A series of 1,3-bis（2-alkyltetrazol-5-yl）triazenes have been synthesized in high yields by treatment of sodium nitrite and hydrochloric acid with substituted-5-aminotetrazoles. All compounds were fully characterized...A series of 1,3-bis（2-alkyltetrazol-5-yl）triazenes have been synthesized in high yields by treatment of sodium nitrite and hydrochloric acid with substituted-5-aminotetrazoles. All compounds were fully characterized using IR spectroscopy,~1H NMR and^（13） C NMR spectroscopy and high resolution mass spectrometer（HRMS）. Most of these triazenes exhibit good detonation performance comparable with TNT and low melting points ranging from 81°C to 106°C, which are suitable for melt-cast explosives.Among these compounds, 1,3-bis（2-azidoethyltetrazol-5-yl）triazene（2g） displays a low melting point（106°C）, moderate onset decomposition temperature（183°C） and good detonation performance（D：7087 m/s; P： 17.6 GPa）.展开更多
A combination of tetrachlorosilane（TCS） and phenol in dichloromethane was found to be an efficient reagent for hydro-chlorination ofα,β-unsaturated ketones to afford the correspondingβ-chloroketones in good yield...A combination of tetrachlorosilane（TCS） and phenol in dichloromethane was found to be an efficient reagent for hydro-chlorination ofα,β-unsaturated ketones to afford the correspondingβ-chloroketones in good yield at ambient temperature. Reactions of the titled compounds with TCS-NaN_3 as well as with nitriles utilizing TCS-ZnCl_2 to give 1,5-disubstituted tetrazole derivatives orβ-amido ketones respectively are also described.展开更多
A systematic study of TKX-50 and ABTOX synthesis using both Klap6tke and Tselinskii modified procedures is described. The influence of temperature, moisture, acid amount and nature on the most critical synthesis step ...A systematic study of TKX-50 and ABTOX synthesis using both Klap6tke and Tselinskii modified procedures is described. The influence of temperature, moisture, acid amount and nature on the most critical synthesis step - diazidoglyoxime cyclization is shown. Experimental results show that presence of moisture in reaction mixture leads to product yield decreasing. The reaction temperature is another key parameter affecting product yield. High reaction temperature shows negative influence on the product yield in Klap6tke method. In Tselinskii procedure the yield of product grows with the reaction temperature increasing. For Klap6tke one-pot method, combination of N-methyl-2-pyrrolidone with 1,4-dioxane is the best solvent, whereas Tselinskii one-pot procedure gives high yield of product when combination of toluene with 0.5 equiv, of 1,8-diazabicyclo[5.4.0]undec-7-ene （DBU） is used. Us- ing optimized conditions one-pot five-step synthesis of TKX-50 starting from glyoxime is successfully performed and scaled up to 50 g.展开更多
A practical and metal-flee oxidative amidation of aldehydes with tetrazoles into 1,3,4-oxadiazoles has been de- veloped by employing tetrabutylammonium iodide （TBAI） as catalyst and tert-butyl hydroperoxide （TBHP）...A practical and metal-flee oxidative amidation of aldehydes with tetrazoles into 1,3,4-oxadiazoles has been de- veloped by employing tetrabutylammonium iodide （TBAI） as catalyst and tert-butyl hydroperoxide （TBHP） as oxidant. A wide range of 2,5-disubstituted 1,3,4-oxadiazoles can be conveniently generated in moderate to good yields. Gram-scale reaction was also realized in this catalytic system.展开更多
The reaction of picoline derivatives 3-6 with hydrazonoylhalide 1a produced imidazo[1,2-a]pyridines 7-10, while the reaction of the same picoline derivatives with hydrazonoylhalide 1b afforded imidazo[1,2-a]pyridine-2...The reaction of picoline derivatives 3-6 with hydrazonoylhalide 1a produced imidazo[1,2-a]pyridines 7-10, while the reaction of the same picoline derivatives with hydrazonoylhalide 1b afforded imidazo[1,2-a]pyridine-2-ones 11-13. The reaction of 1b, c with 3-amino-1,2,4-triazole 14 produced the acyclic adducts 18 and 19, respectively. Reaction of 1b, 1c with 5-aminotetrazole 20 produced the acyclic products 23 and 24, respectively. Finally, the reaction of 1b with 4, 6-dimethyl-2-aminopyrimidine 27 afforded compound 29 rather than its isomeric structure 28. The structure of the products was confirmed by the different spectroscopic analytical methods including IR, MS, 1HNMR and 13CNMR.展开更多
OBJECTIVE: To explore the pathogenic changes of myocardial apoptosis in heart hypertrophy during hypertension and evaluate the anti-apoptosis effect of Valsartan. METHODS: Thirty spontaneously hypertensive rats (SHRs)...OBJECTIVE: To explore the pathogenic changes of myocardial apoptosis in heart hypertrophy during hypertension and evaluate the anti-apoptosis effect of Valsartan. METHODS: Thirty spontaneously hypertensive rats (SHRs) were divided into two groups: 15 treated with Valsartan (20 mg x kg(-1) x d(-1)) (SHR + Valsartan group), the others with placebo (SHR + placebo group), with 15 normal Wistar rats as control. Systolic blood pressure was measured by the tail-cuff method. The observation period was from 8 to 16 weeks of age. Cardiac apoptosis was evaluated by a Terminal Deoxynucleotidyl Transferase-Mediated dUTP-biotin Nick End Labeling (TUNEL) assay. RESULTS: Mean blood pressure values were 127 +/- 2 mm Hg in controls, 163 +/- 6 mm Hg in the SHR + Valsartan group and 193 +/- 7 mm Hg in the SHR + placebo group at 16 weeks of age, whereas the blood pressure in 8-week-old SHR and Wistar rats were 175 +/- 3 mm Hg and 125 +/- 5 mm Hg, respectively. The ratio of the heart weight over body weight declined in Wistar (3.07 +/- 0.03 mg/g) and SHR + Valsartan groups (3.22 +/- 0.19 mg/g) compared with the SHR + placebo group (4.02 +/- 0.31 mg/g) (P展开更多
Recyclable CuO nanoparticles were successfully employed to catalyze the microwave‐assisted(3+2)cycloaddition reaction between nitriles and NaN3to efficiently synthesize5‐substituted1H‐tetrazoles.The salient feature...Recyclable CuO nanoparticles were successfully employed to catalyze the microwave‐assisted(3+2)cycloaddition reaction between nitriles and NaN3to efficiently synthesize5‐substituted1H‐tetrazoles.The salient features associated with this protocol are its cost effectiveness,rapid synthesis,stability,reusability,mild reaction conditions without any additives,high tolerance to various functional groups,and excellent yields under microwave irradiation.This environmentally friendly,microwave‐assisted,nanoparticle‐catalyzed synthetic methodology is seen as an alternative to conventional procedures that involve Lewis acid catalysts and a simple operation to the privileged scaffold.展开更多
Certain N-cyanoalkyl-functionalized imidazolium halide salts unexpectedly undergo nitrile hydrolysis to amides, as well as dipolar cycloaddition to tetrazoles when eluted on azide anion exchanged resin.
基金Financial support of this work from the National Natural Science Foundation of China(No.21372027)
文摘A series of 1,3-bis（2-alkyltetrazol-5-yl）triazenes have been synthesized in high yields by treatment of sodium nitrite and hydrochloric acid with substituted-5-aminotetrazoles. All compounds were fully characterized using IR spectroscopy,~1H NMR and^（13） C NMR spectroscopy and high resolution mass spectrometer（HRMS）. Most of these triazenes exhibit good detonation performance comparable with TNT and low melting points ranging from 81°C to 106°C, which are suitable for melt-cast explosives.Among these compounds, 1,3-bis（2-azidoethyltetrazol-5-yl）triazene（2g） displays a low melting point（106°C）, moderate onset decomposition temperature（183°C） and good detonation performance（D：7087 m/s; P： 17.6 GPa）.
文摘A combination of tetrachlorosilane（TCS） and phenol in dichloromethane was found to be an efficient reagent for hydro-chlorination ofα,β-unsaturated ketones to afford the correspondingβ-chloroketones in good yield at ambient temperature. Reactions of the titled compounds with TCS-NaN_3 as well as with nitriles utilizing TCS-ZnCl_2 to give 1,5-disubstituted tetrazole derivatives orβ-amido ketones respectively are also described.
文摘A systematic study of TKX-50 and ABTOX synthesis using both Klap6tke and Tselinskii modified procedures is described. The influence of temperature, moisture, acid amount and nature on the most critical synthesis step - diazidoglyoxime cyclization is shown. Experimental results show that presence of moisture in reaction mixture leads to product yield decreasing. The reaction temperature is another key parameter affecting product yield. High reaction temperature shows negative influence on the product yield in Klap6tke method. In Tselinskii procedure the yield of product grows with the reaction temperature increasing. For Klap6tke one-pot method, combination of N-methyl-2-pyrrolidone with 1,4-dioxane is the best solvent, whereas Tselinskii one-pot procedure gives high yield of product when combination of toluene with 0.5 equiv, of 1,8-diazabicyclo[5.4.0]undec-7-ene （DBU） is used. Us- ing optimized conditions one-pot five-step synthesis of TKX-50 starting from glyoxime is successfully performed and scaled up to 50 g.
基金This project was financially supported by the National Natural Science Foundation of China （No. 21302014） and the Natural Science Foundation for Colleges and Universities of Jiangsu Province （No. 13KJB 150002）.
文摘A practical and metal-flee oxidative amidation of aldehydes with tetrazoles into 1,3,4-oxadiazoles has been de- veloped by employing tetrabutylammonium iodide （TBAI） as catalyst and tert-butyl hydroperoxide （TBHP） as oxidant. A wide range of 2,5-disubstituted 1,3,4-oxadiazoles can be conveniently generated in moderate to good yields. Gram-scale reaction was also realized in this catalytic system.
文摘The reaction of picoline derivatives 3-6 with hydrazonoylhalide 1a produced imidazo[1,2-a]pyridines 7-10, while the reaction of the same picoline derivatives with hydrazonoylhalide 1b afforded imidazo[1,2-a]pyridine-2-ones 11-13. The reaction of 1b, c with 3-amino-1,2,4-triazole 14 produced the acyclic adducts 18 and 19, respectively. Reaction of 1b, 1c with 5-aminotetrazole 20 produced the acyclic products 23 and 24, respectively. Finally, the reaction of 1b with 4, 6-dimethyl-2-aminopyrimidine 27 afforded compound 29 rather than its isomeric structure 28. The structure of the products was confirmed by the different spectroscopic analytical methods including IR, MS, 1HNMR and 13CNMR.
文摘OBJECTIVE: To explore the pathogenic changes of myocardial apoptosis in heart hypertrophy during hypertension and evaluate the anti-apoptosis effect of Valsartan. METHODS: Thirty spontaneously hypertensive rats (SHRs) were divided into two groups: 15 treated with Valsartan (20 mg x kg(-1) x d(-1)) (SHR + Valsartan group), the others with placebo (SHR + placebo group), with 15 normal Wistar rats as control. Systolic blood pressure was measured by the tail-cuff method. The observation period was from 8 to 16 weeks of age. Cardiac apoptosis was evaluated by a Terminal Deoxynucleotidyl Transferase-Mediated dUTP-biotin Nick End Labeling (TUNEL) assay. RESULTS: Mean blood pressure values were 127 +/- 2 mm Hg in controls, 163 +/- 6 mm Hg in the SHR + Valsartan group and 193 +/- 7 mm Hg in the SHR + placebo group at 16 weeks of age, whereas the blood pressure in 8-week-old SHR and Wistar rats were 175 +/- 3 mm Hg and 125 +/- 5 mm Hg, respectively. The ratio of the heart weight over body weight declined in Wistar (3.07 +/- 0.03 mg/g) and SHR + Valsartan groups (3.22 +/- 0.19 mg/g) compared with the SHR + placebo group (4.02 +/- 0.31 mg/g) (P
基金CSIR-Govt of India for funding through Grant No. 01(2913)/17/EMR-II
文摘Recyclable CuO nanoparticles were successfully employed to catalyze the microwave‐assisted(3+2)cycloaddition reaction between nitriles and NaN3to efficiently synthesize5‐substituted1H‐tetrazoles.The salient features associated with this protocol are its cost effectiveness,rapid synthesis,stability,reusability,mild reaction conditions without any additives,high tolerance to various functional groups,and excellent yields under microwave irradiation.This environmentally friendly,microwave‐assisted,nanoparticle‐catalyzed synthetic methodology is seen as an alternative to conventional procedures that involve Lewis acid catalysts and a simple operation to the privileged scaffold.
基金supported by the US Air Force Office of Scientific Research (F49550-10-1-0521)
文摘Certain N-cyanoalkyl-functionalized imidazolium halide salts unexpectedly undergo nitrile hydrolysis to amides, as well as dipolar cycloaddition to tetrazoles when eluted on azide anion exchanged resin.
