Synthesis of a series of novel aryl and heteroaryl fused 2,8-dioxabicyclo[3.3.1]nonanes (3) was accomplished by one pot, catalyst free reaction of 2-hydroxy chalcone (1) with 3-trifluoromethyl substituted pyrazolone (2) in xylene at reflux temperature. The role of the trifluoromethyl functional group in formation of 3 was confirmed by comparative studies with 3-methyl substituted pyrazolones (2c,d)
Asymmetric Synthesis of 3,4-Dihydrocoumarins Bearing an α,α-Disubstituted Amino Acid Moiety
作者:Joanna Hejmanowska、Anna Albrecht、Jakub Pięta、Łukasz Albrecht
DOI:10.1002/adsc.201500598
日期:2015.12.14
An organocatalytic approach for the stereoselective synthesis of 3,4-dihydrocoumarins with an α,α-disubstituted amino acid moiety incorporated is presented. The developed methodology is based on the cascade reaction between α-substituted azlactones and 2-hydroxychalcones. It is initiated by a chiral Brønsted base-catalyzed enantio- and diastereoselective Michael reaction followed by the azlactone ring
ZrCl<sub>4</sub>-Catalysed Synthesis of New 4-(2-hydroxyphenyl)Pyrazolo[3,4-b]Pyridine Derivatives
作者:Meilin Liu、Guodong Yin
DOI:10.3184/174751915x14296297811712
日期:2015.5
In the presence of a catalytic amount of zirconium(IV) chloride, an efficient synthesis of new 4-(2-hydroxyphenyl)pyrazolo[3,4-b]pyridines has been developed by the reaction 2-hydroxychalcones with 3-methyl-1-phenyl-1H-pyrazol-5-amine in refluxing ethanol. All these novel compounds have been characterised by 1H NMR, 13C NMR, HRMS, IR spectra and X-ray crystallographic analysis.
Aminopeptidase N is considered as a promising anti-tumor target due to its role in tumor invasion, metastasis and angiogenesis. In this report, a new series of pyrazoline-based derivatives were designed, synthesized and evaluated for biological activities. The structure–activity relationships of these pyrazoline-based derivatives were also discussed in detail. Among them, compound 2k, with 2,6-dichloro