Highly efficient method for the preparation of N-tert-butylamides by reaction of nitriles with tert-butylacetate is described using Amberlyst-15 as a recyclable heterogeneous catalyst.Selective amidation of benzonitri...Highly efficient method for the preparation of N-tert-butylamides by reaction of nitriles with tert-butylacetate is described using Amberlyst-15 as a recyclable heterogeneous catalyst.Selective amidation of benzonitrile in the presence of acetonitrile was also achieved.展开更多
We analyzed statistically the linear correlation of the solvatochromic shifts of the stilbazolium-like dyes in the nonselected solvents with the reaction field function, L(?T) — bL(n2), and the solvent polarity param...We analyzed statistically the linear correlation of the solvatochromic shifts of the stilbazolium-like dyes in the nonselected solvents with the reaction field function, L(?T) — bL(n2), and the solvent polarity parameter, ENT respectively, and observed that there were not perfectly linearity relationships between them, so we introduced ENT into L(?T) — bL( n2) to form a new reaction field function, L(?T) — bL(n2) + g ENT called as me modified reaction field function, which can be perfectly linearly correlated with the solvatochromic shifts of the stilbazolium-like dyes in the nonselected solvents.展开更多
The total syntheses of 8-oxyberberine and oxohomoberberines were accomplished starting from commercially available 5-bromobenzo[d][1,3]dioxole,piperonal and sesamol in high total yield.The key steps involved a modifie...The total syntheses of 8-oxyberberine and oxohomoberberines were accomplished starting from commercially available 5-bromobenzo[d][1,3]dioxole,piperonal and sesamol in high total yield.The key steps involved a modified Pomeranz-Fritsch reaction and the intramolecular Heck cyclization.This approach is short,convenient and suitable for the preparation of homoberberine analogues.展开更多
The results of studying inhibitory effect of streptomycin on the modified Berthelot reaction were presented in this paper and a new kinetic method for determining streptomycin in pharmaceutical preparations and human ...The results of studying inhibitory effect of streptomycin on the modified Berthelot reaction were presented in this paper and a new kinetic method for determining streptomycin in pharmaceutical preparations and human urine was developed on the basis of the obtained results. The rates of catalytic and catalytic-inhibitory reaction were monitored at 700 nm （t=25 ±0.1 ℃） using UV/vis spectrophotometer. By analyzing the spectra and experimental dependences of the catalytic and catalytic-inhibitory reaction rates on the reactant concentrations, it was noticed that streptomycin attacked nitroprusside and hypochlorite causing the inhibition of the production of 2,2＇-dicarboxylindophenol. According to this effect, an analytical decrease for determination of urea by modified Berthelot reaction appeared in the presence of small amounts of streptomycin. Beer＇s law was obeyed in the interval of streptomycin sulfate concentration from 18.2 to 182 μg·mL^-1. The detection limit calculated by two methods was obtained at 11.75 μg·mL^-1 and 8.54 μg·mL^-1. The relative standard deviation of 0.55%--8.83% and the recovery of 109.10% were determined. The obtained results were validated using the referent HPLC method.展开更多
基金Islamic Azad University of Rasht Branch for financial assistance
文摘Highly efficient method for the preparation of N-tert-butylamides by reaction of nitriles with tert-butylacetate is described using Amberlyst-15 as a recyclable heterogeneous catalyst.Selective amidation of benzonitrile in the presence of acetonitrile was also achieved.
基金Project supported by the National Natural Science Foundation of China (No. 29682001 and 29832030).
文摘We analyzed statistically the linear correlation of the solvatochromic shifts of the stilbazolium-like dyes in the nonselected solvents with the reaction field function, L(?T) — bL(n2), and the solvent polarity parameter, ENT respectively, and observed that there were not perfectly linearity relationships between them, so we introduced ENT into L(?T) — bL( n2) to form a new reaction field function, L(?T) — bL(n2) + g ENT called as me modified reaction field function, which can be perfectly linearly correlated with the solvatochromic shifts of the stilbazolium-like dyes in the nonselected solvents.
基金This work was supported by the National Natural Science Foundation of China(No.81373259).
文摘The total syntheses of 8-oxyberberine and oxohomoberberines were accomplished starting from commercially available 5-bromobenzo[d][1,3]dioxole,piperonal and sesamol in high total yield.The key steps involved a modified Pomeranz-Fritsch reaction and the intramolecular Heck cyclization.This approach is short,convenient and suitable for the preparation of homoberberine analogues.
文摘The results of studying inhibitory effect of streptomycin on the modified Berthelot reaction were presented in this paper and a new kinetic method for determining streptomycin in pharmaceutical preparations and human urine was developed on the basis of the obtained results. The rates of catalytic and catalytic-inhibitory reaction were monitored at 700 nm （t=25 ±0.1 ℃） using UV/vis spectrophotometer. By analyzing the spectra and experimental dependences of the catalytic and catalytic-inhibitory reaction rates on the reactant concentrations, it was noticed that streptomycin attacked nitroprusside and hypochlorite causing the inhibition of the production of 2,2＇-dicarboxylindophenol. According to this effect, an analytical decrease for determination of urea by modified Berthelot reaction appeared in the presence of small amounts of streptomycin. Beer＇s law was obeyed in the interval of streptomycin sulfate concentration from 18.2 to 182 μg·mL^-1. The detection limit calculated by two methods was obtained at 11.75 μg·mL^-1 and 8.54 μg·mL^-1. The relative standard deviation of 0.55%--8.83% and the recovery of 109.10% were determined. The obtained results were validated using the referent HPLC method.
