction of imine nitrogen was written by Kanbara, Takaki;Yamamoto, Takakazu. And the article was included in Macromolecules in 1993.Computed Properties of C8H4Br2N2 This article mentions the following:

Reactions of 5,8-dibromoquinoxaline and 5,8-dibromo-2,3-diethylquinoxaline with a 0-valent Ni complex give poly(quinoxaline-5,8-diyl) (I) and poly(2,3-diethylquinoxaline-5,8-diyl), resp. These polymers are easily converted into elec. conducting materials by chem. and electrochem. reductions Comparison of redox potentials for the n-doping and undoping of I with those of poly(naphthalene-1,4-diyl) and poly(quinoline-5,8-diyl) indicates that introduction of imine N in the recurring naphthalene-like arylene ring leads to the enhancement of the electron-accepting properties of the poly(arylene)s with change of the reducing potential by about 0.35 V per each of the imine N. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Computed Properties of C8H4Br2N2).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazines are part of several biologically active polycyclic compounds; examples are quinoxalines, phenazines; and the bio-luminescent natural products pteridines, flavins, and their derivatives. Pyrazine and a variety of alkylpyrazines are flavor and aroma compounds found in baked and roasted goods. Tetramethylpyrazine (also known as ligustrazine) is reported to scavenge superoxide anion and decrease nitric oxide production in human Granulocytes.Computed Properties of C8H4Br2N2

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Light-emitting properties of donor-acceptor and donor-acceptor-donor dyes in solution, solid, and aggregated states: structure-property relationship of emission behavior was written by Ishi-i, Tsutomu;Ikeda, Kei;Ogawa, Michiaki;Kusakaki, Yutarou. And the article was included in RSC Advances in 2015.Safety of 5,8-Dibromoquinoxaline This article mentions the following:

In this paper, the authors report a systematic study on the light-emitting behavior of a series of triphenylamine-based donor-acceptor-type dyes in the solution and solid states as well as in the aggregated state in polar aqueous media. The emission band shifted bathochromically along with the decrease in the fluorescence quantum yield as the solvent polarity was increased from nonpolar cyclohexane to polar DMF. In a THF/water medium, the emission was quenched in a low water volume, whereas the emission was recovered and increased in a high water volume In a low water volume, the dye mols. exist in a monomeric form, and the fluorescence quenching increases with increasing water fraction, similar to that observed in the solvent-polarity-dependence study. In contrast, the dye mols. aggregated in a high water volume This is probably because the inside of aggregates is less polar than the outside, thus preventing nonradiative deactivation and recovering the emission. This unusual emission was achieved by triphenylamine-based dyes containing a relatively strong acceptor moiety such as quinoxaline, benzothiadiazole, and thiadiazolopyridine, providing longer-wavelength red and near-IR emission. In the benzothiadiazole-based dyes, when the Ph groups in the donor moieties were replaced with Me groups, the fluorescence quantum yield decreased, indicating that the triphenylamine donor moiety is suitable for emission in the aggregated state. The nonplanar structure of triphenylamine disrupts an ordered packing and produces a less-ordered spherical aggregate, leading to an efficient light emission even in polar aqueous media. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Safety of 5,8-Dibromoquinoxaline).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazines are volatile compounds that are used in the cosmetic, food, flavor, and fragrance industries. Pyrazines undergo nearly all of the same reactions as pyrimidines, from nucleophilic substitution (SNAr) to palladium-catalyzed cross coupling reactions.Safety of 5,8-Dibromoquinoxaline

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Determination and identification of amiloride in human urine by high-performance liquid chromatography and gas chromatography-mass spectrometry was written by Bi, Honggang;Cooper, Sam F.;Cote, Michel G.. And the article was included in Journal of Chromatography, Biomedical Applications in 1992.Application of 1458-01-1 This article mentions the following:

A simple and sensitive high-performance liquid chromatog. method was developed to screen and determine amiloride (I) in human urine. The detection limit of the method is 0.12 μg/mL and the recovery of amiloride from urine was 80.4-85.5% at different concentration The coefficients of variation were less than 2.8 and 4.4% for intra- and inter-assays, resp. Total urinary excretion of I in 24 h after oral administration of 5 mg or 15 mg of I ranged from 22.0 to 33.3% of the total dose for three different subjects. I could be detected in urine up to at least 44 h after a 5-mg dose and 72 h after a 15-mg dose. A gas chromatog.-mass spectrometric (GC-MS) confirmatory method was established based on the methanolysis of I to Me 3,5-diamino-6-chloropyrazinecarboxylate (II). The di-N-trimethylsilyl derivative of II showed very good GC-MS properties and provided reliable structure information for confirmation anal. of I. This is the first time that a reliable GC-MS method has been reported for the detection of urinary I. In the experiment, the researchers used many compounds, for example, Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate (cas: 1458-01-1Application of 1458-01-1).

Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate (cas: 1458-01-1) belongs to pyrazine derivatives. Pyrazines are part of several biologically active polycyclic compounds; examples are quinoxalines, phenazines; and the bio-luminescent natural products pteridines, flavins, and their derivatives. Pyrazine and a variety of alkylpyrazines are flavor and aroma compounds found in baked and roasted goods. Tetramethylpyrazine (also known as ligustrazine) is reported to scavenge superoxide anion and decrease nitric oxide production in human Granulocytes.Application of 1458-01-1

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem