A highly efficient copper-catalyzed approach to form amide bonds from formamides and carboxylic acids was developed. This protocol shows broad substrate scopes and high yields in the presence of 1 mol% catalyst and 4....A highly efficient copper-catalyzed approach to form amide bonds from formamides and carboxylic acids was developed. This protocol shows broad substrate scopes and high yields in the presence of 1 mol% catalyst and 4.0 equiv, formamides.展开更多
Hydrogel is considered as an important material in our world nowadays as it is used in many important and significant applications such as in tissue engineering and agriculture. There are hundreds of types of such mat...Hydrogel is considered as an important material in our world nowadays as it is used in many important and significant applications such as in tissue engineering and agriculture. There are hundreds of types of such materials, where most of them can be easily prepared. The main objective of this work is to prepare one of the hydrogel types which could be very useful in the agriculture of deserts where plants in dry places require water in order to grow up. There are many places around the world where raining occurs only once or twice a year. There are also places where it does not rain at all. Therefore, hydrogels are required in order to absorb water in large quantities either during raining or irrigation instead of escaping to underground and then eject them to the roots of plants over time as the plants require watering. In this research a hydrogel based on acryl amide, Poly 2-Acrylamide-2-Methyl-1-Propane Sulphonic Acid, (PAMPS) was prepared by using different percentages of a suitable cross-linking agent, Methylene-bis-Acrylamide. The cross-linker content is very important factor affects the rate and amount of absorbed water. The highest amount of absorbed water at 25°C was observed by using 0.6% cross-linking agent based on monomer mass. The temperature of absorbed water and its pH value are also essential factors that affect the rate and the amount of absorbed water and were investigated in this work. The highest amount of absorbed water was recorded at pH = 12 and at 60°C. The amount and the rate of water absorbed by Sodium Polyacrylate Hydrogel were also investigated at 25°C. The agriculture applications of hydrogel based on Sodium Polyacrylate were examined using Fenugreek seeds implanting.展开更多
Novel aromatic-aliphatic poly(amide-imide)s containing chiral units in the main chain and hydroxyl benzamide units in the side chain have been obtained from the step-growth polymerization of 3,5-diamino-N-(4-hydrox...Novel aromatic-aliphatic poly(amide-imide)s containing chiral units in the main chain and hydroxyl benzamide units in the side chain have been obtained from the step-growth polymerization of 3,5-diamino-N-(4-hydroxyphenyl) benzamide (2) with different chiral diacid chlorides (la-le). Theoretical calculations were done by means of computational chemistry methods to narrate the stable conformation and orientation of each diacid chloride monomers under reaction conditions. These polymers were characterized by conventional techniques. The resulting polymers show good thermal stability. Other physical properties of polymers including crystallinity, inherent viscosity and morphological characteristics were also studied.展开更多
Natural bioactive compounds from plants are of great importance in modern therapeutics,which are used to prepare antibiotics, growth supplements or some other therapeutics. Ltheanine is such a bioactive amide amino ac...Natural bioactive compounds from plants are of great importance in modern therapeutics,which are used to prepare antibiotics, growth supplements or some other therapeutics. Ltheanine is such a bioactive amide amino acid presented in different plants and fungi,especially in tea. Theanine has influential effects on lifestyle associated diseases, such as diabetes, cardiovascular disorders, hypertension, stress relief, tumor suppression,menstruation and liver injury. This amino acid can maintain normal sleep and improve memory function and nullify effect of the neurotoxins. The rate of bioavailability and its medium of ingestion in the body is one of the great concerns for its additional antioxidant properties. Pharmacokinetics of the bioactive compound and its mode of action are described herewith. The biosynthesis and industrial synthesis are also reviewed to promote accelerated production of this bioactive compound in the pharmaceutical industries.展开更多
A new wo-armed?acyclic diamide Ia 2, 6-bis(1-ethanecarbozamido-2-amino)pyridine, and a new series of aromatic aldehyde schiff bases containing pyridine ring and amide bridge, IIa-f, were prepared. The compounds were...A new wo-armed?acyclic diamide Ia 2, 6-bis(1-ethanecarbozamido-2-amino)pyridine, and a new series of aromatic aldehyde schiff bases containing pyridine ring and amide bridge, IIa-f, were prepared. The compounds were characterized by elemental analysis, IR, 1HNMR and MS. The bioactivity half inhibitory concentration C1/2 is given.展开更多
Ursolic acid was modified at C3 and C28 position to obtain fourteen derivatives including twelve novel compounds, and their chemical structures were characterized by IR, ^1H NMR and MS. Cell growth inhibitory effects ...Ursolic acid was modified at C3 and C28 position to obtain fourteen derivatives including twelve novel compounds, and their chemical structures were characterized by IR, ^1H NMR and MS. Cell growth inhibitory effects of the derivatives against Hela cell were evaluated by MTT assay. All these derivatives were found to have stronger cell growth inhibitory than their parent compound, ursolic acid. The derivatives with a substituted acetyl group at C3 hydroxyl group show better activities than those with an unsubstituted hydroxyl group.展开更多
The development of economic and environmentally friendly extractants to recover cobalt metal is required due to the increasing demand for this metal.In this study,solvent extraction of Co(Ⅱ) from aqueous solution u...The development of economic and environmentally friendly extractants to recover cobalt metal is required due to the increasing demand for this metal.In this study,solvent extraction of Co(Ⅱ) from aqueous solution using a mixture of N,N'-carbonyl difatty amides(CDFAs) synthesised from palm oil as the extractant was carried out.The effects of various parameters such as acid,contact time,extractant concentration,metal ion concentration and stripping agent and the separation of Co(Ⅱ) from other metal ions such as Fe(Ⅱ),Ni(Ⅱ),Zn(Ⅲ) and Cd(Ⅱ) were investigated.It was found that the extraction of Co(Ⅱ) into the organic phase involved the formation of 1:1 complexes.Co(Ⅱ) was successfully separated from commonly associated metal ions such as Fe(Ⅱ),Ni(Ⅱ),Zn(Ⅲ) and Cd(Ⅱ).Co(Ⅱ) stripping from the loaded organic phase was studied in aqueous solution.These results are useful to recover Co(Ⅱ) from aqueous solution utilising(CDFAs) as an extractant.展开更多
Based on the similarities in the conformation of VS008(N-(4-methylphenyl)-3-(tert-butyl)-1-(phenylmethyl)-1H-pyrazole-5-carboxamide) and BYIO6830(N'-(3,5-dimethylbenzoyl)-N'-tert-butyl-5-methyl-2,3-dihydr...Based on the similarities in the conformation of VS008(N-(4-methylphenyl)-3-(tert-butyl)-1-(phenylmethyl)-1H-pyrazole-5-carboxamide) and BYIO6830(N'-(3,5-dimethylbenzoyl)-N'-tert-butyl-5-methyl-2,3-dihydro-l,4-benzodioxine-6-carbohydrazide) bound to the active site of the EcR subunit of the ecdysone receptor(EcR)-ultraspiracle protein(USP) heterodimeric receptor,a series of new pyrazole amide derivatives were designed and synthesized.Their structures were confirmed by IR,~1H NMR,^(13)C NMR and elemental analysis.Results from a preliminary bioassay revealed that two of the pyrazole derivatives exhibited promising insecticidal activity.Specifically,compounds 6e and 6i exhibited good activity against Helicoverpa armigera(cotton bollworm) at low concentration.Symptoms displayed by tebufenozide-treated H.armigera were identical with those displayed by its treated counterpart.6i showed the same poisoning symptoms as those of tebufenozide.In addition,results from molecular docking result indicated that the binding modes of 6e and 6i at the active site of the EcR subunit of the heterodimeric receptor were similar to that of the bound tebufenozide.展开更多
(S)-(+)-2,2-dimethylcyclopropane carbox amide is a key intermediate of Cilastatin, an inhibitor of de- hydropeptidase-I. Its corresponding solid-liquid equilibrium data will provide essential support for industrial de...(S)-(+)-2,2-dimethylcyclopropane carbox amide is a key intermediate of Cilastatin, an inhibitor of de- hydropeptidase-I. Its corresponding solid-liquid equilibrium data will provide essential support for industrial design and further theoretical studies. The solubilities of (S)-(+)-2,2-dimethylcyclopropane carbox amide in toluene, di- chloromethane, trichloromethane, ethyl acetate, ethanol and pure water at different temperature were measured us- ing the synthetic method by a laser monitoring observation technique. The solubility data were correlated with the modified Apelblat equation. The calculated values were good in agreement with the experimental values.展开更多
In order to discover highly active ecdysone analogs, a series of new substituted pyrazole amide derivatives were obtained using structure-guided optimization method and further screened for their insecticidal activiti...In order to discover highly active ecdysone analogs, a series of new substituted pyrazole amide derivatives were obtained using structure-guided optimization method and further screened for their insecticidal activities, in the basis of the core structures of the two active compounds N-(3-methoxyphenyl)-3-(tert-butyl)-1-phenyl-1H-pyrazole-5-carboxamide(6e) and N-(4-(tert-butyl)phenyl)-3-(tert-butyl)-1-phenyl-1H-pyrazole-5-carboxamide(6i), previously presented by us. The chemical structures of the title compounds were identified by spectral analyses. The preliminary bioassay results indicated that one among the synthesized pyrazole derivatives, compound 34, endowed with good activity against Mythimna Separata at 10 mg/L, which was equal to that displayed by the positive control tebufenozide. In addition, examples of molecular docking and molecular dynamics studies demonstrated that 34 may be the potential inhibitor to Ec R and its docking conformation was similar to that of tebufenozide. In addition, increasing the hydrophobic effect and considering the suitable bulk effect on pyrazole ring are beneficial to the inhibiting activity to Ec R and activity in vivo.展开更多
A new series of 12-benzyl matrinic amide/ethanamide derivatives were synthesized from matrinine(1)and evaluated for their anti-HCV activity,taking compound 2 as the lead.SAR revealed that the introduction of a suita...A new series of 12-benzyl matrinic amide/ethanamide derivatives were synthesized from matrinine(1)and evaluated for their anti-HCV activity,taking compound 2 as the lead.SAR revealed that the introduction of a suitable substituent at the N’-end of matrinic amide might greatly enhance the potency.Among them,matrinic acid 17 and N’-substituted matrinic amides 18a-d exhibited promising potency with low micromolar EC50 values ranging from 1.03μmol/L to 7.54 μmol/L,and better therapeutic window with SI from 66 to 132.Moreover,compound 17 displayed an excellent PK and safety profile in vivo,demonstrating good drug-like characteristics.Thus,it has been selected for further investigation,with an advantage of decreased chances of inducing drug-resistance mutations.展开更多
Two novel heterocyclic diamine monomers: 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl] (2H)phthalazin-1-one and 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)-3,5-dimethylphenyl](2H)phthalazin-1-one ...Two novel heterocyclic diamine monomers: 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl] (2H)phthalazin-1-one and 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)-3,5-dimethylphenyl](2H)phthalazin-1-one were successfully synthesized from readily available heterocyclic bisphenol-like monomers in two steps in high yield. A series of novel poly(aryl ether amide)s containing the phthalazinone moiety were successfully prepared by the direct polymerization of the novel diamines and aromatic dicarboxylic acids using triphenyl phosphite and pyridine as condensing agents.展开更多
Four gemini cationic surfactants {N,N′-di[2-(lauryldimethylamino)acetyl]polymethylenediamine dichloride, LAA-s-LAA, s=2,3,4,6} were synthesized by using four bis(α-chloroacetamide)s and N,N-dimethyllaurylamine, resp...Four gemini cationic surfactants {N,N′-di[2-(lauryldimethylamino)acetyl]polymethylenediamine dichloride, LAA-s-LAA, s=2,3,4,6} were synthesized by using four bis(α-chloroacetamide)s and N,N-dimethyllaurylamine, respectively. The molecular structures were characterized by means of IR, ~ 1H NMR, \{~ ~13 C NMR\} and MS, and the behavior of their aqueous solutions was studied. The critical micell concentrations(CMC) of LAA-s-LAA were one order of magnitude lower than that of dodecyltrimethyl ammonium chloride(DTAC). With the change of the length of spacer chain(s), their CMC values change, and CMC reaches the top value at s=4.展开更多
Amide ionic liquids (MLs)/L-proline synergistic catalyzed Mannich reactions of isovaleraldehyde, methyl ketones, and aromatic amines were carried out in moderate to high yields ( up to 96% ) and high stereo select...Amide ionic liquids (MLs)/L-proline synergistic catalyzed Mannich reactions of isovaleraldehyde, methyl ketones, and aromatic amines were carried out in moderate to high yields ( up to 96% ) and high stereo selectivities ( 〉99% e. e. ). The products were easily isolated by extraction; and the catalyst system was readily recycled at least thrice without significant loss of efficiency. The scope of the substrates was studied and the interpretation of the manifest improvement of the reaction rates and enantio-selectivity of the novel catalyst system was speculated.展开更多
The coupling reaction of phenylurea with different functionalized aryl halides in the presence of air stable CuI,N,N-dimethylethylenediamine as a ligand,and K_3PO_4 as a base gives symmetrical and unsymmetrical diaryl...The coupling reaction of phenylurea with different functionalized aryl halides in the presence of air stable CuI,N,N-dimethylethylenediamine as a ligand,and K_3PO_4 as a base gives symmetrical and unsymmetrical diarylureas in relatively high yields.This method is milder than the palladium catalyzed arylation and avoids the use of toxic phosphine ligands.展开更多
Five DTPA bis(amide)s have been synthesized and characterized by means of 1 H NMR , FT IR and elemental analyses. The stability constants of their Gd 3+ complexes have been measured using a simple spec...Five DTPA bis(amide)s have been synthesized and characterized by means of 1 H NMR , FT IR and elemental analyses. The stability constants of their Gd 3+ complexes have been measured using a simple spectrophotometric method. The results show that the complexing properties of the ligands in comparison with those of DTPA are affected by converting two carboxyl groups to amide groups. The relaxation studies have shown that the relaxivity of the chelates is similar to that of Gd DTPA, indicating that in solution all the chelates have one water molecule directly coordinated to the metal ion. Only one water molecule in inner coordination sphere suggests the coordination of the carboxamide oxygen to gadolinium ion, which agrees with the FT IR results.展开更多
基金supported by the National Natural Science Foundation of China(No.21372176)Tongji University 985 Phase Ⅲ funds+1 种基金Pujiang Project of Shanghai Science and Technology Commission(No.11 J1409800)the Program for Professor of Special Appointment(Eastern Scholar) at Shanghai Institutions of Higher Learning
文摘A highly efficient copper-catalyzed approach to form amide bonds from formamides and carboxylic acids was developed. This protocol shows broad substrate scopes and high yields in the presence of 1 mol% catalyst and 4.0 equiv, formamides.
文摘Hydrogel is considered as an important material in our world nowadays as it is used in many important and significant applications such as in tissue engineering and agriculture. There are hundreds of types of such materials, where most of them can be easily prepared. The main objective of this work is to prepare one of the hydrogel types which could be very useful in the agriculture of deserts where plants in dry places require water in order to grow up. There are many places around the world where raining occurs only once or twice a year. There are also places where it does not rain at all. Therefore, hydrogels are required in order to absorb water in large quantities either during raining or irrigation instead of escaping to underground and then eject them to the roots of plants over time as the plants require watering. In this research a hydrogel based on acryl amide, Poly 2-Acrylamide-2-Methyl-1-Propane Sulphonic Acid, (PAMPS) was prepared by using different percentages of a suitable cross-linking agent, Methylene-bis-Acrylamide. The cross-linker content is very important factor affects the rate and amount of absorbed water. The highest amount of absorbed water at 25°C was observed by using 0.6% cross-linking agent based on monomer mass. The temperature of absorbed water and its pH value are also essential factors that affect the rate and the amount of absorbed water and were investigated in this work. The highest amount of absorbed water was recorded at pH = 12 and at 60°C. The amount and the rate of water absorbed by Sodium Polyacrylate Hydrogel were also investigated at 25°C. The agriculture applications of hydrogel based on Sodium Polyacrylate were examined using Fenugreek seeds implanting.
文摘Novel aromatic-aliphatic poly(amide-imide)s containing chiral units in the main chain and hydroxyl benzamide units in the side chain have been obtained from the step-growth polymerization of 3,5-diamino-N-(4-hydroxyphenyl) benzamide (2) with different chiral diacid chlorides (la-le). Theoretical calculations were done by means of computational chemistry methods to narrate the stable conformation and orientation of each diacid chloride monomers under reaction conditions. These polymers were characterized by conventional techniques. The resulting polymers show good thermal stability. Other physical properties of polymers including crystallinity, inherent viscosity and morphological characteristics were also studied.
文摘Natural bioactive compounds from plants are of great importance in modern therapeutics,which are used to prepare antibiotics, growth supplements or some other therapeutics. Ltheanine is such a bioactive amide amino acid presented in different plants and fungi,especially in tea. Theanine has influential effects on lifestyle associated diseases, such as diabetes, cardiovascular disorders, hypertension, stress relief, tumor suppression,menstruation and liver injury. This amino acid can maintain normal sleep and improve memory function and nullify effect of the neurotoxins. The rate of bioavailability and its medium of ingestion in the body is one of the great concerns for its additional antioxidant properties. Pharmacokinetics of the bioactive compound and its mode of action are described herewith. The biosynthesis and industrial synthesis are also reviewed to promote accelerated production of this bioactive compound in the pharmaceutical industries.
文摘A new wo-armed?acyclic diamide Ia 2, 6-bis(1-ethanecarbozamido-2-amino)pyridine, and a new series of aromatic aldehyde schiff bases containing pyridine ring and amide bridge, IIa-f, were prepared. The compounds were characterized by elemental analysis, IR, 1HNMR and MS. The bioactivity half inhibitory concentration C1/2 is given.
基金Natural Science Foundation of Liaoning Province of China (No.20042009)Science and Technology Foundation of Shenyang City of China(No.20050785)
文摘Ursolic acid was modified at C3 and C28 position to obtain fourteen derivatives including twelve novel compounds, and their chemical structures were characterized by IR, ^1H NMR and MS. Cell growth inhibitory effects of the derivatives against Hela cell were evaluated by MTT assay. All these derivatives were found to have stronger cell growth inhibitory than their parent compound, ursolic acid. The derivatives with a substituted acetyl group at C3 hydroxyl group show better activities than those with an unsubstituted hydroxyl group.
文摘The development of economic and environmentally friendly extractants to recover cobalt metal is required due to the increasing demand for this metal.In this study,solvent extraction of Co(Ⅱ) from aqueous solution using a mixture of N,N'-carbonyl difatty amides(CDFAs) synthesised from palm oil as the extractant was carried out.The effects of various parameters such as acid,contact time,extractant concentration,metal ion concentration and stripping agent and the separation of Co(Ⅱ) from other metal ions such as Fe(Ⅱ),Ni(Ⅱ),Zn(Ⅲ) and Cd(Ⅱ) were investigated.It was found that the extraction of Co(Ⅱ) into the organic phase involved the formation of 1:1 complexes.Co(Ⅱ) was successfully separated from commonly associated metal ions such as Fe(Ⅱ),Ni(Ⅱ),Zn(Ⅲ) and Cd(Ⅱ).Co(Ⅱ) stripping from the loaded organic phase was studied in aqueous solution.These results are useful to recover Co(Ⅱ) from aqueous solution utilising(CDFAs) as an extractant.
基金supported by the National Natural Science Foundation of China (No. 21272265)the National High Technology Research and Development Program of China (No. 2011AA10A204)
文摘Based on the similarities in the conformation of VS008(N-(4-methylphenyl)-3-(tert-butyl)-1-(phenylmethyl)-1H-pyrazole-5-carboxamide) and BYIO6830(N'-(3,5-dimethylbenzoyl)-N'-tert-butyl-5-methyl-2,3-dihydro-l,4-benzodioxine-6-carbohydrazide) bound to the active site of the EcR subunit of the ecdysone receptor(EcR)-ultraspiracle protein(USP) heterodimeric receptor,a series of new pyrazole amide derivatives were designed and synthesized.Their structures were confirmed by IR,~1H NMR,^(13)C NMR and elemental analysis.Results from a preliminary bioassay revealed that two of the pyrazole derivatives exhibited promising insecticidal activity.Specifically,compounds 6e and 6i exhibited good activity against Helicoverpa armigera(cotton bollworm) at low concentration.Symptoms displayed by tebufenozide-treated H.armigera were identical with those displayed by its treated counterpart.6i showed the same poisoning symptoms as those of tebufenozide.In addition,results from molecular docking result indicated that the binding modes of 6e and 6i at the active site of the EcR subunit of the heterodimeric receptor were similar to that of the bound tebufenozide.
文摘(S)-(+)-2,2-dimethylcyclopropane carbox amide is a key intermediate of Cilastatin, an inhibitor of de- hydropeptidase-I. Its corresponding solid-liquid equilibrium data will provide essential support for industrial design and further theoretical studies. The solubilities of (S)-(+)-2,2-dimethylcyclopropane carbox amide in toluene, di- chloromethane, trichloromethane, ethyl acetate, ethanol and pure water at different temperature were measured us- ing the synthetic method by a laser monitoring observation technique. The solubility data were correlated with the modified Apelblat equation. The calculated values were good in agreement with the experimental values.
基金supported by the National Natural Science Foundation of China (No. 21272265)the National High Technology Research and Development Program of China (No.2011AA10A204)
文摘In order to discover highly active ecdysone analogs, a series of new substituted pyrazole amide derivatives were obtained using structure-guided optimization method and further screened for their insecticidal activities, in the basis of the core structures of the two active compounds N-(3-methoxyphenyl)-3-(tert-butyl)-1-phenyl-1H-pyrazole-5-carboxamide(6e) and N-(4-(tert-butyl)phenyl)-3-(tert-butyl)-1-phenyl-1H-pyrazole-5-carboxamide(6i), previously presented by us. The chemical structures of the title compounds were identified by spectral analyses. The preliminary bioassay results indicated that one among the synthesized pyrazole derivatives, compound 34, endowed with good activity against Mythimna Separata at 10 mg/L, which was equal to that displayed by the positive control tebufenozide. In addition, examples of molecular docking and molecular dynamics studies demonstrated that 34 may be the potential inhibitor to Ec R and its docking conformation was similar to that of tebufenozide. In addition, increasing the hydrophobic effect and considering the suitable bulk effect on pyrazole ring are beneficial to the inhibiting activity to Ec R and activity in vivo.
基金supported by the National Natural Science Foundation of China (Nos. 21472246 and 81321004)the Beijing Natural Science Foundation (No. 7152097)National Mega-Project for Innovation Drugs (No. 2012ZX09103101-037)
文摘A new series of 12-benzyl matrinic amide/ethanamide derivatives were synthesized from matrinine(1)and evaluated for their anti-HCV activity,taking compound 2 as the lead.SAR revealed that the introduction of a suitable substituent at the N’-end of matrinic amide might greatly enhance the potency.Among them,matrinic acid 17 and N’-substituted matrinic amides 18a-d exhibited promising potency with low micromolar EC50 values ranging from 1.03μmol/L to 7.54 μmol/L,and better therapeutic window with SI from 66 to 132.Moreover,compound 17 displayed an excellent PK and safety profile in vivo,demonstrating good drug-like characteristics.Thus,it has been selected for further investigation,with an advantage of decreased chances of inducing drug-resistance mutations.
文摘Two novel heterocyclic diamine monomers: 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl] (2H)phthalazin-1-one and 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)-3,5-dimethylphenyl](2H)phthalazin-1-one were successfully synthesized from readily available heterocyclic bisphenol-like monomers in two steps in high yield. A series of novel poly(aryl ether amide)s containing the phthalazinone moiety were successfully prepared by the direct polymerization of the novel diamines and aromatic dicarboxylic acids using triphenyl phosphite and pyridine as condensing agents.
文摘Four gemini cationic surfactants {N,N′-di[2-(lauryldimethylamino)acetyl]polymethylenediamine dichloride, LAA-s-LAA, s=2,3,4,6} were synthesized by using four bis(α-chloroacetamide)s and N,N-dimethyllaurylamine, respectively. The molecular structures were characterized by means of IR, ~ 1H NMR, \{~ ~13 C NMR\} and MS, and the behavior of their aqueous solutions was studied. The critical micell concentrations(CMC) of LAA-s-LAA were one order of magnitude lower than that of dodecyltrimethyl ammonium chloride(DTAC). With the change of the length of spacer chain(s), their CMC values change, and CMC reaches the top value at s=4.
基金the National Natural Science Foundation of China(No 20576026)State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology(No 200402)+2 种基金Science & Technology Office of Hebei Province(No 04213036)Foundation of HebeiUniversity of Science and Technology(No XL2006021)Environmental Engineering Key Subject of Hebei Province
文摘Amide ionic liquids (MLs)/L-proline synergistic catalyzed Mannich reactions of isovaleraldehyde, methyl ketones, and aromatic amines were carried out in moderate to high yields ( up to 96% ) and high stereo selectivities ( 〉99% e. e. ). The products were easily isolated by extraction; and the catalyst system was readily recycled at least thrice without significant loss of efficiency. The scope of the substrates was studied and the interpretation of the manifest improvement of the reaction rates and enantio-selectivity of the novel catalyst system was speculated.
基金Authors are thankful to Head of Department of Chemistry V.G.Vaze College,Mulund(E),Mumbai-81(MS),India and Head of Department of Organic Research Laboratory,S.C.S.College,Omerga-413 606(MS),India for providing the necessary laboratory facilities
文摘The coupling reaction of phenylurea with different functionalized aryl halides in the presence of air stable CuI,N,N-dimethylethylenediamine as a ligand,and K_3PO_4 as a base gives symmetrical and unsymmetrical diarylureas in relatively high yields.This method is milder than the palladium catalyzed arylation and avoids the use of toxic phosphine ligands.
文摘Five DTPA bis(amide)s have been synthesized and characterized by means of 1 H NMR , FT IR and elemental analyses. The stability constants of their Gd 3+ complexes have been measured using a simple spectrophotometric method. The results show that the complexing properties of the ligands in comparison with those of DTPA are affected by converting two carboxyl groups to amide groups. The relaxation studies have shown that the relaxivity of the chelates is similar to that of Gd DTPA, indicating that in solution all the chelates have one water molecule directly coordinated to the metal ion. Only one water molecule in inner coordination sphere suggests the coordination of the carboxamide oxygen to gadolinium ion, which agrees with the FT IR results.