Results 231 to 240 of about 172,292 (284)
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Journal of Organic Chemistry, 2016
A novel, efficient, and facile approach for the synthesis of structurally important pyrimidines has been successfully developed by Cu-catalyzed and 4-HO-TEMPO-mediated [3 + 3] annulation of commercially available amidines with saturated ketones.
Junchen Zhan +3 more
semanticscholar +1 more source
A novel, efficient, and facile approach for the synthesis of structurally important pyrimidines has been successfully developed by Cu-catalyzed and 4-HO-TEMPO-mediated [3 + 3] annulation of commercially available amidines with saturated ketones.
Junchen Zhan +3 more
semanticscholar +1 more source
Journal of Organic Chemistry, 2016
New I2-catalyzed multicomponent bicyclization reactions of β-ketonitriles with sulfonyl hydrazides have been established, providing a direct and metal-free access toward unreported pyrazolo[1,5-a]pyrimidin-4-ium sulfonates.
Jun Sun +5 more
semanticscholar +1 more source
New I2-catalyzed multicomponent bicyclization reactions of β-ketonitriles with sulfonyl hydrazides have been established, providing a direct and metal-free access toward unreported pyrazolo[1,5-a]pyrimidin-4-ium sulfonates.
Jun Sun +5 more
semanticscholar +1 more source
New Pyrimidine Pathway involved in the Biosynthesis of the Pyrimidine of Thiamine [PDF]
Nature, 1967 OUR, studies with mutants of Salmonella typhimurium LT2 have revealed that the pyrimidine moiety of thiamine is synthesized by a new biosynthetic route using intermediates from the purine biosynthetic pathway. Radioactive labelling has indicated that the conventional nucleic acid pyrimidine biosynthetic pathway is not used for biosynthesis of the ...
Peter C. Newell, R. G. Tucker
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Journal of the Iranian Chemical Society, 2019
Compound 1 condensed with benzaldehyde to produce styryl pyrimidine 2. Pyridopyrimidines 5, 8 and 10 resulted from [4 + 2] cycloaddition (condensation) of 1 with malononitrile, ethyl cyanoacetate and/or ethyl acetoacetate. Compound 1 was also concerted to pyridopyrimidine 14 through multistep reaction (hydrolysis, chlorination, isothiocyanate formation
Hamed Y. Moustafa +4 more
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Compound 1 condensed with benzaldehyde to produce styryl pyrimidine 2. Pyridopyrimidines 5, 8 and 10 resulted from [4 + 2] cycloaddition (condensation) of 1 with malononitrile, ethyl cyanoacetate and/or ethyl acetoacetate. Compound 1 was also concerted to pyridopyrimidine 14 through multistep reaction (hydrolysis, chlorination, isothiocyanate formation
Hamed Y. Moustafa +4 more
openaire +2 more sources
Journal of Medicinal Chemistry, 2016
Three series of substituted pyrimidines were designed and synthesized. All target compounds were screened for kinase inhibitory activities against PI3Kα, and most IC50 values were found within the nanomolar range. Compounds 5d and 5p displayed comparable
Jiquan Zhang +10 more
semanticscholar +1 more source
Three series of substituted pyrimidines were designed and synthesized. All target compounds were screened for kinase inhibitory activities against PI3Kα, and most IC50 values were found within the nanomolar range. Compounds 5d and 5p displayed comparable
Jiquan Zhang +10 more
semanticscholar +1 more source
1987
Nucleic acids are comprised of nitrogenous bases (purines and pyrimidines), pentose sugars (ribose and deoxyribose) and phosphate groups. Specific sequences of purines and pyrimidines encode the genetic information of cells and organisms.
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Nucleic acids are comprised of nitrogenous bases (purines and pyrimidines), pentose sugars (ribose and deoxyribose) and phosphate groups. Specific sequences of purines and pyrimidines encode the genetic information of cells and organisms.
openaire +2 more sources
Catalytic asymmetric hydrogenation of pyrimidines.
Angewandte Chemie, 2015The asymmetric hydrogenation of pyrimidines proceeded with high enantioselectivity (up to 99% ee) using an iridium catalyst composed of [IrCl(cod)]2, a ferrocene-containing chiral diphosphine ligand (Josiphos), iodine, and Yb(OTf)3 (cod = 1,5 ...
R. Kuwano +3 more
semanticscholar +1 more source
Carbon-Carbon Bond Cleavage Reaction: Synthesis of Multisubstituted Pyrazolo[1,5-a]pyrimidines.
Journal of Organic Chemistry, 2015A new carbon-carbon bond cleavage reaction was developed for the efficient synthesis of multisubstituted pyrazolo[1,5-a]pyrimidines. This base induced reaction of 1,3,5-trisubstituted pentane-1,5-diones and substituted pyrazoles afforded good yields of ...
Pallabi Saikia, S. Gogoi, R. Boruah
semanticscholar +1 more source
, 2015
In the present work, ZnFe2O4 nanopowder, as a highly efficient and heterogeneous catalyst, was prepared and fully characterized by IR, UV, XRD, EDX and SEM analysis. The nanocatalyst was employed as a highly stable and reusable catalyst for the synthesis
A. Khazaei +4 more
semanticscholar +1 more source
In the present work, ZnFe2O4 nanopowder, as a highly efficient and heterogeneous catalyst, was prepared and fully characterized by IR, UV, XRD, EDX and SEM analysis. The nanocatalyst was employed as a highly stable and reusable catalyst for the synthesis
A. Khazaei +4 more
semanticscholar +1 more source
Silver catalysed decarboxylative alkylation and acylation of pyrimidines in aqueous media.
Organic and biomolecular chemistry, 2015Decarboxylative alkylation or acylation reactions of simple pyrimidines have been developed in aqueous media. Using aliphatic carboxylic acids or 2-oxocarboxylic acids and pyrimidines as substrates and silver as the catalyst, the 4-substituted alkyl or ...
W. Mai +7 more
semanticscholar +1 more source