Day: October 24, 2022

Li, Xin; Cun, Lin-Feng; Gong, Liu-Zhu; Mi, Ai-Qiao; Jiang, Yao-Zhong published their research in Tetrahedron: Asymmetry on December 12 ,2003. The article was titled 《The enantioselective diethylzinc addition to imines catalyzed by chiral Cu(II)-oxazoline complexes》.Reference of 2,6-Bis((4S,5S)-4,5-diphenyl-4,5-dihydrooxazol-2-yl)pyridine The article contains the following contents:

A series of copper complexes of chiral bisoxazolines has been applied in the catalytic diethylzinc addition to N-sulfonyl imines. It has been found that the tridentate ligands,.e.g., I, provided higher enantioselectivity than bidentate ones. Addition of 4 A mol. sieves to the reaction system benefits the enantioselectivity. The optimal procedure for diethylzinc addition to different imines resulted in moderate yields and enantioselectivities of up to 82% ee. In the experiment, the researchers used many compounds, for example, 2,6-Bis((4S,5S)-4,5-diphenyl-4,5-dihydrooxazol-2-yl)pyridine(cas: 410092-98-7Reference of 2,6-Bis((4S,5S)-4,5-diphenyl-4,5-dihydrooxazol-2-yl)pyridine)

2,6-Bis((4S,5S)-4,5-diphenyl-4,5-dihydrooxazol-2-yl)pyridine(cas: 410092-98-7) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. Reference of 2,6-Bis((4S,5S)-4,5-diphenyl-4,5-dihydrooxazol-2-yl)pyridine Pyridine has a conjugated system of six π electrons that are delocalized over the ring.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

The author of 《Design and Activity of Novel Oxadiazole Based Compounds That Target Poly(ADP-ribose) Polymerase》 were Vishwanath, Divakar; Girimanchanaika, Swamy S.; Dukanya, Dukanya; Rangappa, Shobith; Yang, Ji-Rui; Pandey, Vijay; Lobie, Peter E.; Basappa, Basappa. And the article was published in Molecules in 2022. Name: (6-Chloro-5-methylpyridin-3-yl)boronic acid The author mentioned the following in the article:

Novel PARP inhibitors with selective mode-of-action have been approved for clin. use. Herein, oxadiazole based ligands that are predicted to target PARP-1 have been synthesized and screened for the loss of cell viability in mammary carcinoma cells, wherein seven compounds were observed to possess significant IC50 values in the range of 1.4 to 25 μM. Furthermore, compound 5u, inhibited the viability of MCF-7 cells with an IC50 value of 1.4μM, when compared to Olaparib (IC50 = 3.2 μM). Compound 5s also decreased cell viability in MCF-7 and MDA-MB-231 cells with IC50 values of 15.3 and 19.2 μM, resp. Treatment of MCF-7 cells with compounds 5u and 5s produced PARP cleavage, H2AX phosphorylation and CASPASE-3 activation comparable to that observed with Olaparib. Compounds 5u and 5s also decreased foci-formation and 3D Matrigel growth of MCF-7 cells equivalent to or greater than that observed with Olaparib. Finally, in silico anal. demonstrated binding of compound 5s towardsthe catalytic site of PARP-1, indicating that these novel oxadiazoles synthesized herein may serve as exemplars for the development of new therapeutics in cancer. In the part of experimental materials, we found many familiar compounds, such as (6-Chloro-5-methylpyridin-3-yl)boronic acid(cas: 1003043-40-0Name: (6-Chloro-5-methylpyridin-3-yl)boronic acid)

(6-Chloro-5-methylpyridin-3-yl)boronic acid(cas: 1003043-40-0) belongs to pyridine. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. As ligands, solvents, and catalysts they facilitate reactions; thus descriptions of these new ligands and their applications abound each year.Name: (6-Chloro-5-methylpyridin-3-yl)boronic acid

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Xu, Yinghua; Ding, Xufen; Ma, Hongxing; Chu, Youqun; Ma, Chunan published an article in Electrochimica Acta. The title of the article was 《Selective hydrodechlorination of 3,5,6-trichloropicolinic acid at an activated silver cathode: Synthesis of 3,5-dichloropicolinic acid》.Related Products of 40360-44-9 The author mentioned the following in the article:

Electrochem. reduction of 3,5,6-trichloropicolinic acid (3,5,6-T) at glassy carbon, Ni, Cu, and Ag cathodes in aqueous solutions at different pH values was studied. Probably the selectivity of the reduction strongly depends on the cathode materials used and the pH of the aqueous solutions A high selectivity for the hydrodechlorination of 3,5,6-T to 3,5-dichloropicolinic acid (3,5-D) was achieved exclusively at an activated Ag cathode and at pH 3: a selectivity of 95% at 42% conversion under potentiostatic mode and a selectivity of 89% at 88% conversion under intentiostatic mode. An explanation is proposed for this high selectivity. After reading the article, we found that the author used 3,5,6-Trichloropicolinic acid(cas: 40360-44-9Related Products of 40360-44-9)

3,5,6-Trichloropicolinic acid(cas: 40360-44-9) belongs to pyridine. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. As ligands, solvents, and catalysts they facilitate reactions; thus descriptions of these new ligands and their applications abound each year.Related Products of 40360-44-9

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

In 2009,Xiao, Fangliang; Liu, Yu; Hu, Zhengyong; Gan, Quan; Wang, Lei; Wen, Zhonglin; Zhu, Meixiang; Zhu, Weiguo published 《Synthesis of bicyclometalated iridium complex containing 1,3,4-oxadiazole-based picolinic acid derivative and its optoelectronic properties in polymer light-emitting devices》.Synthetic Metals published the findings.Formula: C7H6BrNO2 The information in the text is summarized as follows:

A picolinic acid (Pic) derivative I bearing a 1,3,4-oxadiazole unit and its bicyclometalated iridium complex (PhOXD)2Ir(BuPhOXD-Pic) were synthesized and characterized, in which BuPhOXD-Pic (I) is 5-(4′-(5”-(4-tert-butylphenyl)-1”,3”,4”-oxadiazol-2”-yl) phenyl) picolinic acid and PhOXD is 2,5-diphenyl-1,3,4-oxadiazole. The optoelectronic properties of this iridium complex were studied in the double-layer polymer light-emitting devices using a blend of poly (9,9-dioctylfluorene) and 5-biphenyl-2-(4-tert-butyl) phenyl-1,3,4-oxadiazole as a host matrix. This complex exhibited a maximum luminance efficiency of 7.7 cd/A at 5.6 mA/cm2 and a peak brightness of 5288 cd/m2 at 153.7 mA/cm2 in the devices. Compared to the (PhOXD)2Ir(Pic) complex, the (PhOXD)2Ir(BuPhOXD-Pic) complex displays better optoelectronic properties in the devices. This study provides a convenient way to improve the optoelectronic properties of iridium complexes by modifying an ancillary ligand of picolinic acid with an 1,3,4-oxadiazole unit. The experimental process involved the reaction of Methyl 5-bromopicolinate(cas: 29682-15-3Formula: C7H6BrNO2)

Methyl 5-bromopicolinate(cas: 29682-15-3) belongs to pyridine. When pyridine is adsorbed on oxide surfaces or in porous materials, the following species are commonly observed: (i) pyridine coordinated to Lewis acid sites, (ii) pyridine H-bonded to weakly acidic hydroxyls, and (iii) protonated pyridine. At high coverage, physisorbed pyridine and protonated dimers can also be observed.Formula: C7H6BrNO2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

In 2017,Isley, Nicholas A.; Wang, Ye; Gallou, Fabrice; Handa, Sachin; Aue, Donald H.; Lipshutz, Bruce H. published 《A Micellar Catalysis Strategy for Suzuki-Miyaura Cross-Couplings of 2-Pyridyl MIDA Boronates: No Copper, in Water, Very Mild Conditions》.ACS Catalysis published the findings.Recommanded Product: 53939-30-3 The information in the text is summarized as follows:

Suzuki-Miyaura cross-coupling of 2-pyridyl N-methyliminodiacetic acid (MIDA) boronates with aryl chlorides and bromides was carried out in the complete absence of copper by attenuation of the Lewis basicity associated with the pyridyl nitrogen using selected substituents (e.g., fluorine or chlorine) on the ring. Coupling of substituted 2-pyridinyl MIDA boronates was performed using Pd(dtbpf)Cl2 as catalyst and DIPEA in an aqueous micellar suspension of the surfactant TPGS-750-M. Dehalogenation of the halopyridines using Ni(OAc)2 and 1,10-phenanthroline as catalysts and pyridine and NaBH4, Suzuki-Miyaura coupling with aryl or heteroaryl bromides in the absence of addnl. palladium catalyst, or nucleophilic aromatic substitution of the halopyridines with dimethylamine or morpholine yielded substituted pyridines. Computational data suggest that the major role played by electron-withdrawing substituents in promoting Suzuki-Miyaura cross-couplings of 2-pyridinyl MIDA boronates in the absence of copper is to slow the rate of protodeboronation of the intermediate 2-pyridylboronic acids. 2-Pyridinylboronic acids were generated by controlled release of 2-pyridinyl MIDA boronates in D2O and underwent protodeboronation slowly under those conditions. After reading the article, we found that the author used 5-Bromo-2-chloropyridine(cas: 53939-30-3Recommanded Product: 53939-30-3)

5-Bromo-2-chloropyridine(cas: 53939-30-3) belongs to pyridine. Pyridines form stable salts with strong acids. Pyridine itself is often used to neutralize acid formed in a reaction and as a basic solvent. Recommanded Product: 53939-30-3

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

In 2018,Dyes and Pigments included an article by Yan, Zhengquan; Wei, Gang; Guang, Shanyi; Xu, Manman; Ren, Xia; Wu, Rongliang; Zhao, Gang; Ke, Fuyou; Xu, Hongyao. Formula: C6H7Br2N. The article was titled 《A multidentate ligand chromophore with rhodamine-triazole-pyridine units and its acting mechanism for dual-mode visual sensing trace Sn2+》. The information in the text is summarized as follows:

A multidentate ligand chromophore, combining rhodamine, triazole, and pyridine units, was identified and developed for the 1st time. Using triazole and pyridine rings as coordinating functional recognition groups, it was expected to selectively recognize Sn2+ to form some stable 5-member or 6-member rings with nitrogen and oxygen atoms. Under the optimized conditions, the ligand chromophore could selectively react with trace Sn2+ in CH3CN/H2O (99/1, volume/volume), accompanying with obvious changes in fluorescent spectrum, UV-visible spectrum and visual color. For fluorescent anal., a turn-on fluorescence at 587 nm was found and increased linearly at 1.2-6.2 × 10-7 mol L-1 Sn2+ from colorless to orange. For UV-visible one, a new absorption peak at 560 nm emerged with a linear range of 2.0-11.0 × 10-7 mol L-1 Sn2+ from colorless to pink. The action mechanism between the ligand chromophore and Sn2+ was confirmed basing on UV-visible titration, 1H NMR titration, Job’s plot, binding constants and theor. calculation In addition to this study using 2-(Bromomethyl)pyridine hydrobromide, there are many other studies that have used 2-(Bromomethyl)pyridine hydrobromide(cas: 31106-82-8Formula: C6H7Br2N) was used in this study.

2-(Bromomethyl)pyridine hydrobromide(cas: 31106-82-8) belongs to pyridine. When pyridine is adsorbed on oxide surfaces or in porous materials, the following species are commonly observed: (i) pyridine coordinated to Lewis acid sites, (ii) pyridine H-bonded to weakly acidic hydroxyls, and (iii) protonated pyridine. At high coverage, physisorbed pyridine and protonated dimers can also be observed.Formula: C6H7Br2N

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

In 2019,ChemSusChem included an article by Gholinejad, Mohammad; Oftadeh, Erfan; Shojafar, Mohammad; Sansano, Jose M.; Lipshutz, Bruce H.. Synthetic Route of C6H7Br2N. The article was titled 《Synergistic Effects of ppm Levels of Palladium on Natural Clinochlore for Reduction of Nitroarenes》. The information in the text is summarized as follows:

The modified naturally occurring clay clinochlore with ppm amounts of palladium that leads to a new and very effective reagent for the reduction of numerous aromatic nitro species RNO2 (R = H3CC(O)NHC6H4, naphthalen-1-yl, pyridin-2-yl, etc.) has been augmented. When palladium nanoparticles are supported on pyridyltriazole-modified clinochlore, iron within clinochlore acts synergistically with palladium to catalyze the reduction of a wide variety of nitroarenes at room temperature in aqueous media. Based on E-factor calculations, the catalyst system is found to be in line with green chem. standards and can be recycled up to five times. In the experiment, the researchers used 2-(Bromomethyl)pyridine hydrobromide(cas: 31106-82-8Synthetic Route of C6H7Br2N)

2-(Bromomethyl)pyridine hydrobromide(cas: 31106-82-8) 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.Synthetic Route of C6H7Br2N

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

In 2019,Organic Letters included an article by Cheng, Yuan-Yuan; Lei, Tao; Su, Longlong; Fan, Xiuwei; Chen, Bin; Tung, Chen-Ho; Wu, Li-Zhu. Safety of fac-Tris(2-phenylpyridine)iridium. The article was titled 《Visible Light Irradiation of Acyl Oxime Esters and Styrenes Efficiently Constructs β-Carbonyl Imides by a Scission and Four-Component Reassembly Process》. The information in the text is summarized as follows:

Acyl radical triggered difunctionalizations of aryl olefins have been realized using oxime ester as the acyl precursor for the first time. Irradiation of fac-Ir(ppy)3 and oxime ester by visible light caused scission into three components, which recombined with olefins to yield significant β-carbonyl imides, e.g., I showing good functional group tolerance and high atom economy. Control experiments as well as spectroscopic and electrochem. studies revealed the efficient intermol. reorganization of oxime ester into styrene with the aid of solvent exchange. After reading the article, we found that the author used fac-Tris(2-phenylpyridine)iridium(cas: 94928-86-6Safety of fac-Tris(2-phenylpyridine)iridium)

fac-Tris(2-phenylpyridine)iridium(cas: 94928-86-6) belongs to pyridine. Pyridines are often used as catalysts or reagents; particular notice has been paid recently to how pyridine coordinates to metal centers enabling a wide range of valuable reactions. Safety of fac-Tris(2-phenylpyridine)iridium

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

The author of 《Mitochondria-localized iridium(III) complexes with anthraquinone groups as effective photosensitizers for photodynamic therapy under hypoxia》 were Guo, Song; Han, Meiping; Chen, Ruizhe; Zhuang, Yanling; Zou, Liang; Liu, Shujuan; Huang, Wei; Zhao, Qiang. And the article was published in Science China: Chemistry in 2019. Electric Literature of C5H3Br2N The author mentioned the following in the article:

Photodynamic therapy (PDT) is a potential way for the tumor treatment. However, it notably suffers the limitation of hypoxia in solid tumors. Thus, it is significant to develop effective photosensitizers which can exhibit excellent therapeutic performance under both normoxia and hypoxia. Herein, we reported four ionic iridium(III) complexes (Ir1-Ir4) with anthraquinone groups which can regulate their excited state energy levels effectively. Among them, the energy gap of Ir1 was between 1.63 and 2.21 eV, which can match well with that of O2, and the HOMO energy of Ir1 is less than -5.51 eV. Compared with Ir2-Ir4, the luminescent quantum efficiency of Ir1 was the highest. Particularly, Ir1 can specifically target the mitochondria of the tumor cells. Meanwhile, Ir1 showed high singlet oxygen quantum yields (φΔ) in both solutions and living cells with low cytotoxicity. The results of PDT experiments revealed that Ir1, as a photosensitizer, exhibited excellent therapeutic effect not only in normoxia but also in hypoxia condition. We believe that this work is meaningful for developing excellent PDT agents based on cyclometalated Ir(III) complexes via rational ligand modification. In the experiment, the researchers used many compounds, for example, 2,5-Dibromopyridine(cas: 624-28-2Electric Literature of C5H3Br2N)

2,5-Dibromopyridine(cas: 624-28-2) 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.Electric Literature of C5H3Br2N

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

The author of 《Efficient Passivation with Lead Pyridine-2-Carboxylic for High-Performance and Stable Perovskite Solar Cells》 were Fu, Sheng; Li, Xiaodong; Wan, Li; Wu, Yulei; Zhang, Wenxiao; Wang, Yueming; Bao, Qinye; Fang, Junfeng. And the article was published in Advanced Energy Materials in 2019. Product Details of 98-98-6 The author mentioned the following in the article:

Stability has become the main obstacle for the commercialization of perovskite solar cells (PSCs) despite the impressive power conversion efficiency (PCE). Poor crystallization and ion migration of perovskite are the major origins of its degradation under working condition. Here, high-performance PSCs incorporated with pyridine-2-carboxylic lead salt (PbPyA2) are fabricated. The pyridine and carboxyl groups on PbPyA2 can not only control crystallization but also passivate grain boundaries (GBs), which result in the high-quality perovskite film with larger grains and fewer defects. In addition, the strong interaction among the hydrophobic PbPyA2 mols. and perovskite GBs acts as barriers to ion migration and component volatilization when exposed to external stresses. Consequently, superior optoelectronic perovskite films with improved thermal and moisture stability are obtained. The resulting device shows a champion efficiency of 19.96% with negligible hysteresis. Furthermore, thermal (90°C) and moisture (RH 40-60%) stability are improved threefold, maintaining 80% of initial efficiency after aging for 480 h. More importantly, the doped device exhibits extraordinary improvement of operational stability and remains 93% of initial efficiency under maximum power point (MPP) tracking for 540 h. The experimental part of the paper was very detailed, including the reaction process of Picolinic acid(cas: 98-98-6Product Details of 98-98-6)

Picolinic acid(cas: 98-98-6) is used in the preparation of 2-Aminodihydro[1,3]thiazines as BACE 2 inhibitors and their preparation and use in the treatment of diabetes.Product Details of 98-98-6

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem