A facile one-pot synthesis of 3,4,5-substituted furan-2（5H）-one derivatives from a three-component reaction of aniline derivatives, dialkylacetylenedicarboxylates and aromatic aldehydes under mild conditions using t...A facile one-pot synthesis of 3,4,5-substituted furan-2（5H）-one derivatives from a three-component reaction of aniline derivatives, dialkylacetylenedicarboxylates and aromatic aldehydes under mild conditions using tetra-n-butylammonium bisulfate as a catalyst has been developed.展开更多
Sulfonylurea herbicides have been widely used because of their low application rates, good crop sdeetivities and low mammalian toxicities. However, some sulfonylureas might persist unfavourably in the environment with...Sulfonylurea herbicides have been widely used because of their low application rates, good crop sdeetivities and low mammalian toxicities. However, some sulfonylureas might persist unfavourably in the environment with residual problems. In order to look for ecologically safer and environmentally benign sulfonylureas, and on keeping the pyrimidine ring being monosubstitated, 15 novd C5-monosubstituted benzenesulfonylurea compounds were synthesized. The structures of all the compounds synthesized were confirmed by demental analysis and ^1H NMR. Preliminary herbicidal activities of these new sulfonylurea compounds were determined by ALS screening （ in vitro） and pot bioassay experiments（ in vivo）. The herbicidal results show that some novel sulfonylureas are comparable to commercial Foramsulfuron and Monosulfuron.展开更多
Four novel 5-substituted pyridine-2(1H)-one derivatives were designed and synthesized by using addition-elimination reactions.The structures of these novelly synthesized compounds were verified by ~1H NMR,ESI-MS and s...Four novel 5-substituted pyridine-2(1H)-one derivatives were designed and synthesized by using addition-elimination reactions.The structures of these novelly synthesized compounds were verified by ~1H NMR,ESI-MS and single crystal X-ray diffraction.Furthermore,all four compounds(most notably compound 7a) were found to be highly efficient against hepatitis B virus (HBV) in cultured HepG2 2.2.15 cell,making them promising drug candidates for potential bioactive molecule against hepatitis B.展开更多
We have developed simple,cost effective and environmentally benign protocol for the synthesis of 5-substituted 1H-tetrazoles via[2,3]cycloaddition reaction from organic nitriles and sodium azide in glycerol under cata...We have developed simple,cost effective and environmentally benign protocol for the synthesis of 5-substituted 1H-tetrazoles via[2,3]cycloaddition reaction from organic nitriles and sodium azide in glycerol under catalyst free condition.The corresponding 5-substituted 1H-tetrazoles were obtained with good to excellent yields（68-95%）.展开更多
Zinc chloride is an efficient and safe catalyst in the [3 ＋ 2] cycloaddition reaction of organic nitriles with sodium azide in solventless condition. The corresponding 5-substituted ^1H tetrazoles were obtained under...Zinc chloride is an efficient and safe catalyst in the [3 ＋ 2] cycloaddition reaction of organic nitriles with sodium azide in solventless condition. The corresponding 5-substituted ^1H tetrazoles were obtained under mild conditions. This method can overcome disadvantages such as： the use of toxic metals and expensive reagents, drastic reaction conditions, water sensitivity and the presence of dangerous hydrazoic acid.展开更多
5-Substituted hexahydro-1H-1,4-diazepine analogues were synthesized starting from N,N'-dibenzyl-1, 2-ethylenediamine and methyl 2, 4-dibromide butyrate through nucleophilic substitution, reduction, chlorination, d...5-Substituted hexahydro-1H-1,4-diazepine analogues were synthesized starting from N,N'-dibenzyl-1, 2-ethylenediamine and methyl 2, 4-dibromide butyrate through nucleophilic substitution, reduction, chlorination, debenzylation and amidation. Bioactivity tests showed that 9a had the highest agonist activity.展开更多
Additions of diethyl phosphite to α-nitroalkenes followed by the introduction of trimethylchlorosilane and an activated alkene, gave the corresponding title compounds via regioselective 1,3-dipolar cycloaddition in m...Additions of diethyl phosphite to α-nitroalkenes followed by the introduction of trimethylchlorosilane and an activated alkene, gave the corresponding title compounds via regioselective 1,3-dipolar cycloaddition in moderate yield.展开更多
The synthesis of a new series of 3-（5-substituted benzimidazol-2-yl）-5-arylisoxazolines （6a-h） was achieved in excellent yields by the condensation of 1-（1H-benzimidazol-2-yl）-3-（substituted phenyl）prop-2-en-l...The synthesis of a new series of 3-（5-substituted benzimidazol-2-yl）-5-arylisoxazolines （6a-h） was achieved in excellent yields by the condensation of 1-（1H-benzimidazol-2-yl）-3-（substituted phenyl）prop-2-en-l-ones （5a-h） with hydroxylamine at room temperature. These 1-（1H-benzimidazol-2-yl）-3-（subsfituted phenyl）prop-2-en-l-ones （Sa-h） were obtained by the condensation of 2-acetyl benzimidazoles （4a-d） with different aromatic aldehydes, which in turn were obtained by the oxidation of 2-（α- hydroxy）ethyl benzimidazoles （3a-d） prepared by the reaction of o-phenylenediamines （lad） with ot-hydroxy propiohic acid 2. The synthesized compounds were characterized by their IR, ^1H NMR and MS analyses. These compounds were screened for their antibacterial and antifungal activity by standard methods and found some of them active.展开更多
The synthesis of 1,3,5-substituted-1,2,4-triazoles from α-imino-3-pyridine formic acid,acetamidine and anisole hydrazine as a model reaction in this paper and the synthesis mechanism of 1,3,5-substituted-1,2,4-triazo...The synthesis of 1,3,5-substituted-1,2,4-triazoles from α-imino-3-pyridine formic acid,acetamidine and anisole hydrazine as a model reaction in this paper and the synthesis mechanism of 1,3,5-substituted-1,2,4-triazole compounds from carboxylic acids,amidines and hydrazines have been first investigated with the B3 LYP/6-311＋＋G＊＊ method.According to the potential energy profile,it can be predicted that the course of the reaction consists of five reactions containing six elementary reactions.The α-imino-3-pyridine formic acid and acetamidine form first an intermediate product through a dehydration reaction; the intermediate product further combines with hydrogen ion to form a positive ion; the positive ion reacts with anisole hydrazine by a dehydration reaction to form another positive ion; then,followed by two isomerization reactions,the final reaction with the acetate ion（Ac-） produces the final product.The research results reveal the laws of synthesis reaction of 1,3,5-substituted-1,2,4-triazoles by the carboxylic acids,amidines,hydrazines and their derivatives on theoretical level.It provides the systemic theoretical basis for the synthesis,development and application of 1,3,5-substituted-1,2,4-triazole compounds.展开更多
Eight new Schiff bases of 5-nitro and 5-bromo-substituted 1,10-phenanthroline-2,9-dicarboxaldehydes with sulfur-containing amines, thiosemicarbazide, S-alkyl/aryl dithiocarbazates and 2-mercaptoaniline have been synth...Eight new Schiff bases of 5-nitro and 5-bromo-substituted 1,10-phenanthroline-2,9-dicarboxaldehydes with sulfur-containing amines, thiosemicarbazide, S-alkyl/aryl dithiocarbazates and 2-mercaptoaniline have been synthesized and characterized by a variety of spectroscopic methods. The condensation reactions of the dialdehydes with the amines were carried out both in the presence and absence of conc. sulfuric acid. A significant increase in yield of the Schiff bases was observed when the reactions were carried out in the presence of sulfuric acid.展开更多
Schiff bases are known to possess anticancer, antibacterial, antifungal, antitubercular, anti-inflammatory, antimicrobial and antimalarial properties. In this paper antibacterial studies against variety of plants and ...Schiff bases are known to possess anticancer, antibacterial, antifungal, antitubercular, anti-inflammatory, antimicrobial and antimalarial properties. In this paper antibacterial studies against variety of plants and human pathogenic bacteria with eight newly synthesized Schiff bases and several intermediate silyl compounds have been reported. The antibacterial activities of the synthesized compounds were primarily determined by paper disc diffusion method. The minimum inhibitory concentration (MIC) of each compound was also determined by tube dilution process. Seven different human pathogenic bacteria and eighteen different plant pathogenic bacteria were used for the antibacterial activity studies. While all synthesized compounds have shown significant antibacterial activity, one intermediate silyl compound has shown remarkably high antibacterial property. 5-substituted derivatives have shown relatively higher activity than non-substituted compounds. Polar substituent which increases hydrophilicity may have a positive impact on the antibacterial property.展开更多
By using 1-methyl-2-formyl-5 -Y-substituted pyrrole (4-nitrophenyl)hydrazones as a model for nitrogen-containing heterocyclic aromatic compounds, the emission wavelength [lambda(max(em))] values df their fluorescence ...By using 1-methyl-2-formyl-5 -Y-substituted pyrrole (4-nitrophenyl)hydrazones as a model for nitrogen-containing heterocyclic aromatic compounds, the emission wavelength [lambda(max(em))] values df their fluorescence spectra have been measured. Correlation results show that the Delta E-em values are mainly affected by polar effects, but spin-delocalizatin effects also exist.展开更多
A visible light-promoted fast photochemical Wolff rearrangement was developed toward synthesis ofα-substituted amides in continuous flow with the use of a photochemical oscillatory flow reactor(POFR).The control expe...A visible light-promoted fast photochemical Wolff rearrangement was developed toward synthesis ofα-substituted amides in continuous flow with the use of a photochemical oscillatory flow reactor(POFR).The control experiment indicates that a fast process of the Wolff rearrangement(<40 s)is involved.Notably,this protocol does not require excess use of any reactants,and the resultingα-substituted amides could be isolated by recrystallization in good to excellent yields.展开更多
Temperature plays a crucial role in regulating polymorphism in supramolecular polymers.Understanding the mechanism behind temperature-dependent supramolecular polymorphism is crucial as it provides an opportunity to t...Temperature plays a crucial role in regulating polymorphism in supramolecular polymers.Understanding the mechanism behind temperature-dependent supramolecular polymorphism is crucial as it provides an opportunity to tailor polymorphs for specific properties and applications.In this study,we present our findings on a naphthalimide-substituted benzene-1,3,5-tricarboxamide derivative,R-Nap-1,which exhibits two distinct polymerization pathways at varying temperatures.At 313 K,polymerization results in the formation of an M-chiral polymorph,whereas at 253 K,a P-chiral polymorph is formed.Both polymorphs are notably stable,remaining unchanged for over six months under ambient conditions.Theoretical calculations and experimental investigations allowed us to elucidate the mechanisms underlying these polymorphic transformations.The formation of the M-chiral polymorph at 313 K is attributed to the nucleation and growth of R-Nap-1 monomers once their concentration surpasses a critical threshold.Conversely,at lower temperatures(e.g.,253 K),the monomers undergo facile transformation into dimers due to a lower energy barrier and reduced Gibbs energy compared to the monomeric state.Subsequently,these dimers undergo nucleation-elongation to form the P-chiral polymorph when their concentration exceeds the critical polymerization concentration.The stability and lack of interconversion between the two polymorphs can be attributed to their close thermodynamic stabilities,as evidenced by variable-temperature CD spectra and DFT calculations.These findings highlight the importance of accurate temperature control in supramolecular polymerization processes,making a significant contribution to the understanding of supramolecular polymorphism,thus advancing the field of supramolecular chemistry.展开更多
A three-dimensional quantitative structure-activity relationship(3 D-QSAR) study was conducted to analyze the A1 AR density(Bmax) of 56 3-aroyl-5-substituted thiophene derivatives(ASTDs) in human A1 Chinese hamster ov...A three-dimensional quantitative structure-activity relationship(3 D-QSAR) study was conducted to analyze the A1 AR density(Bmax) of 56 3-aroyl-5-substituted thiophene derivatives(ASTDs) in human A1 Chinese hamster ovary(hA1 CHO) membranes by the comparative molecular field analysis(CoMFA) method. A training set of 45 compounds was used to establish the predictive model, which was verified by the test set of 17 compounds containing template molecule and 5 newly designed molecules. The cross-validation(R2 cv) and non-cross-validation(R2) coefficients of the training set were 0.655 and 0.959, respectively. The model was used to predict the activities of the compounds of the training and test sets, and the results indicated that the models had strong stability and good prediction ability. According to model analysis, the contribution of steric and electrostatic fields was 51.4% and 48.6%, respectively. Based on the 3 D contour maps, five excellent ASTDs agonists were designed, which need to be further verified by biomedical experiments.展开更多
基金fnancial support from the Research Council of the University of Sistan and Baluchestan
文摘A facile one-pot synthesis of 3,4,5-substituted furan-2（5H）-one derivatives from a three-component reaction of aniline derivatives, dialkylacetylenedicarboxylates and aromatic aldehydes under mild conditions using tetra-n-butylammonium bisulfate as a catalyst has been developed.
基金Supported by the National Key Basic Research Program of China(No.2003CB114406)the National Natural Science Foundation Key Project of China(No.20432010).
文摘Sulfonylurea herbicides have been widely used because of their low application rates, good crop sdeetivities and low mammalian toxicities. However, some sulfonylureas might persist unfavourably in the environment with residual problems. In order to look for ecologically safer and environmentally benign sulfonylureas, and on keeping the pyrimidine ring being monosubstitated, 15 novd C5-monosubstituted benzenesulfonylurea compounds were synthesized. The structures of all the compounds synthesized were confirmed by demental analysis and ^1H NMR. Preliminary herbicidal activities of these new sulfonylurea compounds were determined by ALS screening （ in vitro） and pot bioassay experiments（ in vivo）. The herbicidal results show that some novel sulfonylureas are comparable to commercial Foramsulfuron and Monosulfuron.
文摘Four novel 5-substituted pyridine-2(1H)-one derivatives were designed and synthesized by using addition-elimination reactions.The structures of these novelly synthesized compounds were verified by ~1H NMR,ESI-MS and single crystal X-ray diffraction.Furthermore,all four compounds(most notably compound 7a) were found to be highly efficient against hepatitis B virus (HBV) in cultured HepG2 2.2.15 cell,making them promising drug candidates for potential bioactive molecule against hepatitis B.
基金support from Department of Atomic Energy-Board of Research in Nuclear Sciences(DAE-BRNS)(No2009/37/39/BRNS/2268)
文摘We have developed simple,cost effective and environmentally benign protocol for the synthesis of 5-substituted 1H-tetrazoles via[2,3]cycloaddition reaction from organic nitriles and sodium azide in glycerol under catalyst free condition.The corresponding 5-substituted 1H-tetrazoles were obtained with good to excellent yields（68-95%）.
基金Research Council of K.N.Toosi University of Technology for partial financial support of this work
文摘Zinc chloride is an efficient and safe catalyst in the [3 ＋ 2] cycloaddition reaction of organic nitriles with sodium azide in solventless condition. The corresponding 5-substituted ^1H tetrazoles were obtained under mild conditions. This method can overcome disadvantages such as： the use of toxic metals and expensive reagents, drastic reaction conditions, water sensitivity and the presence of dangerous hydrazoic acid.
文摘5-Substituted hexahydro-1H-1,4-diazepine analogues were synthesized starting from N,N'-dibenzyl-1, 2-ethylenediamine and methyl 2, 4-dibromide butyrate through nucleophilic substitution, reduction, chlorination, debenzylation and amidation. Bioactivity tests showed that 9a had the highest agonist activity.
文摘Additions of diethyl phosphite to α-nitroalkenes followed by the introduction of trimethylchlorosilane and an activated alkene, gave the corresponding title compounds via regioselective 1,3-dipolar cycloaddition in moderate yield.
文摘The synthesis of a new series of 3-（5-substituted benzimidazol-2-yl）-5-arylisoxazolines （6a-h） was achieved in excellent yields by the condensation of 1-（1H-benzimidazol-2-yl）-3-（substituted phenyl）prop-2-en-l-ones （5a-h） with hydroxylamine at room temperature. These 1-（1H-benzimidazol-2-yl）-3-（subsfituted phenyl）prop-2-en-l-ones （Sa-h） were obtained by the condensation of 2-acetyl benzimidazoles （4a-d） with different aromatic aldehydes, which in turn were obtained by the oxidation of 2-（α- hydroxy）ethyl benzimidazoles （3a-d） prepared by the reaction of o-phenylenediamines （lad） with ot-hydroxy propiohic acid 2. The synthesized compounds were characterized by their IR, ^1H NMR and MS analyses. These compounds were screened for their antibacterial and antifungal activity by standard methods and found some of them active.
基金supported by the National Natural Science Foundation of China(No.51102114)
文摘The synthesis of 1,3,5-substituted-1,2,4-triazoles from α-imino-3-pyridine formic acid,acetamidine and anisole hydrazine as a model reaction in this paper and the synthesis mechanism of 1,3,5-substituted-1,2,4-triazole compounds from carboxylic acids,amidines and hydrazines have been first investigated with the B3 LYP/6-311＋＋G＊＊ method.According to the potential energy profile,it can be predicted that the course of the reaction consists of five reactions containing six elementary reactions.The α-imino-3-pyridine formic acid and acetamidine form first an intermediate product through a dehydration reaction; the intermediate product further combines with hydrogen ion to form a positive ion; the positive ion reacts with anisole hydrazine by a dehydration reaction to form another positive ion; then,followed by two isomerization reactions,the final reaction with the acetate ion（Ac-） produces the final product.The research results reveal the laws of synthesis reaction of 1,3,5-substituted-1,2,4-triazoles by the carboxylic acids,amidines,hydrazines and their derivatives on theoretical level.It provides the systemic theoretical basis for the synthesis,development and application of 1,3,5-substituted-1,2,4-triazole compounds.
文摘Eight new Schiff bases of 5-nitro and 5-bromo-substituted 1,10-phenanthroline-2,9-dicarboxaldehydes with sulfur-containing amines, thiosemicarbazide, S-alkyl/aryl dithiocarbazates and 2-mercaptoaniline have been synthesized and characterized by a variety of spectroscopic methods. The condensation reactions of the dialdehydes with the amines were carried out both in the presence and absence of conc. sulfuric acid. A significant increase in yield of the Schiff bases was observed when the reactions were carried out in the presence of sulfuric acid.
文摘Schiff bases are known to possess anticancer, antibacterial, antifungal, antitubercular, anti-inflammatory, antimicrobial and antimalarial properties. In this paper antibacterial studies against variety of plants and human pathogenic bacteria with eight newly synthesized Schiff bases and several intermediate silyl compounds have been reported. The antibacterial activities of the synthesized compounds were primarily determined by paper disc diffusion method. The minimum inhibitory concentration (MIC) of each compound was also determined by tube dilution process. Seven different human pathogenic bacteria and eighteen different plant pathogenic bacteria were used for the antibacterial activity studies. While all synthesized compounds have shown significant antibacterial activity, one intermediate silyl compound has shown remarkably high antibacterial property. 5-substituted derivatives have shown relatively higher activity than non-substituted compounds. Polar substituent which increases hydrophilicity may have a positive impact on the antibacterial property.
文摘By using 1-methyl-2-formyl-5 -Y-substituted pyrrole (4-nitrophenyl)hydrazones as a model for nitrogen-containing heterocyclic aromatic compounds, the emission wavelength [lambda(max(em))] values df their fluorescence spectra have been measured. Correlation results show that the Delta E-em values are mainly affected by polar effects, but spin-delocalizatin effects also exist.
基金financial support from the National Natural Science Foundation of China(No.22208279)Financial support from the Fuzhou University(No.0041/511095)。
文摘A visible light-promoted fast photochemical Wolff rearrangement was developed toward synthesis ofα-substituted amides in continuous flow with the use of a photochemical oscillatory flow reactor(POFR).The control experiment indicates that a fast process of the Wolff rearrangement(<40 s)is involved.Notably,this protocol does not require excess use of any reactants,and the resultingα-substituted amides could be isolated by recrystallization in good to excellent yields.
基金supported by the Chinese Academy of Sciences CAS Project for Young Scientists in Basic Research(No.YSBR-027)。
文摘Temperature plays a crucial role in regulating polymorphism in supramolecular polymers.Understanding the mechanism behind temperature-dependent supramolecular polymorphism is crucial as it provides an opportunity to tailor polymorphs for specific properties and applications.In this study,we present our findings on a naphthalimide-substituted benzene-1,3,5-tricarboxamide derivative,R-Nap-1,which exhibits two distinct polymerization pathways at varying temperatures.At 313 K,polymerization results in the formation of an M-chiral polymorph,whereas at 253 K,a P-chiral polymorph is formed.Both polymorphs are notably stable,remaining unchanged for over six months under ambient conditions.Theoretical calculations and experimental investigations allowed us to elucidate the mechanisms underlying these polymorphic transformations.The formation of the M-chiral polymorph at 313 K is attributed to the nucleation and growth of R-Nap-1 monomers once their concentration surpasses a critical threshold.Conversely,at lower temperatures(e.g.,253 K),the monomers undergo facile transformation into dimers due to a lower energy barrier and reduced Gibbs energy compared to the monomeric state.Subsequently,these dimers undergo nucleation-elongation to form the P-chiral polymorph when their concentration exceeds the critical polymerization concentration.The stability and lack of interconversion between the two polymorphs can be attributed to their close thermodynamic stabilities,as evidenced by variable-temperature CD spectra and DFT calculations.These findings highlight the importance of accurate temperature control in supramolecular polymerization processes,making a significant contribution to the understanding of supramolecular polymorphism,thus advancing the field of supramolecular chemistry.
基金supported by the National Natural Science Foundation of China (21676292,21075138)special fund of State Key Laboratory of Structure Chemistry (2016028)。
文摘A three-dimensional quantitative structure-activity relationship(3 D-QSAR) study was conducted to analyze the A1 AR density(Bmax) of 56 3-aroyl-5-substituted thiophene derivatives(ASTDs) in human A1 Chinese hamster ovary(hA1 CHO) membranes by the comparative molecular field analysis(CoMFA) method. A training set of 45 compounds was used to establish the predictive model, which was verified by the test set of 17 compounds containing template molecule and 5 newly designed molecules. The cross-validation(R2 cv) and non-cross-validation(R2) coefficients of the training set were 0.655 and 0.959, respectively. The model was used to predict the activities of the compounds of the training and test sets, and the results indicated that the models had strong stability and good prediction ability. According to model analysis, the contribution of steric and electrostatic fields was 51.4% and 48.6%, respectively. Based on the 3 D contour maps, five excellent ASTDs agonists were designed, which need to be further verified by biomedical experiments.
