carried out for the synthesized compounds along with a series of N(2)-pyridyl tetrahydroindazoles. 1 The results of the in vitro antimicrobial screening studies revealed that compounds 13, 16 against Staphylococcus aureus, 11 against Escherichia coli, 10-12, 16 against Pseudomonas aeruginosa and 12 against Klebsiella pneumoniae recorded almost two-fold better activity compared to the standard drug used.
Synthesis and NMR spectral study of somet(3)-aryl-r(2),c(4)-bisethoxycarbonyl-t(5)-hydroxy-c(5)-methylcyclohexanones
作者:K. Pandiarajan、R. T. Sabapathy Mohan、R. Gomathi、G. Muthukumaran
DOI:10.1002/mrc.1568
日期:2005.5
Six t(3)‐aryl‐r(2),c(4)‐bisethoxycarbonyl‐t(5)‐hydroxy‐c(5)‐methylcyclohexanones (6–11) were synthesized by condensing ArCHO (Ar = Ph, p‐O2NC6H4, p‐CH3OC6H4, p‐ClC6H4, m‐O2NC6H4 and m‐C6H5O6H4) with ethyl acetoacetate in the presence of methylamine and their 1H and 13C NMR spectra were recorded. 1H–1H COSY and NOESY spectra were recorded for 6 and 7 and also HSQC and HMBC spectra for 6 and 8. Elemental
Novel tandem reactions of ethyl acetoacetate with aromatic aldehydes: product- and stereo-selective formation of highly functionalised cyclohexanones
作者:Murugesan Srinivasan、Subbu Perumal
DOI:10.1016/j.tet.2006.05.068
日期:2006.8
The five-component tandemreaction of ethyl acetoacetate with aromatic aldehydes in the presence of pyrrolidine affords t(3),t(5)-diaryl-t(4)-[(E)-3-aryl-2-propenonyl]-r(2)-ethoxycarbonylcyclohexanones stereoselectively in good yields presumably via a tandem Knoevenagel condensation–Michael addition–condensation via enamine-deethoxycarbonylation–Michael addition sequence. The same reactants in the
Investigation of condensation products of aldehydes with acetoacetic ester catalyzed by organic bases: absolute configuration determination by X-ray crystallography and tautomeric equilibria studies by NMR spectroscopy
them. Furthermore, keto–enol tautomericequilibriums of β -keto esters 3a – e have also been investigated using NMR spectroscopy. The results indicated that β -keto esters 3a – e exist as a mixture of keto and enol isomers in chloroform solutions when giving sufficient time at room temperature. The equilibriums were on the side of the keto tautomer with the ratio [enol]/[keto] ranging from 0.11 to 0.66