- Splitting a Substrate into Three Parts: Gold-Catalyzed Nitrogenation of Alkynes by C-C and C≡C Bond Cleavage
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A gold-catalyzed nitrogenation of alkynes for the synthesis of carbamides and amino tetrazoles through C-C and C≡C bond cleavages is described. A diverse set of functionalized carbamide and amino tetrazole derivatives were selectively constructed under mild conditions. The chemoselectivity can be easily switched by the selection of the acid additives. The reaction is characterized by its broad substrate scope, direct construction of high value products, easy operation under air, and mild conditions at room temperature. This chemistry provides a way to transform alkynes by splitting the substrate into three parts.
- Qin, Chong,Su, Yijin,Shen, Tao,Shi, Xiaodong,Jiao, Ning
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p. 350 - 354
(2016/01/25)
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- 1-arylpyrimidine derivatives and pharmaceutical use thereof
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The present invention relates to 1-arylpyrimidine derivatives represented by general formula (I): STR1 wherein R1 is H, alkyl or aralkyl; Ar is 1-naphthyl, or a substituted or unsubstituted phenyl group; R4 is a substituted phenyl, a substituted styryl, 1-methylcyclohexyl, 4-methylcyclohexyl, 4-oxo-4H-pyran-2-yl or 2-oxo-2H-pyran-5-yl group; R5 and R6 are each independently H or alkyl; R3 is H, and R7 and R8 are combined together to be oxo, or else R3 and R7 are combined together to be another direct bond, and R5 and R8 are combined together to be a direct bond, or pharmaceutically acceptable salts thereof; and methods for treating allergic diseases with such compounds.
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- PREPARATION AND PROPERTIES OF 3-ALKYL-i-ARYLNITROSOUREAS AND RELATED COMPOUNDS
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Nitrosation of 3-alkyl-1-arylureas was investigated with sodium nitrite in 99percent formic acid or with isoamyl nitrite in chloroform.The preparation of 3-alkyl-1-aryl-1-nitrosoureas was effectively performed by using isoamyl nitrite in the absence of acids, since the 1-nitrosoureas were isomerized to the 3-nitroso isomers by acids.The carbon-13 nuclear magnetic resonance and infrared spectral properties of the products were examined and their structural features are discussed.It was found that 3-alkyl-1-aryl-1-nitrosoureas decomposed to form alkyl isocyanates and 3-alkyl-1-(2-nitroaryl)ureas in carbon tetrachloride. 1,3-Rearrangement and transnitrosation also took place in this solvent.Keywords - 3-alkyl-1-arylnitrosourea; 3,3-diethyl-1-tolyl-1-nitrosourea; N-nitrosourea; nitrosation; 1,3-rearrangement; isomerization; transnitrosation; nitration
- Tanno, Masayuki,Sueyoshi, Shoko
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p. 1360 - 1371
(2007/10/02)
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