The ring opening of β-sultam v/a an H2O-assisted ammonolysis process was studied by using Density Functional Theory（DFT） method at the B3LYP/6-31G level as a further step in the theoretical investigation of the amm...The ring opening of β-sultam v/a an H2O-assisted ammonolysis process was studied by using Density Functional Theory（DFT） method at the B3LYP/6-31G level as a further step in the theoretical investigation of the ammonolysis reaction of β-sultams. The calculated pathways are analogous to those previously described for the non-assisted ammonolysis reaction. Solvent effects were assessed by using the polarized continuum model（PCM） method. The results show that mode 1 and pathway a in channel Ⅱ are the most favorable ones in both the cases. The energy barrier of the cleavage of C-S bonds producing P1 is the highest among all the energy barriers. The presence of a solvent in the continuum model disfavors the reaction, whereas the participation of water in the ammonolysis reaction plays a positive role and reduces the active energy greatly. The relative energies of all the transition states in the assisted ammonolysis are 20-80 kJ/mol lower than those for the non-assisted reaction.展开更多
To understand the reaction behaviour of the reactive dye with amino groups on protein fibres,the reaction kinetics of competitive hydrolysis and ammonolysis of a monochlorotriazina reactive dye were studied at 50-80℃...To understand the reaction behaviour of the reactive dye with amino groups on protein fibres,the reaction kinetics of competitive hydrolysis and ammonolysis of a monochlorotriazina reactive dye were studied at 50-80℃ and pH=8-10 by high performance liquid chromatography(HPLC).The results showed the pseudo-first-order phenomenon for the general reaction of concurrent hydrolysis and ammonolysis of the dyes.The ammonolysis reaction was always faster than the hydrolysis reaction in the range of temperature and pH employed,but the preference for ammonolysis to hydrolysis reaction decreased with the increase of temperature and pH value.The ratios of ammonolysis/hydrolysis rate constant reduced from 17.6 to 5.4 when the temperature increased from 50 to 80℃ in pH=10,and from 7.2 to 5.4 when the pH value increased from 8 to 10 at 80℃.展开更多
Studying urea formation by ammonolysis of propylene carbonate in a liquid phase showed that this process is two-stage, and proceeds through preferred formation of 2-hydroxypropyl carbamate, besides, the rate of the fi...Studying urea formation by ammonolysis of propylene carbonate in a liquid phase showed that this process is two-stage, and proceeds through preferred formation of 2-hydroxypropyl carbamate, besides, the rate of the first stage is much higher than the rate of the second stage （urea formation）. With the aid of the HPLC and HPLC/MS methods found some other intermediate products and offered consecutive-parallel scheme of the process. The obtained results explain the composition of impurities obtained during the production of the 13C-urea for diagnostic breath tests.展开更多
Three peptide alcohols and four peptidyl N-akyl-amides were prepared by a series-connection procedure consisting of n-1 sequencial assembly on solid support followed by ammonolysis with glycinol, benzylamine or n-bu...Three peptide alcohols and four peptidyl N-akyl-amides were prepared by a series-connection procedure consisting of n-1 sequencial assembly on solid support followed by ammonolysis with glycinol, benzylamine or n-butylamine, and successive extractionelution through C-18 layer. All products were obtained from this procedure without further purification, in an overall yield of 75-86%.展开更多
In the quest for novel PPARα/γ dual agonists as putative drugs for the treatment of type 2 diabetes and dyslipidemia, we designed and synthesized a series of urea acetates as potential PPARα/γ dual agonists. The s...In the quest for novel PPARα/γ dual agonists as putative drugs for the treatment of type 2 diabetes and dyslipidemia, we designed and synthesized a series of urea acetates as potential PPARα/γ dual agonists. The structure of the target compounds, intermediates were characterized by ^1H N-MR, HRMS.展开更多
Literature data dedicated to formation of 4-phenylphthalonitrile were analyzed and generalized. As a result of the own studies, it has been established that on V–Sb–Bi–Zr/γ-Al2O3-oxide catalyst ammoxidation gives ...Literature data dedicated to formation of 4-phenylphthalonitrile were analyzed and generalized. As a result of the own studies, it has been established that on V–Sb–Bi–Zr/γ-Al2O3-oxide catalyst ammoxidation gives 83.10 mol.% 4-phenylphthalonitrile at high conversion of the initial 4-phenyl-o-xylene in a single process. In connection with increased demand to purity of 4-phe-nylphthalonitrile at using and division problem of hard-separable impurity of crystal 4-phe-nylphthalimide, a variant of the technological process design with average conversion and recirculation of the unreacted 4-phenyl-o-xylene and intermediate 4-phenyl-o-tolunitrile was proposed. In contrast to the single process, it has been determined that recirculation reduces quantity of form by-products, fractions of deep oxidation and increases selectivity on 4-phenylphthalonitrile up to 96.14% - 97.72%. For the data analysis and visualization of results it is developed and offered the software package of OptimMe written in C#.展开更多
On the basis of kinetic data of 4-phenyl-o-xylene and 4-phenyl-o-tolunitrile ammoxidation, formation mechanism of the products was analyzed and generalized. It has been shown that dissociative adsorption of a substrat...On the basis of kinetic data of 4-phenyl-o-xylene and 4-phenyl-o-tolunitrile ammoxidation, formation mechanism of the products was analyzed and generalized. It has been shown that dissociative adsorption of a substrate and mononitrile occurs on the centers with high heats of adsorption of oxygen and as a consequence, completely covered with it, competitive adsorption of NH3 and O2 occurs on the centers with low heats of adsorption of the latter;mononitrile and dinitrile are formed correspondingly from adsorbed fragments of both substrate and NH3, and tolunitrile and NH3;surface interaction of adsorbed fragments of substrate and O2 with low heat of adsorption gives imide and CO2;hydrolysis of dinitrile into imide occurs on centers completely covered with ammonia;imide decarboxylation occurs on the centers covered with it;oxidative destruction of tolunitrile occurs on centers covered with substrate and mononitrile.展开更多
An efficient method for the synthesis of N-Cbz-β-aminoalkanesulfonamides was described.N-Cbz-β-aminoalkanesulfonamides were readily prepared in good yields from a variety of amino alcohols,including optically active...An efficient method for the synthesis of N-Cbz-β-aminoalkanesulfonamides was described.N-Cbz-β-aminoalkanesulfonamides were readily prepared in good yields from a variety of amino alcohols,including optically active ones,via N-Cbz protection with benzyl chloroformate,Mitsunobu esterification reaction with thiolacetic acid,N-chlorosuccinimide oxidation,and ammonolysis process.展开更多
A series of C-7 modified analogues of casuarine have been synthesized from sugar-derived nitrone and assayed against various glycosidases. Introduction of C-7 aminomethyl or amide group led to sharp decrease of the in...A series of C-7 modified analogues of casuarine have been synthesized from sugar-derived nitrone and assayed against various glycosidases. Introduction of C-7 aminomethyl or amide group led to sharp decrease of the inhibitory activities.展开更多
文摘The ring opening of β-sultam v/a an H2O-assisted ammonolysis process was studied by using Density Functional Theory（DFT） method at the B3LYP/6-31G level as a further step in the theoretical investigation of the ammonolysis reaction of β-sultams. The calculated pathways are analogous to those previously described for the non-assisted ammonolysis reaction. Solvent effects were assessed by using the polarized continuum model（PCM） method. The results show that mode 1 and pathway a in channel Ⅱ are the most favorable ones in both the cases. The energy barrier of the cleavage of C-S bonds producing P1 is the highest among all the energy barriers. The presence of a solvent in the continuum model disfavors the reaction, whereas the participation of water in the ammonolysis reaction plays a positive role and reduces the active energy greatly. The relative energies of all the transition states in the assisted ammonolysis are 20-80 kJ/mol lower than those for the non-assisted reaction.
文摘To understand the reaction behaviour of the reactive dye with amino groups on protein fibres,the reaction kinetics of competitive hydrolysis and ammonolysis of a monochlorotriazina reactive dye were studied at 50-80℃ and pH=8-10 by high performance liquid chromatography(HPLC).The results showed the pseudo-first-order phenomenon for the general reaction of concurrent hydrolysis and ammonolysis of the dyes.The ammonolysis reaction was always faster than the hydrolysis reaction in the range of temperature and pH employed,but the preference for ammonolysis to hydrolysis reaction decreased with the increase of temperature and pH value.The ratios of ammonolysis/hydrolysis rate constant reduced from 17.6 to 5.4 when the temperature increased from 50 to 80℃ in pH=10,and from 7.2 to 5.4 when the pH value increased from 8 to 10 at 80℃.
文摘Studying urea formation by ammonolysis of propylene carbonate in a liquid phase showed that this process is two-stage, and proceeds through preferred formation of 2-hydroxypropyl carbamate, besides, the rate of the first stage is much higher than the rate of the second stage （urea formation）. With the aid of the HPLC and HPLC/MS methods found some other intermediate products and offered consecutive-parallel scheme of the process. The obtained results explain the composition of impurities obtained during the production of the 13C-urea for diagnostic breath tests.
基金supported by the National Natural Science Foundation of China,grants No.30271530.
文摘Three peptide alcohols and four peptidyl N-akyl-amides were prepared by a series-connection procedure consisting of n-1 sequencial assembly on solid support followed by ammonolysis with glycinol, benzylamine or n-butylamine, and successive extractionelution through C-18 layer. All products were obtained from this procedure without further purification, in an overall yield of 75-86%.
文摘In the quest for novel PPARα/γ dual agonists as putative drugs for the treatment of type 2 diabetes and dyslipidemia, we designed and synthesized a series of urea acetates as potential PPARα/γ dual agonists. The structure of the target compounds, intermediates were characterized by ^1H N-MR, HRMS.
文摘Literature data dedicated to formation of 4-phenylphthalonitrile were analyzed and generalized. As a result of the own studies, it has been established that on V–Sb–Bi–Zr/γ-Al2O3-oxide catalyst ammoxidation gives 83.10 mol.% 4-phenylphthalonitrile at high conversion of the initial 4-phenyl-o-xylene in a single process. In connection with increased demand to purity of 4-phe-nylphthalonitrile at using and division problem of hard-separable impurity of crystal 4-phe-nylphthalimide, a variant of the technological process design with average conversion and recirculation of the unreacted 4-phenyl-o-xylene and intermediate 4-phenyl-o-tolunitrile was proposed. In contrast to the single process, it has been determined that recirculation reduces quantity of form by-products, fractions of deep oxidation and increases selectivity on 4-phenylphthalonitrile up to 96.14% - 97.72%. For the data analysis and visualization of results it is developed and offered the software package of OptimMe written in C#.
文摘On the basis of kinetic data of 4-phenyl-o-xylene and 4-phenyl-o-tolunitrile ammoxidation, formation mechanism of the products was analyzed and generalized. It has been shown that dissociative adsorption of a substrate and mononitrile occurs on the centers with high heats of adsorption of oxygen and as a consequence, completely covered with it, competitive adsorption of NH3 and O2 occurs on the centers with low heats of adsorption of the latter;mononitrile and dinitrile are formed correspondingly from adsorbed fragments of both substrate and NH3, and tolunitrile and NH3;surface interaction of adsorbed fragments of substrate and O2 with low heat of adsorption gives imide and CO2;hydrolysis of dinitrile into imide occurs on centers completely covered with ammonia;imide decarboxylation occurs on the centers covered with it;oxidative destruction of tolunitrile occurs on centers covered with substrate and mononitrile.
基金the support from the National Natural Science Foundation of China(20973013)Beijing Natural Science Foundation(2092022)
文摘An efficient method for the synthesis of N-Cbz-β-aminoalkanesulfonamides was described.N-Cbz-β-aminoalkanesulfonamides were readily prepared in good yields from a variety of amino alcohols,including optically active ones,via N-Cbz protection with benzyl chloroformate,Mitsunobu esterification reaction with thiolacetic acid,N-chlorosuccinimide oxidation,and ammonolysis process.
基金Financial support from the National Natural Science Foundation of China(Nos.21642012 and 21272240)National Science and Technology Major Projects for“Major New Drugs Innovation and Development”(No.2013ZX09508104)+1 种基金National Engineering Research Center for Carbohydrate Synthesis of Jiangxi Normal Universitysupported in part by a Grant-in-Aid for Scientific Research(C)(No.26460143)(AK)from the Japanese Society for the Promotion of Science(JSPS)
文摘A series of C-7 modified analogues of casuarine have been synthesized from sugar-derived nitrone and assayed against various glycosidases. Introduction of C-7 aminomethyl or amide group led to sharp decrease of the inhibitory activities.
