Synthesis and anticonvulsant activity of enaminones. 2. Further structure-activity correlations
作者:K. R. Scott、Ivan O. Edafiogho、Erica L. Richardson、Vida A. Farrar、Jacqueline A. Moore、Elizabeth I. Tietz、Christine N. Hinko、Hyejung Chang、Afif El-Assadi、Jesse M. Nicholson
DOI:10.1021/jm00066a003
日期:1993.7
shown to be safer alternatives, the most notable was methyl 4-[(p-bromophenyl)amino]-6-methyl-2-oxocyclohex-3-en-1-oate, 13. Compound 13 had an ip ED50 of 4 mg/kg in the rat and a TD50 of 269 mg/kg, providing a protective index (TD50/ED50) of > 67. By variation in the ring size, additional aromatic substitutions and the synthesis of acyclic analogs, these newer compounds provide a more definitive insight
Deuterium Isotope Effects on 13C Chemical Shifts of Enaminones.
作者:Donka Kh. Zheglova、Daniel G. Genov、Simon Bolvig、Poul Erik Hansen、M. Hanfland、E. Dooryhee
DOI:10.3891/acta.chem.scand.51-1016
日期:——
Deuterium isotope effects on C-13 chemical shifts have been studied in a series of substituted N-alkyl and N-phenyl keto-enamines. The intramolecularly hydrogen bonded Z-forms show the largest two-bond isotope effects, (2) Delta C-1(ND). Methyl-substitution al C-l leads to a larger two-bond isotope effect in the N-phenyl-substituted derivatives. This effect is ascribed to steric compression. Space-filling substituents at the ortho-position of the N-phenyl ring lead to a decrease of the two-bond isotope effect. A correlation is found between (2) Delta C-1(ND) and (3) Delta C-2'(ND). The latter becomes negative in the sterically hindered cases. (3) Delta C-2'(ND) may therefore be used as a gauge of the twist of the phenyl ring.o-Hydroxy substitution of the CO-phenyl rings enables intramolecular hydrogen bonding to the carbonyl group. This kind of hydrogen bond with two donors to one acceptor leads to smaller (2) Delta C-2(ND) and (2) Delta C-2 ''(OD) isotope effects equivalent to weaker hydrogen bonds for the Z-isomer. This is ascribed to competition for the acceptor. For the E-isomer (2) Delta C(OD) is enhanced. The same feature is seen for N,N-dimethylamino enamines. This increase is ascribed to delocalization of the nitrogen lone-pair onto the carbonyl oxygen, thereby strengthening the hydrogen bond and thus leading to larger two-bond, (2) Delta C(OD), isotope effects.
KOZLOV, N. S.;PAK, V. D.;BURYLOVA, L. V.;GARTMAN, G. A., DOKL. AN BSSR, 33,(1989) N2, S. 1097-1100
作者:KOZLOV, N. S.、PAK, V. D.、BURYLOVA, L. V.、GARTMAN, G. A.
DOI:——
日期:——
General, Mild and Efficient Synthesis of β-Enaminones Catalyzed by Ceric Ammonium Nitrate
Ceric ammonium nitrate catalyzes the reaction between aromatic or aliphatic primary amines and a variety of β-dicarbonyl compounds, including β-ketoesters, β-ketothioesters and β-diketones. The reaction proceeds smoothly at room temperature in short reaction times and gives β-enaminones in good to excellent yields.