42839-04-3Relevant articles and documents
Electron-deficient heteroarenium salts: An organocatalytic tool for activation of hydrogen peroxide in oxidations
?turala, Ji?í,Bohá?ová, Soňa,Chudoba, Josef,Metelková, Radka,Cibulka, Radek
, p. 2676 - 2699 (2015/03/18)
A series of monosubstituted pyrimidinium and pyrazinium triflates and 3,5-disubstituted pyridinium triflates were prepared and tested as simple catalysts of oxidations with hydrogen peroxide, using sulfoxidation as a model reaction. Their catalytic efficiency strongly depends on the type of substituent and is remarkable for derivatives with an electron-withdrawing group, showing reactivity comparable to that of flavinium salts which are the prominent organocatalysts for oxygenations. Because of their high stability and good accessibility, 4-(trifluoromethyl)pyrimidinium and 3,5-dinitropyridinium triflates are the catalysts of choice and were shown to catalyze oxidation of aliphatic and aromatic sulfides to sulfoxides, giving quantitative conversions, high preparative yields and excellent chemoselectivity. The high efficiency of electron-poor heteroarenium salts is rationalized by their ability to readily form adducts with nucleophiles, as documented by low pKR+ values (pKR+ red > -0.5 V). Hydrogen peroxide adducts formed in situ during catalytic oxidation act as substrate oxidizing agents. The Gibbs free energies of oxygen transfer from these heterocyclic hydroperoxides to thioanisole, obtained by calculations at the B3LYP/6-311++g(d,p) level, showed that they are much stronger oxidizing agents than alkyl hydroperoxides and in some cases are almost comparable to derivatives of flavin hydroperoxide acting as oxidizing agents in monooxygenases.
TETRAHYDROISOQUINOLIN-2-YL-(QUINAZOLIN-4-YL) METHANONE COMPOUNDS AS CANCER CELL GROWTH INHIBITORS
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Page/Page column 32-33, (2014/09/29)
Tetrahydroisoquinolin-2-yl-(quinazolin-4-yl)methanone derivatives represented by formula (I), pharmacologically acceptable salts thereof, and compositions containing such compounds are described. Methods for treating hyperproliferative disorders by administering the compounds are also described. 1,2,3,4-tetrahydroisoquinoline derivatives for making tetrahydroisoquinolin-2-yl-(quinazolin-4-yl)methanone compounds are also described.
CYCLOBUTENEDIONE DERIVATIVES
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Page/Page column 65, (2010/12/17)
The present invention relates to compounds of the formula (I): to pharmaceutically acceptable salts therefore and to pharmaceutically acceptable solvates of said compounds and salts, wherein the substituents are defined herein; to compositions containing such compounds; and to the uses of such compounds in the treatment of various diseases, particularly inflammatory conditions.
Substituent Effects on Photochemical Hydrogen Abstraction in 2-Acylpyridines, 2-Acylpyrazines, and 4-Acylpyrimidines
Rao, C. Janakiram,Agosta, William C.
, p. 2125 - 2131 (2007/10/02)
Stern-Volmer quenching of the photochemistry of 1c indicates that N- and O-abstraction (eqs 1 and 2, respectively) are quenched at different rates (Figure 1).For quenching of 2c kqτ is 157 M-1 and for 3c, 64 M-1.When 1c is sensitized with triplet sensitizers of increasing ET,N-abstraction increases (Table 1).These data indicate that N- and O-abstraction in 1c take place from distiguishable triplet states.Survey of Φp's of ring-substituted ketones 1b-d, 6d, 7a,b,d, 8b, 9b,d, 10b, and 11d demonstartes the effect of substitution on the competition between N- and O-abstraction (Table 2).For methyl- and dicyano-substituted ketones, the results can be understood simply in terms of shifts in ET of the n?* and ??* states of the heterocycle.The photochemistry of all these ketones requires consideration of interactions among three triplet states.
PYRIMIDINES. 73. SYNTHESIS OF ACETYLPYRIMIDINES
Naumenko, I. I.,Mikhaleva, M. A.,Mamaev, V. P.
, p. 710 - 714 (2007/10/02)
It is shown that the use of benzene as the solvent in the preparation of 2- and 4-acetylpyrimidines from cyanopyrimidines via the Grignard reaction makes this reaction a practical method for the preparation of pyrimidinyl ketones.Preparatively convenient methods for the preparation of 4-acetylpyrimidine from 4-ethylpyrimidine through the α-oximino derivative and 5-acetylpyrimidine from 4,6-dichloro derivatives of pyrimidine are proposed.
