Day: October 13, 2022

In 2019,Chemical Communications (Cambridge, United Kingdom) included an article by Sang, Zitai; Lu, Yongping; Zhou, Yuanzheng; Ju, Yuan; An, Qi; Shen, Silan; Shi, Jianyou; He, Jun; Yang, Tao; Luo, Youfu. Related Products of 2510-22-7. The article was titled 《Efficient discovery of novel antimicrobials through integration of synthesis and testing in crude ribosome extract》. The information in the text is summarized as follows:

By coupling in situ [2+3] Huisgen cycloaddition with an in vitro transcription/translation luminescence assay in a crude ribosomal extract, a robust and accurate high-throughput platform was successfully developed and applied for efficient identification of novel structural types of ribosomal inhibitors with antimicrobial activity against drug-resistant bacteria. The experimental part of the paper was very detailed, including the reaction process of 4-Ethynylpyridine(cas: 2510-22-7Related Products of 2510-22-7)

4-Ethynylpyridine(cas: 2510-22-7) belongs to pyridine. In industry and in the lab, pyridine is used as a reaction solvent, particularly when its basicity is useful, and as a starting material for synthesizing some herbicides, fungicides, and antiseptics.Related Products of 2510-22-7

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

In 2019,Journal of the American Chemical Society included an article by Fernandez, Estefania; Rivero-Crespo, Miguel A.; Dominguez, Irene; Rubio-Marques, Paula; Oliver-Meseguer, Judit; Liu, Lichen; Cabrero-Antonino, Maria; Gavara, Rafael; Hernandez-Garrido, Juan C.; Boronat, Mercedes; Leyva-Perez, Antonio; Corma, Avelino. Category: pyridine-derivatives. The article was titled 《Base-Controlled Heck, Suzuki, and Sonogashira Reactions Catalyzed by Ligand-Free Platinum or Palladium Single Atom and Sub-Nanometer Clusters》. The information in the text is summarized as follows:

The assumption that oxidative addition is the key step during the cross-coupling reaction of aryl halides has led to the development of a plethora of increasingly complex metal catalysts, thereby obviating in many cases the exact influence of the base, which is a simple, inexpensive, and necessary reagent for this paramount transformation. Here, a combined exptl. and computational study shows that the oxidative addition is not the single kinetically relevant step in different cross-coupling reactions catalyzed by sub-nanometer Pt or Pd species, since the reactivity control is shifted toward subtle changes in the base. The exposed metal atoms in the cluster cooperate to enable an extremely easy oxidative addition of the aryl halide, even chlorides, and allow the base to bifurcate the coupling. With sub-nanometer Pd species, amines drive to the Heck reaction, carbonate drives to the Sonogashira reaction, and phosphate drives to the Suzuki reaction, while for Pt clusters and single atoms, good conversion is only achieved using acetate as a base. This base-controlled orthogonal reactivity with ligand-free catalysts opens new avenues in the design of cross-coupling reactions in organic synthesis.2-Pyridinylboronic acid(cas: 197958-29-5Category: pyridine-derivatives) was used in this study.

2-Pyridinylboronic acid(cas: 197958-29-5) belongs to pyridine. Pyridine’s structure is isoelectronic with that of benzene, but its properties are quite different. Pyridine is completely miscible with water, whereas benzene is only slightly soluble. Like all hydrocarbons, benzene is neutral (in the acid–base sense), but because of its nitrogen atom, pyridine is a weak base.Category: pyridine-derivatives

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

In 2019,Journal of the Brazilian Chemical Society included an article by de Mello, Murilo B. M.; de Oliveira, Antonio A. F.; de Oliveira, Caroline L.; Ultramari, Mariah A.; Gama, Fernando H. S.; Mascarello, Alessandra; Guimaraes, Cristiano R. W.; de Freitas, Miller N.; Cunha, Carlos E.; Lourenco, Tiago C.; Ferreira, Fernanda P.; Lopesa, Joao L. C.; Clososki, Giuliano C.. Category: pyridine-derivatives. The article was titled 《Characterization and in silico mutagenic assessment of a new betahistine degradation impurity》. The information in the text is summarized as follows:

Currently, the pharmaceutical industry devotes great attention to drug degradation products because these compounds can offer risks to patients. A previous degradation study of betahistine (N-α-methyl-2-pyridylethylamine) conducted under different stress conditions detected three main impurities named A, B and C. Degradation products were analyzed by high-resolution mass spectrometry in electrospray source and time of flight analyzer (ESI-TOF) and NMR (NMR). Impurity mutagenicity was evaluated by Derek Nexus and Sarah Nexus softwares. Liquid chromatog. hyphenate with tandem mass spectrometry (LC-MS/MS) anal. of the betahistine forced degradation sample indicated the presence of a new impurity, which was named impurity C1. 2D NMR experiments allowed the complete structural characterization of the new entity. The active pharmaceutical ingredient and degradation impurities were classified as inactive in the in silico mutagenic studies. Systematic investigation of a forced degradation sample led to the characterization of a new betahistine impurity. The in silico mutagenicity study of the betahistine degradation impurities may be useful in the risk assessment of the drug products. In the experimental materials used by the author, we found 2-(2-Hydroxyethyl)pyridine(cas: 103-74-2Category: pyridine-derivatives)

2-(2-Hydroxyethyl)pyridine(cas: 103-74-2) belongs to pyridine. Pyridine’s structure is isoelectronic with that of benzene, but its properties are quite different. Pyridine is completely miscible with water, whereas benzene is only slightly soluble. Like all hydrocarbons, benzene is neutral (in the acid–base sense), but because of its nitrogen atom, pyridine is a weak base.Category: pyridine-derivatives

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

In 2019,European Journal of Medicinal Chemistry included an article by Martin-Encinas, Endika; Rubiales, Gloria; Knudssen, Birgitta R.; Palacios, Francisco; Alonso, Concepcion. Synthetic Route of C5H5BrN2. The article was titled 《Straightforward synthesis and biological evaluation as topoisomerase I inhibitors and antiproliferative agents of hybrid chromeno[4,3-b][1,5]naphthyridines and chromeno[4,3-b][1,5]naphthyridin-6-ones》. The information in the text is summarized as follows:

Hybrid tetrahydrochromeno[4,3-b][1,5]naphthyridines I [R1 = H, F, Me; R2 = H, OMe; X = CH2], tetrahydrochromeno[4,3-b][1,5]naphthyridinones I [R1 = H, F; R2 = H, OMe, Br; X = C(O)], chromeno[4,3-b][1,5]naphthyridines II [X = CH2] and chromeno[4,3-b][1,5]naphthyridinones II [R3 = H, F, Me; R4 = H, OMe, Br; R5 = Ph, 4-MeOC6H4, 3,4-F2C6H3; Z = CH2, C(O)] were synthesized and evaluated as topoisomerase I inhibitors and antiproliferative agents. The synthetic route involved an intramol. Povarov [4 + 2]-cycloaddition of functionalized aldimines obtained by the condensation of 3-aminopyridine and aldehydes containing a double or triple carbon-carbon bond in ortho position and allowed the selective generation of three stereogenic centers. The subsequent dehydrogenation of the fused tetrahydrochromeno[4,3-b][1,5]naphthyridines I [X = CH2] and tetrahydrochromeno[4,3-b][1,5]naphthyridin-6-ones I [X = C=O] led to the formation of the corresponding tetracyclic chromeno[4,3-b][1,5]naphthyridine derivatives II [X = CH2] and chromeno[4,3-b][1,5]naphthyridin-6-ones II [X = C=O] in quant. yields. Some of the prepared products showed activity as inhibitors of topoisomerase I (TopI). Addnl., the cytotoxic behavior of these compounds was studied and the absence of cytotoxicity was observed against non-cancerous lung fibroblasts cell line (MRC5). Compound tetrahydrochromeno[4,3-b][1,5]naphthyridine I [R1 = R3 = H, R2 = Ph, X = CH2] showed excellent cytotoxic activity with a IC50 value of 1.03 ± 0.30 μM against the A549 cell line and a IC50 value of 1.75 ± 0.20 μM against the SKOV03 cell line. The obtained results point to these compounds as good antiproliferative candidates. Further, the physicochem. properties of these hybrid compounds were evaluated and could be considered as candidates for drugs with promising pharmacotherapeutic profiles similar to those of currently used drugs. In addition, docking experiments showed the possible mode of binding of these compounds and according to these studies the structural part corresponding to chromene or coumarin seems to play an important role in the interaction with the active site. The results came from multiple reactions, including the reaction of 6-Bromopyridin-3-amine(cas: 13534-97-9Synthetic Route of C5H5BrN2)

6-Bromopyridin-3-amine(cas: 13534-97-9) belongs to anime. Halogenation, in which one or more hydrogen atoms of an amine is replaced by a halogen atom, occurs with chlorine, bromine, and iodine, as well as with some other reagents, notably hypochlorous acid (HClO). With primary amines the reaction proceeds in two stages, producing N-chloro- and N,N-dichloro-amines, RNHCl and RNCl2, respectively. With tertiary amines, an alkyl group may be displaced by a halogen.Synthetic Route of C5H5BrN2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

The author of 《Fluorescence Lifetime Imaging of p-tau Protein in Single Neuron with a Highly Selective Fluorescent Probe》 were Ge, Lihong; Tian, Yang. And the article was published in Analytical Chemistry (Washington, DC, United States) in 2019. HPLC of Formula: 1539-42-0 The author mentioned the following in the article:

Hyperphosphorylated tau (p-tau) protein is one of the key markers of Alzheimer’s disease (AD). However, a lack of anal. methods for p-tau protein with high selectivity and accuracy is the bottleneck to understand the pathol. processes of AD. In the present work, a highly selective fluorescence lifetime imaging microscopic (FLIM) probe (τ-p-tau) was rationally designed and developed for determination of p-tau protein, in which binuclear zinc units were designed as the recognition groups, and an improved cyanine was synthesized as the dye unit. The FLIM measurement is independent of the concentration of fluorescent probes, irradiation light sources, and measurement environments. Meanwhile, the developed τ-p-tau probe demonstrated strong affinity toward p-tau protein, thus enhancing the selectivity of determination of p-tau protein against Aβ, Aβ fibril, tau, protein kinases, ATP, and so on. The fluorescence lifetime of τ-p-tau probe showed a good linearity with the concentration of p-tau protein from 1.0 to 5.0 μM with a low detection limit of 85.15±0.03 nM. The response time of the present probe for p-tau protein was estimated to be less than 6.2 s. Furthermore, taking the advantages of low toxicity and good biocompatibility, the developed probe was successfully applied to monitor the fluctuation of concentration of p-tau protein by FLIM imaging at single neuron level. It was found that the concentration of p-tau protein inside live neurons obviously changed upon oxidative stress. In the experimental materials used by the author, we found Bis(pyridin-2-ylmethyl)amine(cas: 1539-42-0HPLC of Formula: 1539-42-0)

Bis(pyridin-2-ylmethyl)amine(cas: 1539-42-0) is a secondary amine with two picolyl substituents. As a tridentate ligand this compound provides three nitrogen donors that affords good selectivity for Zn2+ over biologically relevant metals such as Na+, K+, Mg2+ and Ca2+, and leaves coordination sites free for anion binding. HPLC of Formula: 1539-42-0

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

《The Suzuki-Miyaura Cross-Coupling as the Key Step in the Synthesis of 2-Aminobiphenyls and 2,2′-Diaminobiphenyls: Application in the Synthesis of Schiff Base Complexes of Zn》 was published in European Journal of Organic Chemistry in 2020. These research results belong to Hylland, Knut Tormodssoenn; Oien-Odegaard, Sigurd; Tilset, Mats. Computed Properties of C5H3Br2N The article mentions the following:

2-Nitrophenylboronic acids serve as interesting starting materials for the construction of biphenyl- and terphenyl-based amines if subjected to the Suzuki-Miyaura reaction. Unfortunately, these boronic acids suffer from low reactivity in Suzuki reactions, alongside their low stability in the presence of Pd. Herein, a general method for the construction of 2-nitro-substituted bi- and terphenyls is presented, with special emphasis on the synthesis of 2-amino-2′-nitrobi- and terphenyls. Comparisons are made with other boronic acids that have some of the aforementioned issues. Finally, the application of the obtained 2-amino-2′-nitrobi- and terphenyls as starting materials for the synthesis of bi- and terphenyl based di- and triamines is encountered for, with emphasis on the use of these amines as precursors for Schiff base ligands. In addition, the synthesis of some Zn complexes of these ligands is presented. In the part of experimental materials, we found many familiar compounds, such as 2,5-Dibromopyridine(cas: 624-28-2Computed Properties of C5H3Br2N)

2,5-Dibromopyridine(cas: 624-28-2) belongs to pyridine. In industry and in the lab, pyridine is used as a reaction solvent, particularly when its basicity is useful, and as a starting material for synthesizing some herbicides, fungicides, and antiseptics.Computed Properties of C5H3Br2N

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

《Efficient Transfer Hydrogenation of Ketones Catalyzed by a Phosphine-Free Cobalt-NHC Complex》 was written by Ibrahim, Jessica Juweriah; Reddy, C. Bal; Fang, Xiaolong; Yang, Yong. Computed Properties of C7H7NO And the article was included in European Journal of Organic Chemistry in 2020. The article conveys some information:

A simple phosphine-free cobalt-NHC pincer complex was synthesized and used for the transfer hydrogenation of ketones with 2-propanol as hydrogen donor. A broad range of ketones varying from aromatic, aliphatic and heterocyclic were effectively reduced to their corresponding alcs. in moderate to excellent yields with good tolerance of functional groups. In the part of experimental materials, we found many familiar compounds, such as 4-Acetylpyridine(cas: 1122-54-9Computed Properties of C7H7NO)

4-Acetylpyridine(cas: 1122-54-9) belongs to pyridine. Pyridine is a relatively complex molecule and exhibits a number of different bands in IR spectra. Among others, the bands characterizing the ν8a and ν19b modes have been found to be sensitive to the coordination or protonation of the molecule. Note that the band that is diagnostic for the PyH+ ion at about 1545 cm− 1 (ν19b mode) does not overlap with any of the other bands.Computed Properties of C7H7NO

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

《Imaging and therapeutic applications of Zn(II)-cryptolepine-curcumin molecular probes in cell apoptosis detection and photodynamic therapy》 was written by Qin, Qi-Pin; Wei, Zu-Zhuang; Wang, Zhen-Feng; Huang, Xiao-Ling; Tan, Ming-Xiong; Zou, Hua-Hong; Liang, Hong. Electric Literature of C12H13N3 And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2020. The article conveys some information:

Novel red Zn(II) complex-based fluorescent probes featuring cryptolepine-curcumin derivatives, namely, [Zn(BQ)Cl2] (BQ-Zn) and [Zn(BQ)(Cur)]Cl (BQCur-Zn), were developed for the simple and fluorescent label-free detection of apoptosis, an important biol. process. The probes could synergistically promote mitochondrion-mediated apoptosis and enhance tumor therapeutic effects in vitro and vivo. The experimental part of the paper was very detailed, including the reaction process of Bis(pyridin-2-ylmethyl)amine(cas: 1539-42-0Electric Literature of C12H13N3)

Bis(pyridin-2-ylmethyl)amine(cas: 1539-42-0) is a secondary amine with two picolyl substituents. The compound is a tridentate ligand in coordination chemistry and commonly used to produce Zn-based chemosensors/probes, such as Zinpry.Electric Literature of C12H13N3

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

《Aggregation-Induced Electrochemiluminescence Bioconjugates of Apoferritin-Encapsulated Iridium(III) Complexes for Biosensing Application》 was written by Yang, Lei; Sun, Xu; Wei, Dong; Ju, Huangxian; Du, Yu; Ma, Hongmin; Wei, Qin. Recommanded Product: 94928-86-6 And the article was included in Analytical Chemistry (Washington, DC, United States) in 2021. The article conveys some information:

An intriguing aggregation-induced electrochemiluminescence (AIECL) bioconjugate was fabricated by encapsulating fac-tris(2-phenylpyridine)iridium(III) complexes [Ir(ppy)3] in the apoferritin (apoFt) cavity for biosensing application. Based on the unique pH-dependent disassembly/reassembly characteristic of apoFt, approx. 44.3 mols. of Ir(ppy)3 aggregated in the single cavity through both intermol. π-π-stacking interactions and hydrogen bonds that efficiently restricted the intramol. motions to trigger the AIECL effect. Compared to monomers, Ir(ppy)3 aggregates performed 5.3-fold-enhanced ECL emission using tri-n-propylamine (TPrA) as a coreactant. The fabricated Ir(ppy)3@apoFt bioconjugate was flexibly labeled with a detection antibody to act as a transducer for the immunosensor construction. To further catalyze the ECL reaction between the reductive TPrA• and the oxidative Ir(ppy)3+• radicals, a conductive and electroactive substrate of Fe2N and gold nanoparticle-codecorated reduced graphene oxide (Fe2N/rGO/Au) was established to incubate the capture antibody. Therefore, a “”signal on”” immunosensor was developed for sensitive assay of cytokeratin 19 fragment 21-1 (CYFRA 21-1), in which good linearity ranging from 1 pg/mL to 50 ng/mL with a low detection limit of 0.43 pg/mL (S/N = 3) was obtained. This study shares with an inspiration of using apoFt to design iridium(III)-based AIECL emitters, which will expand more possibilities of organic iridium(III) complexes in establishing innovative ECL immunoassays. In the experiment, the researchers used fac-Tris(2-phenylpyridine)iridium(cas: 94928-86-6Recommanded Product: 94928-86-6)

fac-Tris(2-phenylpyridine)iridium(cas: 94928-86-6) belongs to pyridine. Pyridine is widely used in the precursor to agrochemicals and pharmaceuticals. Also, it is used as an important reagent and organic solvent.Recommanded Product: 94928-86-6

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Stevenson, Bernard G.; Spielvogel, Ethan H.; Loiaconi, Emily A.; Wambua, Victor Mulwa; Nakhamiyayev, Roman V.; Swierk, John R. published their research in Journal of the American Chemical Society in 2021. The article was titled 《Mechanistic Investigations of an α-Aminoarylation Photoredox Reaction》.Electric Literature of C33H24IrN3 The article contains the following contents:

While photoredox catalysis continues to transform modern synthetic chem., detailed mechanistic studies involving direct observation of reaction intermediates and rate constants are rare. By use of a combination of steady state photochem. measurements, transient laser spectroscopy, and electrochem. methods, an α-aminoarylation mechanism that is the inspiration for a large number of photoredox reactions was rigorously characterized. Despite high product yields, the external quantum yield (QY) of the reaction remained low (15-30%). By use of transient absorption spectroscopy, productive and unproductive reaction pathways were identified and rate constants assigned to develop a comprehensive mechanistic picture of the reaction. The role of the cyanoarene, 1,4-dicyanobenzne, was found to be unexpectedly complex, functioning both as initial proton acceptor in the reaction and as a neutral stabilizer for the 1,4-dicyanobenzene radical anion. Finally, kinetic modeling was utilized to analyze the reaction at an unprecedented level of understanding. This modeling demonstrated that the reaction is limited not by the kinetics of the individual steps but instead by scattering losses and parasitic absorption by a photochem. inactive donor-acceptor complex. In the experiment, the researchers used many compounds, for example, fac-Tris(2-phenylpyridine)iridium(cas: 94928-86-6Electric Literature of C33H24IrN3)

fac-Tris(2-phenylpyridine)iridium(cas: 94928-86-6) belongs to pyridine. Pyridine is widely used in the precursor to agrochemicals and pharmaceuticals. Also, it is used as an important reagent and organic solvent.Electric Literature of C33H24IrN3

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem