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2018 Volume 38 Issue 4
2018, 38(4): 719-737
doi: 10.6023/cjoc201710002
Abstract:
The sulfoximine derivatives are widely known for their potent biological and medicinal activities. Recently, due to the transition-metal catalysis, great advancements have been achieved in the synthesis of sulfoximine derivatives. Utilizing free NH-sulfoximines as the starting materials, various the direct N-H functionalizations can be accomplished, such as alkynylation, alkenylation, alkylation, arylation, etc. In addition, the ortho arene C(sp2)-H activation can also be obtained through C-H activation reaction with the assistance of S=NH as intramolecular directing groups, thus giving varies (hetero)aromatic molecules. N-H and C-H functionalization reactions of sulfoximines were summarized, and the mechanisms of some novel model reactions are also briefly discussed.
The sulfoximine derivatives are widely known for their potent biological and medicinal activities. Recently, due to the transition-metal catalysis, great advancements have been achieved in the synthesis of sulfoximine derivatives. Utilizing free NH-sulfoximines as the starting materials, various the direct N-H functionalizations can be accomplished, such as alkynylation, alkenylation, alkylation, arylation, etc. In addition, the ortho arene C(sp2)-H activation can also be obtained through C-H activation reaction with the assistance of S=NH as intramolecular directing groups, thus giving varies (hetero)aromatic molecules. N-H and C-H functionalization reactions of sulfoximines were summarized, and the mechanisms of some novel model reactions are also briefly discussed.
2018, 38(4): 738-751
doi: 10.6023/cjoc201709045
Abstract:
Aromatic boronic acids and esters are essential intermediates and have been widely used in biology, medicine and material science. In this paper, the resent progress on their synthesis is summarized, especially Pd-catalyzed borylation of aryl chlorides with steric hindrance substrates, other metal (Ni, Cu, Fe, Zn, Rh, Co)-catalyzed borylation, metal-free borylation, and photoinduced borylation.
Aromatic boronic acids and esters are essential intermediates and have been widely used in biology, medicine and material science. In this paper, the resent progress on their synthesis is summarized, especially Pd-catalyzed borylation of aryl chlorides with steric hindrance substrates, other metal (Ni, Cu, Fe, Zn, Rh, Co)-catalyzed borylation, metal-free borylation, and photoinduced borylation.
2018, 38(4): 752-759
doi: 10.6023/cjoc201710001
Abstract:
The construction of C-N bond is the foundation of organic synthesis, which plays a significant role in the synthesis of drug molecules, natural products and functional materials. Accordingly, it has been received much attention. Recently, the remarkable progress has been made in construction of C-N bond by using n-Bu4NI/t-BuOOH under transition-metal-free condition. Due to the relatively mild reaction condition and excellent selectivity, it provides an economy and efficient approach to construct C-N bond. In this review, the recent advances in this area are summarized on the basis of different nitrogen sources.
The construction of C-N bond is the foundation of organic synthesis, which plays a significant role in the synthesis of drug molecules, natural products and functional materials. Accordingly, it has been received much attention. Recently, the remarkable progress has been made in construction of C-N bond by using n-Bu4NI/t-BuOOH under transition-metal-free condition. Due to the relatively mild reaction condition and excellent selectivity, it provides an economy and efficient approach to construct C-N bond. In this review, the recent advances in this area are summarized on the basis of different nitrogen sources.
2018, 38(4): 760-774
doi: 10.6023/cjoc201708048
Abstract:
Methods for optical detection or sensing of L-cysteine with high selectivity and sensitivity have attracted increasing interest recently due to the potential association of L-cysteine to the fields of pathophysiology and clinical medicine. Recent advances since 2010 on reaction-based small molecule sensors as well as sensing ensembles constructed by metal complex and nanomaterials for optical sensing of L-cysteine were highlighted. The future advances in this field were also predicted and given at the end of this review.
Methods for optical detection or sensing of L-cysteine with high selectivity and sensitivity have attracted increasing interest recently due to the potential association of L-cysteine to the fields of pathophysiology and clinical medicine. Recent advances since 2010 on reaction-based small molecule sensors as well as sensing ensembles constructed by metal complex and nanomaterials for optical sensing of L-cysteine were highlighted. The future advances in this field were also predicted and given at the end of this review.
2018, 38(4): 775-790
doi: 10.6023/cjoc201709044
Abstract:
3-Substituted imidazo[1, 2-a] pyridines are important N-fused heterocycles with extensive application value in medicine, materials and other fields. C(3)-H bond functionalization strategy was a simple and effective way to build 3-substituted imidazo[1, 2-a] pyridines. The recent advances of the access to 3-substituted imidazo[1, 2-a] pyridines according to the type of bonding (C-C, C-S/Se, C-N/P) on C-3 position are briefly summarized, and a prospect for the future development is made.
3-Substituted imidazo[1, 2-a] pyridines are important N-fused heterocycles with extensive application value in medicine, materials and other fields. C(3)-H bond functionalization strategy was a simple and effective way to build 3-substituted imidazo[1, 2-a] pyridines. The recent advances of the access to 3-substituted imidazo[1, 2-a] pyridines according to the type of bonding (C-C, C-S/Se, C-N/P) on C-3 position are briefly summarized, and a prospect for the future development is made.
2018, 38(4): 791-801
doi: 10.6023/cjoc201709025
Abstract:
Nitrogen heterocyclic compounds can be found in various natural products, pharmaceutical chemistry and material chemistry. Due to azide group linked to olefins, α-aryl vinyl azide has unique properties, which can act as electrophilic reagents, nucleophilic reagent, or radical acceptor. Diverse reaction pathways of α-aryl vinyl azide provide great opportunities to generate highly reactive intermediates with unusual or unconventional reactivities, making it possible to develop novel reaction. Recently, more and more synthetic chemists used α-aryl vinyl azide as a key three atoms synthon for the construction of diverse structurally complex N-heterocyclic compounds. This review will introduce systematically the reactivities of α-aryl vinyl azide and the developments of the recent application of α-aryl vinyl azide in nitrogen heterocycle synthesis, including mechanism, reaction characteristics and application study, thus it may be helpful for the research on nitrogen heterocycle synthesis.
Nitrogen heterocyclic compounds can be found in various natural products, pharmaceutical chemistry and material chemistry. Due to azide group linked to olefins, α-aryl vinyl azide has unique properties, which can act as electrophilic reagents, nucleophilic reagent, or radical acceptor. Diverse reaction pathways of α-aryl vinyl azide provide great opportunities to generate highly reactive intermediates with unusual or unconventional reactivities, making it possible to develop novel reaction. Recently, more and more synthetic chemists used α-aryl vinyl azide as a key three atoms synthon for the construction of diverse structurally complex N-heterocyclic compounds. This review will introduce systematically the reactivities of α-aryl vinyl azide and the developments of the recent application of α-aryl vinyl azide in nitrogen heterocycle synthesis, including mechanism, reaction characteristics and application study, thus it may be helpful for the research on nitrogen heterocycle synthesis.
2018, 38(4): 802-811
doi: 10.6023/cjoc201709041
Abstract:
Organoaluminum compounds are excellent nucleophiles for organic reactions because of their high reactivities, the high Lewis acidity of the aluminum center, and their low toxicities. Therefore, organoalanes are widely applied in cross-coupling reactions. In this paper, recent research results about the organoaluminum reagents applied in cross-coupling reactions catalyzed by palladium are reviewed, involving various reaction systems.
Organoaluminum compounds are excellent nucleophiles for organic reactions because of their high reactivities, the high Lewis acidity of the aluminum center, and their low toxicities. Therefore, organoalanes are widely applied in cross-coupling reactions. In this paper, recent research results about the organoaluminum reagents applied in cross-coupling reactions catalyzed by palladium are reviewed, involving various reaction systems.
2018, 38(4): 812-824
doi: 10.6023/cjoc201708019
Abstract:
In 1967, Fujiwara and Moritani reported a type of cross coupling reaction where an aromatic C-H bond is directly coupled to an olefinic C-H bond, generating a new C-C bond in the first time. This reaction is performed in the presence of a transition metal, and typically palladium. In the next few decades, palladium-catalyzed oxidative coupling reactions have become an important method in organic synthesis, and a lot of achievements in scientific research have emerged in the relevant areas. The progress in oxidative coupling reaction of olefins, alkynes and aromatic hydrocarbons catalyzed by palladium is reviewed.
In 1967, Fujiwara and Moritani reported a type of cross coupling reaction where an aromatic C-H bond is directly coupled to an olefinic C-H bond, generating a new C-C bond in the first time. This reaction is performed in the presence of a transition metal, and typically palladium. In the next few decades, palladium-catalyzed oxidative coupling reactions have become an important method in organic synthesis, and a lot of achievements in scientific research have emerged in the relevant areas. The progress in oxidative coupling reaction of olefins, alkynes and aromatic hydrocarbons catalyzed by palladium is reviewed.
2018, 38(4): 825-831
doi: 10.6023/cjoc201703037
Abstract:
The theoretical study is presented for the Michael addition reaction between trans-1-nitro-2-phenylethylene and 2-methylpropionaldehyde catalyzed by (9S)-9-amino-6'-methoxy-10, 11-dihydrocinchonan (9-epi-DHQDA) and benzoic acid. All structures, including the reactants, intermediates, transition states and products were optimized. Transition states have been confirmed by the corresponding vibration analysis and intrinsic reaction coordinate (IRC). In addition, nature bond orbital (NBO) and atoms in molecules (AIM) theories have been used to analyze orbital interactions and bond natures. Calculations indicate that the benzoic acid might undergo a proton step to the 9-epi-DHQDA to produce the iminium intermediate. Then the iminium serves as a reactive acceptor to participate in the subsequent nucleophilic addition. Next, a proton transfer process from the tertiary amine to nitronate carbon is found to be rate-determining step, and the enantioselectivity of the catalyzed Michael reaction is also controlled by this step. Finally, one water molecule participates in hydrolysis and C=O bond formation, and results in the formation of product and recovery of catalyst.
The theoretical study is presented for the Michael addition reaction between trans-1-nitro-2-phenylethylene and 2-methylpropionaldehyde catalyzed by (9S)-9-amino-6'-methoxy-10, 11-dihydrocinchonan (9-epi-DHQDA) and benzoic acid. All structures, including the reactants, intermediates, transition states and products were optimized. Transition states have been confirmed by the corresponding vibration analysis and intrinsic reaction coordinate (IRC). In addition, nature bond orbital (NBO) and atoms in molecules (AIM) theories have been used to analyze orbital interactions and bond natures. Calculations indicate that the benzoic acid might undergo a proton step to the 9-epi-DHQDA to produce the iminium intermediate. Then the iminium serves as a reactive acceptor to participate in the subsequent nucleophilic addition. Next, a proton transfer process from the tertiary amine to nitronate carbon is found to be rate-determining step, and the enantioselectivity of the catalyzed Michael reaction is also controlled by this step. Finally, one water molecule participates in hydrolysis and C=O bond formation, and results in the formation of product and recovery of catalyst.
2018, 38(4): 832-839
doi: 10.6023/cjoc201710012
Abstract:
MIL-101 was synthesized by hydrothermal method, and Pd/MIL-101 catalyst was prepared by supporting palladium nanoparticles on metal-organic frameworks MIL-101. The microstructure and features of the catalyst were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), inductive coupled plasma (ICP), high resolution transmission electron microscopy (HRTEM) and N2 adsorption, respectively. The experimental results reveal that the Pd nanoparticles on Pd/MIL-101 range from 1.5 nm to 2.5 nm, and the content of Pd nanoparticles is 1.5%. The catalytic experiments show that Pd/MIL-101 has a high catalytic activity for the C2 arylation of benzofuran. For less active aryl bromides, the reaction gave moderate yields. Moreover, the catalyst could be recycled many times. After 5 runs of catalysis, the catalyst can still maintain high reactivity. This strategy provides a simple, effective method for the synthesis of benzofuran derivatives.
MIL-101 was synthesized by hydrothermal method, and Pd/MIL-101 catalyst was prepared by supporting palladium nanoparticles on metal-organic frameworks MIL-101. The microstructure and features of the catalyst were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), inductive coupled plasma (ICP), high resolution transmission electron microscopy (HRTEM) and N2 adsorption, respectively. The experimental results reveal that the Pd nanoparticles on Pd/MIL-101 range from 1.5 nm to 2.5 nm, and the content of Pd nanoparticles is 1.5%. The catalytic experiments show that Pd/MIL-101 has a high catalytic activity for the C2 arylation of benzofuran. For less active aryl bromides, the reaction gave moderate yields. Moreover, the catalyst could be recycled many times. After 5 runs of catalysis, the catalyst can still maintain high reactivity. This strategy provides a simple, effective method for the synthesis of benzofuran derivatives.
Microwave-Assisted Synthesis of 3-Substituted Indole Derivatives via Three-Component Domino Reaction
2018, 38(4): 855-862
doi: 10.6023/cjoc201709033
Abstract:
The research of indoles has been one of the most active areas of heterocyclic chemistry. In particular, 3-substituted indole derivatives have received much attention as building blocks for the synthesis of many natural products and other biologically active compounds. In this article, an synthetic procedure for multi-substituted indole derivatives was successfully developed by a three-component reaction of phenylglyoxal monohydrate, aromatic amine and 4-hydroxycoumarin with a catalytic amount of trifluoroacetic acid under microwave irradiation conditions. This method has the advantages of simple operation, readily available raw materials, and high atom utilization.
The research of indoles has been one of the most active areas of heterocyclic chemistry. In particular, 3-substituted indole derivatives have received much attention as building blocks for the synthesis of many natural products and other biologically active compounds. In this article, an synthetic procedure for multi-substituted indole derivatives was successfully developed by a three-component reaction of phenylglyoxal monohydrate, aromatic amine and 4-hydroxycoumarin with a catalytic amount of trifluoroacetic acid under microwave irradiation conditions. This method has the advantages of simple operation, readily available raw materials, and high atom utilization.
2018, 38(4): 863-870
doi: 10.6023/cjoc201710025
Abstract:
A novel CuI-catalyzed trifluoromethylation of non-terminal enamides was investigated. N-Arylvinyl-substituted benzamide reacted with Togni reagent in dichloroethylane to afford N-(3, 3, 3-trifluoro-2-arylprop-1-en-1-yl) substituted benzamide. The reaction proceeded at 90℃ in air atmosphere in the presence of base and ligands. Control experiment shows that the Togni reagent firstly released CF3 radical in the presence of copper(I) salts and CF3 radical selectively added to the carbon-carbon double bond of β-position of enamides.
A novel CuI-catalyzed trifluoromethylation of non-terminal enamides was investigated. N-Arylvinyl-substituted benzamide reacted with Togni reagent in dichloroethylane to afford N-(3, 3, 3-trifluoro-2-arylprop-1-en-1-yl) substituted benzamide. The reaction proceeded at 90℃ in air atmosphere in the presence of base and ligands. Control experiment shows that the Togni reagent firstly released CF3 radical in the presence of copper(I) salts and CF3 radical selectively added to the carbon-carbon double bond of β-position of enamides.
2018, 38(4): 871-882
doi: 10.6023/cjoc201711007
Abstract:
Based on the structure of N-(1H-indazol-5-yl)-1-(4-methylbenzyl) pyrrolidine-3-carboxamide (I), which was previously obtained via a structure-based optimization of ROCK 1 inhibitor, sixteen novel 1-substituted-(1H-indazol-5-yl)tetrahydro pyrimidin-2(1H)-one derivatives were designed and synthesized via an active substructure combination strategy. The structures of the target compounds were confirmed by 1H NMR, 13C NMR and HRMS. The bioassay data indicated that 1-(1H-indazol-5-yl)-3-(4-nitrophenyl) tetrahydropyrimidin-2(1H)-one (8a) and 4-(3-(1H-indazol-5-yl)-2-oxo tetrahydropyrimidin-1(2H)-yl)benzonitrile (8b) had good activities against ROCK I. The IC50 values for 8a and 8b were 6.01 and 9.46 μmol·L-1, respectively. Moreover, ex vivo studies demonstrated that 8a and 8b exhibited vasorelaxant activity in rat basilar artery ring. The EC50 values for 8a and 8b were 15.92 and 20.61 μmol·L-1, respectively.
Based on the structure of N-(1H-indazol-5-yl)-1-(4-methylbenzyl) pyrrolidine-3-carboxamide (I), which was previously obtained via a structure-based optimization of ROCK 1 inhibitor, sixteen novel 1-substituted-(1H-indazol-5-yl)tetrahydro pyrimidin-2(1H)-one derivatives were designed and synthesized via an active substructure combination strategy. The structures of the target compounds were confirmed by 1H NMR, 13C NMR and HRMS. The bioassay data indicated that 1-(1H-indazol-5-yl)-3-(4-nitrophenyl) tetrahydropyrimidin-2(1H)-one (8a) and 4-(3-(1H-indazol-5-yl)-2-oxo tetrahydropyrimidin-1(2H)-yl)benzonitrile (8b) had good activities against ROCK I. The IC50 values for 8a and 8b were 6.01 and 9.46 μmol·L-1, respectively. Moreover, ex vivo studies demonstrated that 8a and 8b exhibited vasorelaxant activity in rat basilar artery ring. The EC50 values for 8a and 8b were 15.92 and 20.61 μmol·L-1, respectively.
2018, 38(4): 890-895
doi: 10.6023/cjoc201709052
Abstract:
A general method for synthesis of the variously substituted nitroalkenes via ethylenediaminium trifluoroacetate (EDA-TFA)-catalyzed condensation of nitroalkanes with aryl aldehydes is described. Various aminium salts of ethylenediamine with different acids as well as aminium salts of trifluoroacetic acid with different amines were examined as catalysts, and various solvents were also tested for the reaction. It was found that EDA-TFA is obviously more effective than other aminium salts, and dimethylsulfoxide (DMSO) is better than other solvents. In presence of 5 mol% of EDA-TFA as the catalyst, one-pot reaction of aryl aldehydes with various nitroalkanes in DMSO efficiently afforded variously substituted nitroalkenes in 82%~96% yields.
A general method for synthesis of the variously substituted nitroalkenes via ethylenediaminium trifluoroacetate (EDA-TFA)-catalyzed condensation of nitroalkanes with aryl aldehydes is described. Various aminium salts of ethylenediamine with different acids as well as aminium salts of trifluoroacetic acid with different amines were examined as catalysts, and various solvents were also tested for the reaction. It was found that EDA-TFA is obviously more effective than other aminium salts, and dimethylsulfoxide (DMSO) is better than other solvents. In presence of 5 mol% of EDA-TFA as the catalyst, one-pot reaction of aryl aldehydes with various nitroalkanes in DMSO efficiently afforded variously substituted nitroalkenes in 82%~96% yields.
2018, 38(4): 896-901
doi: 10.6023/cjoc201710031
Abstract:
Organo-phosphorus compounds have important applications in metal-organic chemistry, coordination chemistry and biochemistry. Therefore, the C-P cross-coupling reaction was an important method to prepare organo-phosphorus, which is also a hotspot of current research. Hence, we have studied a kind of cross-coupling reaction between arenesulphonate and phosphites using palladium as the catalyst to synthesize a series of organo-phosphorus compounds efficiently, and the approach was applied to prepare a chiral N/P ligand.
Organo-phosphorus compounds have important applications in metal-organic chemistry, coordination chemistry and biochemistry. Therefore, the C-P cross-coupling reaction was an important method to prepare organo-phosphorus, which is also a hotspot of current research. Hence, we have studied a kind of cross-coupling reaction between arenesulphonate and phosphites using palladium as the catalyst to synthesize a series of organo-phosphorus compounds efficiently, and the approach was applied to prepare a chiral N/P ligand.
2018, 38(4): 912-918
doi: 10.6023/cjoc201708057
Abstract:
MCM-41@Schiff base-Mn(OAc)2, a heterogeneous catalyst, was used for one pot synthesis of xanthene derivatives in water with aldehydes, 5, 5-dimethyl-1, 3-cyclohexanedione and 2-naphthol. This method exhibited some advantages including excellent yields, environmentally benign and good functional group tolerance, and the catalytic system presented some features of the less amount of catalyst and excellent reusability by experiment.
MCM-41@Schiff base-Mn(OAc)2, a heterogeneous catalyst, was used for one pot synthesis of xanthene derivatives in water with aldehydes, 5, 5-dimethyl-1, 3-cyclohexanedione and 2-naphthol. This method exhibited some advantages including excellent yields, environmentally benign and good functional group tolerance, and the catalytic system presented some features of the less amount of catalyst and excellent reusability by experiment.
2018, 38(4): 919-925
doi: 10.6023/cjoc201711016
Abstract:
Nine novel diosgenin derivatives were designed and synthesized by using diosgenin as a precursor. Their structures were identified by 1H NMR, 13C NMR, IR and HRMS. Antitumor activity (A549, A431, H1975, HCT-116, Aspc-1, Ramos) and cytotoxicity (HBE, LO-2) were measured for all derivatives using thiazolyl blue tetrazolium bromide (MTT). The results show that most diosgenin derivatives have significant anti-tumor activity and low cytotoxicity.
Nine novel diosgenin derivatives were designed and synthesized by using diosgenin as a precursor. Their structures were identified by 1H NMR, 13C NMR, IR and HRMS. Antitumor activity (A549, A431, H1975, HCT-116, Aspc-1, Ramos) and cytotoxicity (HBE, LO-2) were measured for all derivatives using thiazolyl blue tetrazolium bromide (MTT). The results show that most diosgenin derivatives have significant anti-tumor activity and low cytotoxicity.
2018, 38(4): 931-939
doi: 10.6023/cjoc201709001
Abstract:
Ethyl 5-phenyl-2-(3-(trifluoromethyl)phenyl)-2H-1, 2, 3-triazole-4-carboxylate (EPFC), a newly synthesized compound, is used to study its structural properties and explore as a fluorescent probe for metal ions. EPFC was investigated in terms of structural, fluorescence spectroscopic, UV-Vis spectroscopic and theoretical analysis by using HF/6-31G(d), CIS/6-31G(d) and B3LYP/6-31G(d) methods, respectively. The corresponding product was characterized by NMR and HRESIMS methods. The interactions of the compound with 15 kinds of metal ions (Pb2+, Mn2+, K+, Na+, Ag+, Ca2+, Cd2+, Co2+, Cu2+, Fe3+, Zn2+, Ni2+, Hg2+, Li+ and Mg2+) were investigated by UV absorption spectroscopy and fluorescence spectroscopy. The quantum chemical values suggested that it is easy for EPFC to lose electron with weak electron accepting ability by frontier molecular orbital analysis. The calculated spectra were complimented with experimental measurements in great degree. In addition, a novel rhodamine B derivative containing 1, 2, 3-triazole unit, and REPFC was successfully designed and synthesized by the reaction between rhodamine B and EPFC. REPFC displayed more selectivity response to Hg2+ ion than other metal ions in N, N-dimethylformamide (DMF)-H2O (V/V=1/1, pH 7.4) within a REPFC concentration range of 2.67×10-5~4.67×10-5 mol·L-1 with an fluorescent enhancement and a rapid chemical reaction. The triazole appended colorless chemosensor turns to pink upon complex formation only with Hg2+ions even in the presence of other common metal ions and enables naked-eye detection. The coordination mechanism and turn on/off fluorescence for Hg2+ ions were well proposed by explaining Hg2+ inducing the ring-opened rhodamine B moiety. This study was an advancement for the application of 1, 2, 3-triazole compound and provides guidance for using simple and high-selectivity Hg2+ probes in aqueous solutions under physiological conditions.
Ethyl 5-phenyl-2-(3-(trifluoromethyl)phenyl)-2H-1, 2, 3-triazole-4-carboxylate (EPFC), a newly synthesized compound, is used to study its structural properties and explore as a fluorescent probe for metal ions. EPFC was investigated in terms of structural, fluorescence spectroscopic, UV-Vis spectroscopic and theoretical analysis by using HF/6-31G(d), CIS/6-31G(d) and B3LYP/6-31G(d) methods, respectively. The corresponding product was characterized by NMR and HRESIMS methods. The interactions of the compound with 15 kinds of metal ions (Pb2+, Mn2+, K+, Na+, Ag+, Ca2+, Cd2+, Co2+, Cu2+, Fe3+, Zn2+, Ni2+, Hg2+, Li+ and Mg2+) were investigated by UV absorption spectroscopy and fluorescence spectroscopy. The quantum chemical values suggested that it is easy for EPFC to lose electron with weak electron accepting ability by frontier molecular orbital analysis. The calculated spectra were complimented with experimental measurements in great degree. In addition, a novel rhodamine B derivative containing 1, 2, 3-triazole unit, and REPFC was successfully designed and synthesized by the reaction between rhodamine B and EPFC. REPFC displayed more selectivity response to Hg2+ ion than other metal ions in N, N-dimethylformamide (DMF)-H2O (V/V=1/1, pH 7.4) within a REPFC concentration range of 2.67×10-5~4.67×10-5 mol·L-1 with an fluorescent enhancement and a rapid chemical reaction. The triazole appended colorless chemosensor turns to pink upon complex formation only with Hg2+ions even in the presence of other common metal ions and enables naked-eye detection. The coordination mechanism and turn on/off fluorescence for Hg2+ ions were well proposed by explaining Hg2+ inducing the ring-opened rhodamine B moiety. This study was an advancement for the application of 1, 2, 3-triazole compound and provides guidance for using simple and high-selectivity Hg2+ probes in aqueous solutions under physiological conditions.
2018, 38(4): 840-845
doi: 10.6023/cjoc201710023
Abstract:
Mevalocidin is a phytotoxin, produced by two fungal isolates designated Rosellinia DA092917 and Fusarium DA056446, and has a broad spectrum of post emergence herbicidal activity at relatively high rate (4 kg/ha). Structural modification of mevalocidin at its chiral center was investigated with the aim of discovering of novel herbicides with improved activity. In order to determine the role of hydroxyl and methyl groups of mevalocidin exhibiting the herbicidal activity, we designed (±)-deoxy-mevalocidin (1) and (±)-demethyl-mevalocidin (2), respectively. These two designed compounds were synthesized (racemate) through two different synthetic approaches and characterized by 1H NMR, 13C NMR and HRMS spectra. The herbicidal activities of the synthesized compounds were evaluated against both dicotyledon and monocotyledon weeds. Bioassay results indicated that the both synthesized analogues lost the herbicidal activity when compared to parent and it demonstrated that methyl and/or hydroxyl groups at the chiral center of mevalocidin are crucial for its herbicidal activity. Thus, this study will provide insights into the structural modification of mevalocidin.
Mevalocidin is a phytotoxin, produced by two fungal isolates designated Rosellinia DA092917 and Fusarium DA056446, and has a broad spectrum of post emergence herbicidal activity at relatively high rate (4 kg/ha). Structural modification of mevalocidin at its chiral center was investigated with the aim of discovering of novel herbicides with improved activity. In order to determine the role of hydroxyl and methyl groups of mevalocidin exhibiting the herbicidal activity, we designed (±)-deoxy-mevalocidin (1) and (±)-demethyl-mevalocidin (2), respectively. These two designed compounds were synthesized (racemate) through two different synthetic approaches and characterized by 1H NMR, 13C NMR and HRMS spectra. The herbicidal activities of the synthesized compounds were evaluated against both dicotyledon and monocotyledon weeds. Bioassay results indicated that the both synthesized analogues lost the herbicidal activity when compared to parent and it demonstrated that methyl and/or hydroxyl groups at the chiral center of mevalocidin are crucial for its herbicidal activity. Thus, this study will provide insights into the structural modification of mevalocidin.
2018, 38(4): 846-854
doi: 10.6023/cjoc201711014
Abstract:
Deep eutectic solvent based on L-proline and oxalic acid has been demonstrated for the first time as an efficient catalyst for synthesis of 4, 7-dihydro-1H-pyrazolo[3, 4-b] pyridine-5-carbonitrile derivatives via one-pot three-component reaction of aldehyde, 3-oxopropanenitrile and 1H-pyrazol-5-amine. The key features of this approach include the broad substrate scope, operational simplicity, recyclable catalyst and possibility to scale up giving multigram quantities.
Deep eutectic solvent based on L-proline and oxalic acid has been demonstrated for the first time as an efficient catalyst for synthesis of 4, 7-dihydro-1H-pyrazolo[3, 4-b] pyridine-5-carbonitrile derivatives via one-pot three-component reaction of aldehyde, 3-oxopropanenitrile and 1H-pyrazol-5-amine. The key features of this approach include the broad substrate scope, operational simplicity, recyclable catalyst and possibility to scale up giving multigram quantities.
2018, 38(4): 883-889
doi: 10.6023/cjoc201709021
Abstract:
Thirteen matrine derivatives were synthesized with high yield with one step in aqueous phase. The chemical structures of the synthesized compounds were characterized by 1H NMR, 13C NMR and HRMS. Three crystals of compound 13-(piperidin-1-yl)matrine (a), 13-(piperidin-1-yl)carbodithioate matrine (k) and 13-(morpholin-4-yl) carbodithioate matrine (m) were obtained and X-ray diffraction data showed that their structures included five chiral carbon atoms with the absolute configuration of 5(S), 6(S), 7(R), 11(R) and 13(S). Meanwhile, there were three classical hydrogen bonds:O(2)-H(21B)…N(2), O(2)-H(21A)…O(1) and C(9)-H(9A)…O(1) by analyzing the data of compound 13-(piperidin-1-yl) matrine (a). These strong hydrogen bonds can play a key role in the accumulation of crystals. Biological studies indicated that the synthetic derivatives had some inhibitory effect against SW480, A549 and A431 cells. The introduction of N or S atom at C-13 position of matrine could improve the antitumor activity.
Thirteen matrine derivatives were synthesized with high yield with one step in aqueous phase. The chemical structures of the synthesized compounds were characterized by 1H NMR, 13C NMR and HRMS. Three crystals of compound 13-(piperidin-1-yl)matrine (a), 13-(piperidin-1-yl)carbodithioate matrine (k) and 13-(morpholin-4-yl) carbodithioate matrine (m) were obtained and X-ray diffraction data showed that their structures included five chiral carbon atoms with the absolute configuration of 5(S), 6(S), 7(R), 11(R) and 13(S). Meanwhile, there were three classical hydrogen bonds:O(2)-H(21B)…N(2), O(2)-H(21A)…O(1) and C(9)-H(9A)…O(1) by analyzing the data of compound 13-(piperidin-1-yl) matrine (a). These strong hydrogen bonds can play a key role in the accumulation of crystals. Biological studies indicated that the synthetic derivatives had some inhibitory effect against SW480, A549 and A431 cells. The introduction of N or S atom at C-13 position of matrine could improve the antitumor activity.
2018, 38(4): 902-911
doi: 10.6023/cjoc201710034
Abstract:
A metal-free esterification of various aldehydes or carboxylic acids with quaternary ammonium salts has been developed for selective synthesis of esters. A possible mechanism containing radical process that aldehyde converts to carboxylic acid and the generation of iodohydrocarbon via C-N bond cleavage of quaternary ammonium salt is proposed.
A metal-free esterification of various aldehydes or carboxylic acids with quaternary ammonium salts has been developed for selective synthesis of esters. A possible mechanism containing radical process that aldehyde converts to carboxylic acid and the generation of iodohydrocarbon via C-N bond cleavage of quaternary ammonium salt is proposed.
2018, 38(4): 926-930
doi: 10.6023/cjoc201708061
Abstract:
A novel rhodamine B Schiff-base fluorescence probe 1 was synthesized and characterized by 1H NMR, 13C NMR, MS and single-crystal X-ray analysis. The recognition properties of the probe 1 with Hg2+ ions were investigated in ethanol-water (V/V=7/3, HEPES 10 mmol/L, pH=7.0) by the UV-Vis spectrophotometry and the fluorescence spectrophotometry. The probe 1 showed remarkable "turn-on" fluorescent responses to Hg2+ with good selectivity over the other metal ions examined. The 1:1 binding model of probe 1 with Hg2+ was established by Job's plot and MS spectra. The probe can be applied to the quantitative analysis of Hg2+ with a linear range covering from 0 to 50 μmol/L. The fluorescence imaging experiments in MGC-803 living cells demonstrated that 1 could be used in biological systems to monitor Hg2+.
A novel rhodamine B Schiff-base fluorescence probe 1 was synthesized and characterized by 1H NMR, 13C NMR, MS and single-crystal X-ray analysis. The recognition properties of the probe 1 with Hg2+ ions were investigated in ethanol-water (V/V=7/3, HEPES 10 mmol/L, pH=7.0) by the UV-Vis spectrophotometry and the fluorescence spectrophotometry. The probe 1 showed remarkable "turn-on" fluorescent responses to Hg2+ with good selectivity over the other metal ions examined. The 1:1 binding model of probe 1 with Hg2+ was established by Job's plot and MS spectra. The probe can be applied to the quantitative analysis of Hg2+ with a linear range covering from 0 to 50 μmol/L. The fluorescence imaging experiments in MGC-803 living cells demonstrated that 1 could be used in biological systems to monitor Hg2+.
2018, 38(4): 940-948
doi: 10.6023/cjoc201709007
Abstract:
5-Hydroxymethylfurfural (5-HMF) is one of the most important biomass-derived platform compounds and can be used to produce various chemicals. The synthesis of 5-hydroxymethylfurfural (5-HMF) from sucrose catalyzed by a variety of phosphotungstate (Nb0.6PW12O40, Sn0.75PW12O40, CrPW12O40, CePW12O40) has been studied, and the catalysts are characterized by FTIR, XRD, UV-Vis, TGA, NH3-TPD and NMR. The optimum yield of 5-HMF reached 62.54% with 99.3% conversion of sucrose, using Nb0.6PW12O40 in dimethyl sulfoxide (DMSO) at 80℃ under 0.1 MPa of N2 with reaction time of 90 min. Moreover, Nb0.6PW12O40 could be reused five times without loss of activity, and the reaction mechanism was proposed. This study has reference significance for carbohydrate conversion to 5-HMF .
5-Hydroxymethylfurfural (5-HMF) is one of the most important biomass-derived platform compounds and can be used to produce various chemicals. The synthesis of 5-hydroxymethylfurfural (5-HMF) from sucrose catalyzed by a variety of phosphotungstate (Nb0.6PW12O40, Sn0.75PW12O40, CrPW12O40, CePW12O40) has been studied, and the catalysts are characterized by FTIR, XRD, UV-Vis, TGA, NH3-TPD and NMR. The optimum yield of 5-HMF reached 62.54% with 99.3% conversion of sucrose, using Nb0.6PW12O40 in dimethyl sulfoxide (DMSO) at 80℃ under 0.1 MPa of N2 with reaction time of 90 min. Moreover, Nb0.6PW12O40 could be reused five times without loss of activity, and the reaction mechanism was proposed. This study has reference significance for carbohydrate conversion to 5-HMF .
2018, 38(4): 949-954
doi: 10.6023/cjoc201711005
Abstract:
Dihydroisoxazoline is a heterocyclic compound with a variety of biological properties. In this study, ten new 3-(4-piperazinyl)phenyl-5-(2-furyl)-4, 5-dihydroisoxazoline derivatives (3~12) have been prepared by the general principle of molecular hybridization based on former work. The structures were characterized by IR, 1H NMR, 13C NMR and HRMS. In vitro cytotoxic activity against a panel of human tumor cell lines (Hela, A549 and SGC7901) was evaluated by the 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) assay. The result indicated that dihydroisoxazoline derivatives showed potential cytotoxic activity, and the substituents of the NH group of piperazine ring had an obvious influence on cytotoxic activities. Especially, compound 4, 6 and 11 were found to be better inhibition against human tumor cell lines, which were found to be similar cytotoxic activity to positive control 5-fluorouracil. Further FACs analysis showed that compounds 4 and 11 significantly induced death in A549 cell.
Dihydroisoxazoline is a heterocyclic compound with a variety of biological properties. In this study, ten new 3-(4-piperazinyl)phenyl-5-(2-furyl)-4, 5-dihydroisoxazoline derivatives (3~12) have been prepared by the general principle of molecular hybridization based on former work. The structures were characterized by IR, 1H NMR, 13C NMR and HRMS. In vitro cytotoxic activity against a panel of human tumor cell lines (Hela, A549 and SGC7901) was evaluated by the 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) assay. The result indicated that dihydroisoxazoline derivatives showed potential cytotoxic activity, and the substituents of the NH group of piperazine ring had an obvious influence on cytotoxic activities. Especially, compound 4, 6 and 11 were found to be better inhibition against human tumor cell lines, which were found to be similar cytotoxic activity to positive control 5-fluorouracil. Further FACs analysis showed that compounds 4 and 11 significantly induced death in A549 cell.
2018, 38(4): 955-962
doi: 10.6023/cjoc201708056
Abstract:
In this work, two novel pyridinium N-chloramine precursors were designed and synthesized, both of which contain perfluorophenyl azide (PFPA) unit as the photo-coupling handle. The synthetic precursors were photo immobilized on commercial PU films upon UV (254 nm) light irradiation. After exposure to diluted household bleach, the resulting PU films were rendered biocidal. Antibacterial tests showed that satisfactory was achieved for both surface modified films and that the film grafted with shorter alkyl linker-contained precursor demonstrated even higher biocidal efficacy. Non-leaching antibacterial PU materials were herein developed based on PFPA-coupling strategy, providing a simple and universal method to confer N-chloramines on inert polymer surface for antibacterial application.
In this work, two novel pyridinium N-chloramine precursors were designed and synthesized, both of which contain perfluorophenyl azide (PFPA) unit as the photo-coupling handle. The synthetic precursors were photo immobilized on commercial PU films upon UV (254 nm) light irradiation. After exposure to diluted household bleach, the resulting PU films were rendered biocidal. Antibacterial tests showed that satisfactory was achieved for both surface modified films and that the film grafted with shorter alkyl linker-contained precursor demonstrated even higher biocidal efficacy. Non-leaching antibacterial PU materials were herein developed based on PFPA-coupling strategy, providing a simple and universal method to confer N-chloramines on inert polymer surface for antibacterial application.
2018, 38(4): 969-974
doi: 10.6023/cjoc201710010
Abstract:
The in situ generated aryl-alkyl unsymmetrical thioureas were prepared by the reaction of aryl isothiocyanate with cyclic aliphatic secondary amine. Then, the thioamidoguanidino derivatives instead of the expected Hugerschoff product 2-aminobenzothiazole were obtained from unsymmetrical thioureas using iodosobenzene diacetate and Et3N under solvent-free grinding conditions. The advantages of this procedure are simple operation, mild reaction conditions, and solvent-free. The products were identified by IR, HRMS, 1H NMR and 13C NMR. The reported method is an efficient approach for the synthesis of thioamidoguanidine derivatives.
The in situ generated aryl-alkyl unsymmetrical thioureas were prepared by the reaction of aryl isothiocyanate with cyclic aliphatic secondary amine. Then, the thioamidoguanidino derivatives instead of the expected Hugerschoff product 2-aminobenzothiazole were obtained from unsymmetrical thioureas using iodosobenzene diacetate and Et3N under solvent-free grinding conditions. The advantages of this procedure are simple operation, mild reaction conditions, and solvent-free. The products were identified by IR, HRMS, 1H NMR and 13C NMR. The reported method is an efficient approach for the synthesis of thioamidoguanidine derivatives.
2018, 38(4): 963-968
doi: 10.6023/cjoc201710027
Abstract:
A mild and highly efficient reductive coupling of α-bromoketones with sulfonyl chlorides is described. Various β-ketosulfones can be obtained under mild conditions in good to excellent yields. This method provides a simple and practical access to β-ketosulfones and is amenable to gram scale with no special precautions to exclude air or moisture.
A mild and highly efficient reductive coupling of α-bromoketones with sulfonyl chlorides is described. Various β-ketosulfones can be obtained under mild conditions in good to excellent yields. This method provides a simple and practical access to β-ketosulfones and is amenable to gram scale with no special precautions to exclude air or moisture.
2018, 38(4): 975-980
doi: 10.6023/cjoc201710030
Abstract:
Base-mediated cyclization of 1-diazo-2, 4-dioxo-5-ynylphosphonate provided novel 3-phosphonyl pyrano[3, 2-c] pyrazol-7(1H)-one derivatives in 48%~99% yields. Mild conditions, simple manipulation and functional group diversity are the salient features of this methodology.
Base-mediated cyclization of 1-diazo-2, 4-dioxo-5-ynylphosphonate provided novel 3-phosphonyl pyrano[3, 2-c] pyrazol-7(1H)-one derivatives in 48%~99% yields. Mild conditions, simple manipulation and functional group diversity are the salient features of this methodology.
