dihydropyrimidinones derivatives were synthesized in high yields by one pot three component Biginelli condensation from aldehyde, β keto ester and urea in ethanol,while cobalt chloride hexahydrate was used as a catal...dihydropyrimidinones derivatives were synthesized in high yields by one pot three component Biginelli condensation from aldehyde, β keto ester and urea in ethanol,while cobalt chloride hexahydrate was used as a catalyst.This modified Biginellis reaction not only makes the reaction period short,the operation simple,but also gives high yields.展开更多
Three water-soluble β-alanine C 60 adducts with different addition numbers, C 60(NHCH 2CH 2COONa) nH n(n=1,5,9), were synthesized. The products were characterized by FTIR, 1H NMR and elemental analysis. The antioxida...Three water-soluble β-alanine C 60 adducts with different addition numbers, C 60(NHCH 2CH 2COONa) nH n(n=1,5,9), were synthesized. The products were characterized by FTIR, 1H NMR and elemental analysis. The antioxidant activity of these C 60 adducts as the quencher for superoxide anion radical O -· 2 was evaluated by chemiluminescence in the system of pyrogallol-luminol. The results indicate that the three C 60 derivatives are all excellent quencher for superoxide anion radical O -· 2. The concentrations of 50% inhibition are 252, 140, 112 μmol/L respectively. This high efficiency should be attributed to many factors such as the numbers of remaining double bonds, donor effect of amino group and steric effect. However, the above results also suggest the effect of the adducted β-alanine groups is predominated in this system.展开更多
文摘dihydropyrimidinones derivatives were synthesized in high yields by one pot three component Biginelli condensation from aldehyde, β keto ester and urea in ethanol,while cobalt chloride hexahydrate was used as a catalyst.This modified Biginellis reaction not only makes the reaction period short,the operation simple,but also gives high yields.
文摘Three water-soluble β-alanine C 60 adducts with different addition numbers, C 60(NHCH 2CH 2COONa) nH n(n=1,5,9), were synthesized. The products were characterized by FTIR, 1H NMR and elemental analysis. The antioxidant activity of these C 60 adducts as the quencher for superoxide anion radical O -· 2 was evaluated by chemiluminescence in the system of pyrogallol-luminol. The results indicate that the three C 60 derivatives are all excellent quencher for superoxide anion radical O -· 2. The concentrations of 50% inhibition are 252, 140, 112 μmol/L respectively. This high efficiency should be attributed to many factors such as the numbers of remaining double bonds, donor effect of amino group and steric effect. However, the above results also suggest the effect of the adducted β-alanine groups is predominated in this system.