18591-57-6Relevant academic research and scientific papers
Discrimination in the solid-state photodimerization of 1-methyl-5,6- diphenylpyrazin-2-one
Kaftory, Menahem,Shteiman, Vitaly,Lavy, Tali,Scheffer, John R.,Yang, Jie,Enkelmann, Volker
, p. 847 - 853 (2005)
1-Methyl- and 1-ethyl-5,6-diphenylpyrazin-2-one crystallize in two modifications, one of which is light-stable and the other light-sensitive. The light-sensitive modification is known to undergo photodimerization in the solid state. This polymorph crystallizes in the monoclinic space group P21 with two crystallographically independent molecules in the asymmetric unit. The molecules are packed in stacks running parallel to the unique b axis. The two independent molecules are arranged alternately along the stack. In principle, there are two different pairs of molecules within a stack that can undergo photodimerization, and each should form a different enantiomer. A large crystal was irradiated and a solution of the product was separated by HPLC. The optical purity of the (+)-enantiomer sample was estimated to be greater than 90%. This finding indicates that only one of the two pairs undergoes photoreaction. The structure of a single crystal of the pyrazinone was elucidated by X-ray diffractometry before and after irradiation with a laser at a wavelength of 488 nm to 19% conversion. The results of the crystal-structure determinations provide additional evidence that only one of the two pairs of molecules undergoes photodimerization although there are no significant differences between the distances between the reacting centers. Furthermore, the latter results suggest that weak hydrogen bonds are a dominant factor that determines which of the two pairs is dimerized upon irradiation. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
Synthesis method of diphenyl pyrazine derivative
-
Paragraph 0038-0042, (2021/06/13)
The invention discloses a synthesis method of a diphenyl pyrazine derivative. The method is characterized in that benzil and glycinamide are used as raw materials, and a target product is prepared through five-step reaction. The obtained target product is high in purity, subsequent production of high-quality drugs is facilitated, and the synthesis method is reasonable in route design, mild in reaction condition, free of high-temperature reaction, good in safety and high in feasibility.
C?H Methylation of Iminoamido Heterocycles with Sulfur Ylides**
Ghosh, Prithwish,Kwon, Na Yeon,Kim, Saegun,Han, Sangil,Lee, Suk Hun,An, Won,Mishra, Neeraj Kumar,Han, Soo Bong,Kim, In Su
supporting information, p. 191 - 196 (2020/10/29)
The direct methylation of N-heterocycles is an important transformation for the advancement of pharmaceuticals, agrochemicals, functional materials, and other chemical entities. Herein, the unprecedented C(sp2)-H methylation of iminoamido heterocycles as nucleoside base analogues is described. Notably, trimethylsulfoxonium salt was employed as a methylating agent under aqueous conditions. A wide substrate scope and excellent level of functional-group tolerance were attained. Moreover, this method can be readily applied to the site-selective methylation of azauracil nucleosides. The feasibility of gram-scale reactions and various transformations of the products highlight the synthetic potential of the developed method. Combined deuterium-labeling experiments aided the elucidation of a plausible reaction mechanism.
A preparation method of a diphenyl pyrazine compound
-
Paragraph 0049-0051; 0069-0072; 0089-0091; 0108-0110; 0127, (2018/10/27)
A diphenyl pyrazine compound I having a novel structure is developed according to structures of existing IP receptor agonists and a preparation method of the compound I is provided. The method is simple to operate and high in yield, and the yield of each step is higher than 70% preferably. The compound I can be efficiently prepared by the method. The invention also provides a preparation method ofan intermediate compound X for preparing the compound I, and the method has high yield and high product purity.
PROCESS FOR THE PREPARATION OF DIPHENYLPYRAZINE DERIVATIVES
-
Page/Page column 11-12, (2017/10/31)
The present invention relates to a process for the preparation of amorphous Selexipag from Selexipag crystalline salts using a solvent.
AN IMRPOVED PROCESS FOR THE PREPARATION OF SELEXIPAG OR ITS PHARMACEUTICALLY ACCEPTABLE SALTS
-
Page/Page column 11, (2017/08/01)
The present invention provides an improved process for Selexipag of formula (I) or its pharmaceutically acceptable salts.
3-(Piperidin-4-ylmethoxy)pyridine Containing Compounds Are Potent Inhibitors of Lysine Specific Demethylase 1
Wu, Fangrui,Zhou, Chao,Yao, Yuan,Wei, Liping,Feng, Zizhen,Deng, Lisheng,Song, Yongcheng
supporting information, p. 253 - 263 (2016/01/29)
Methylation of histone lysine residues plays important roles in gene expression regulation as well as cancer initiation. Lysine specific demethylase 1 (LSD1) is responsible for maintaining balanced methylation levels at histone H3 lysine 4 (H3K4). LSD1 is a drug target for certain cancers, due to important functions of methylated H3K4 or LSD1 overexpression. We report the design, synthesis, and structure-activity relationships of 3-(piperidin-4-ylmethoxy)pyridine containing compounds as potent LSD1 inhibitors with Ki values as low as 29 nM. These compounds exhibited high selectivity (>160×) against related monoamine oxidase A and B. Enzyme kinetics and docking studies suggested they are competitive inhibitors against a dimethylated H3K4 substrate and provided a possible binding mode. The potent LSD1 inhibitors can increase cellular H3K4 methylation and strongly inhibit proliferation of several leukemia and solid tumor cells with EC50 values as low as 280 nM, while they had negligible effects on normal cells.
Synthesis Method of Organometallic Complex, Synthesis Method of Pyrazine Derivative, 5,6-Diaryl-2-Pyrazyl Triflate, Light-Emitting Element, Light-Emitting Device, Electronic Device, and Lighting Device
-
Paragraph 0173-0175, (2016/05/24)
Provided is a 5,6-diaryl-2-pyrazyl triflate, its synthetic method, and a method for synthesizing an organometallic complex having a triarylpyrazine ligand from the 5,6-diaryl-2-pyrazyl triflate. The triflate is readily obtained from the corresponding 5,6-diarylpyrazin-2-ol, and the palladium-catalyzed coupling of the 5,6-diaryl-2-pyrazyl triflate with an arylboronic acid derivative leads to a high yield of a triarylpyrazine derivative having high purity. The use of the triarylpyrazine derivative in the reaction with a metal compound such as a metal chloride results in an ortho-metallated organometallic complex with high purity. The high purity of the organometallic complex contributes to the extremely high durability of a light-emitting element.
Synthesis Method of Organometallic Complex, Synthesis Method of Pyrazine Derivative, 5,6-Diaryl-2-Pyrazyl Triflate, Light-Emitting Element, Light-Emitting Device, Electronic Device, and Lighting Device
-
Page/Page column, (2015/06/03)
Provided is a 5,6-diaryl-2-pyrazyl triflate, its synthetic method, and a method for synthesizing an organometallic complex having a triarylpyrazine ligand from the 5,6-diaryl-2-pyrazyl triflate. The triflate is readily obtained from the corresponding 5,6-diarylpyrazin-2-ol, and the palladium-catalyzed coupling of the 5,6-diaryl-2-pyrazyl triflate with an arylboronic acid derivative leads to a high yield of a triarylpyrazine derivative having high purity. The use of the triarylpyrazine derivative in the reaction with a metal compound such as a metal chloride results in an ortho-metallated organometallic complex with high purity. The high purity of the organometallic complex contributes to the extremely high durability of a light-emitting element.
Palladium(II)-catalyzed oxidative arylation of quinoxalin-2(1 H)-ones with arylboronic acids
Carrer, Amandine,Brion, Jean-Daniel,Messaoudi, Samir,Alami, Mouad
supporting information, p. 5606 - 5609 (2013/11/19)
A straightforward palladium-catalyzed oxidative C-3 arylation of quinoxalin-2(1H)-ones with arylboronic acids is reported. This protocol is compatible with a wide range of functional groups and allows construction of various biologically important quinoxalin-2(1H)-one backbones.
