Novel generation of azomethine imines from α-silylnitrosamines by 1,4-silatropic shift and their cycloaddition
摘要:
Novel and facile generation of azomethine imines from alpha-silylnitrosamines and subsequent cycloaddition with dipolarophiles leading to a variety of pyrazole derivatives have been developed. The key to the reaction is a 1,4-silatropic shift caused by strong affinity of the nitroso oxygen atom toward the silicon atom. Thus, alpha-silylnitrosamines are treated with 1 equiv. of dipolarophiles in refluxing toluene for 1 h to give pyrazole derivatives in good to excellent yields. (C) 1999 Elsevier Science Ltd. All rights reserved.
Reaction of 2-dimethylaminomethylene-1,3-diones with dinucleophiles. VI. Synthesis of ethyl or methyl 1,5-disubstituted 1<i>H</i>-pyrazole-4-carboxylates
作者:Giulia Menozzi、Luisa Mosti、Pietro Schenone
DOI:10.1002/jhet.5570240634
日期:1987.11
Reaction of ethyl or methyl 3-oxoalkanoates with N,N-dimethylformamide dimethyl acetal gave, generally in excellent yields, a series of ethyl or methyl 2-dimethylaminomethylene-3-oxoalkanoates II which reacted with phenylhydrazine to afford the esters of 5-substituted 1-phenyl-1H-pyrazole-4-carboxylic acids III in high yields. Esters III were hydrolyzed to the relative 5-substituted 1-phenyl-1H-pyrazole-4-carboxylic
Nitropyrimidinone 1 revealed new reactivity upon treatment with active methylene compounds 2 under basic conditions. The N1-C2-C3-C4 moiety of 1 combined with two carbon units of 2 affording polyfunctionalized pyridones 4, which was hitherto unknown ring transformation. On the other hand, the N1-C2 moiety of 1 was transferred to the methylene group of 2 giving functionalized enamines 3. It was also
Synthesis, characterization and antimicrobial activity of novel ethyl 1-(N-substituted)-5-phenyl-1H-pyrazole-4-carboxylate derivatives
作者:B. Chandrakantha、Arun M. Isloor、Prakash Shetty、Shrikrishna Isloor、Shridhar Malladi、Hoong Kun Fun
DOI:10.1007/s00044-011-9796-9
日期:2012.9
antibacterial properties against Staphylococcus aureus, Bacillus subtilis, Escherichia coli , and Pseudomonas aeruginosa . Among the screened samples, 3c , 3f , 3k, and 3l have showed excellent antibacterial activity against all the tested bacterial strains as compared to the standard drug Ceftriaxone. Few of the compounds were found to be biologically potent. Molecular structure of compound 3i was confirmed by
PYRAZOLOPYRIMIDINE JAK INHIBITOR COMPOUNDS AND METHODS
申请人:Gibbons Paul
公开号:US20120190665A1
公开(公告)日:2012-07-26
A compound of Formula I, enantiomers, diasteriomers, tautomers or pharmaceutically acceptable salts thereof, wherein R
1
, R
2
and R
3
are defined herein, are useful as inhibitors of one or more Janus kinases. A pharmaceutical composition that includes a compound of Formula I and a pharmaceutically acceptable carrier, adjuvant or vehicle, and methods of treating or lessening the severity of a disease or condition responsive to the inhibition of a Janus kinase activity in a patient are disclosed.