40061-45-8Relevant academic research and scientific papers
Palladium-Catalyzed Direct α-C(sp3) Heteroarylation of Ketones under Microwave Irradiation
Quillen, Andrew,Nguyen, Quynh,Neiser, Matthew,Lindsay, Kara,Rosen, Alexander,Ramirez, Stephen,Costan, Stefana,Johnson, Nathan,Do, Thuy Donna,Rodriguez, Oscar,Rivera, Diego,Atesin, Abdurrahman,Ate?in, Tülay Aygan,Ma, Lili
, p. 7652 - 7663 (2019/05/22)
Heteroaryl compounds are valuable building blocks in medicinal chemistry and chemical industry. A palladium-catalyzed direct α-C(sp3) heteroarylation of ketones under microwave irradiation is developed and reported in this study. Under optimized condition
Tandem Pd-Catalyzed Intermolecular Allylic Alkylation/Allylic Dearomatization Reaction of Benzoylmethyl pyridines, Pyrazines, and Quinolines
Zhang, Hui-Jun,Yang, Ze-Peng,Gu, Qing,You, Shu-Li
supporting information, (2019/05/08)
An efficient synthesis of nitrogen-containing heterocycles via Pd-catalyzed tandem allylic alkylation and dearomatization reactions was reported. In this reaction design, heteroarenes such as pyridines, pyrazines, and quinolines serve as bis-nucleophiles by installing a benzoyl group at the C2 benzylic position. With but-2-ene-1,4-diyl dimethyl dicarbonate as the bis-electrophile, the tandem Pd-catalyzed intermolecular allylic alkylation/allylic dearomatization reaction of benzoylmethyl-substituted heteroarenes has been developed. 2,3-Dihydroindolizine, 6,7-dihydropyrrolo[1,2-a]pyrazine, and 1,2-dihydropyrrolo[1,2-a]quinolin derivatives were obtained in moderate to good yields.
NOVEL DIHYDROPYRIMIDIN-2(1H)-ONE COMPOUNDS AS S-NITROSOGLUTATHIONE REDUCTASE INHIBITORS
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Page/Page column 143, (2011/04/24)
The present invention is directed to novel dihydropyrimidin-2(1H)-one compounds useful as S-nitrosoglutathione reductase (GSNOR) inhibitors, pharmaceutical compositions comprising such compounds, and methods of making and using the same.
Process of preparing benzodiazepine compounds useful as antagonists of CCK or of gastrine
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, (2008/06/13)
A benzodiazepine derivative of formula I, or a pharmaceutically acceptable salt thereof: STR1 wherein: (a) R4 is an alkyl, cycloalkyl or aryl group. (b) R10 is chosen from halo, OH, CH3, OCH3, NR11 R12, NO2, NHCHO, CO2 H and CN, and R11 and R12 are independently selected from H and alkyl (C1 -C5) or together NR11 R12 form a cyclic structure II, STR2 wherein a is 1-6; and (c) R2 is an aromatic 5- or 6-membered, substituted or unsubstituted heterocycle containing at least two heteroatoms of which at least one is nitrogen. These compounds are gastrin and/or CCK-B receptor antagonists.
Keto-Enol Tautomerism of Phenacylpyrazine: Acid Catalysis with Protonation at Nitrogen
Carey, A. R. Edwin,O'Ferrall, Rory A. More,Murphy, Michael G.,Murray, Brian A.
, p. 2471 - 2480 (2007/10/02)
Kinetic and equilibrium measurements for ionisation and enolisation of 2-phenacylpyrazine in aqueous solution at 25 deg C yield a tautomeric constant pKE = 2.05 (where KE = /) and pKas for loss of a methylene proton and for protonation at nitrogen of 11.90 and 0.40, respectively.In contrast to 2-phenacylpyridine the low basicity of the pyrazine nitrogens renders an enaminone tautomer less stable than the enol and a value of pKM = 4.4 (KM = /) is estimated for this equilibrium.Evidence is presented that acid catalysis of keto-enol tautomerism occurs with protonation at the N-1 nitrogen atom rather than carbonyl group (or N-4 nitrogen) despite the proton being bound to oxygen in the enolic product.This preference reflects relative magnitudes of binding constants (1/Ka) and activating factors (PAF) for protonation at the different positions.Broensted and Marcus equations are used to express catalytic efficiency in terms of equilibrium constants for binding the catalyst to the reactant and products of the uncatalysed reaction.The form of catalysis observed, which reflects the influence of proton binding on the activation energy of the reaction, is contrasted with that in intramolecular or enzymatic reactions, which normally derives from approximation of the reactants and is entropic in origin.The significance of optimum binding of the catalyst to the transition state in the two cases is briefly compared.
TAUTOMERISM OF DERIVATIVES OF AZINES. 16. TAUTOMERISM OF ACYLMETHYLPYRAZINES AND -QUINOXALINES
Mainagashev, I. Ya.,Lapachev, V. V.,Fedotov, M. A.,Mamaev, V. P.
, p. 1339 - 1342 (2007/10/02)
The tautomeric equilibria of acylmethylpyrazines and -quinoxalines in chloroform were studied by 1H, 14N, and 17O NMR spectroscopy.It was shown that keto-enol tautomerism is realized in the acylmethylpyrazine series.Annelation leads to the development of an ylidene tautomer in the acylmethylquinoxaline series.A marked dependence of the position of the intrachelate equilibrium on the character of the solvent was observed.
SRN1 Mechanism in Heteroaromatic Nucleophilic Substitution. Reactions Involving Halogenated Pyrimidines, Pyridazines, and Pyrazines
Carver, David R.,Komin, Andrew P.,Hubbard, James S.,Wolfe, James S.
, p. 294 - 299 (2007/10/02)
Reactions of 2-chloropyrimidine (1), 4-chloro-2,6-dimethoxypyrimidine (7), 3-chloro-6-methoxypyridazine (9), and 2-chloropyrazine (14) with a representative series of ketone enolates in liquid ammonia exhibited characteristics consistent with a radical-chain (SRN1) mechanism for substituton.Diazines 1 and 9 showed an unexpected sensitivity to enolate ion structure, with 1 reacting best with tertiary enolates and 9 undergoing substitution most satisfactorily with primary enolates.The order of SRN1 reactivity among the various substrates was found to be 14 > 9 > 7 =ca. 1.Thus 1 and 7 required photostimulation at 35o nm for satisfactory displacemement of chloride, 9 underwent some substitution without illumination, and 14 reacted smoothly in the dark.
