Some more new sulfur compounds bearing heterocyclic systems mainly 2-thioxo-1,3,4-thiadiazinone derivatives 2-7 and 3-thioxo-1,2,4-triazole derivatives 9 have been synthetic via alkylation, acylation and condensation ...Some more new sulfur compounds bearing heterocyclic systems mainly 2-thioxo-1,3,4-thiadiazinone derivatives 2-7 and 3-thioxo-1,2,4-triazole derivatives 9 have been synthetic via alkylation, acylation and condensation of dithioic formic acid hydrazide 1 through ring closure reactions with α,β-bi functional groups compounds. Most of the obtained target showed a highly activity towards some microbial in compare with two references antibiotics, Pipercillin and Mycostatine. The structures of the products have been established from their elemental and spectral analysis.展开更多
Three mono-cyclopentadienyl metal complexes, [C_6H_4O_2]CpTiCl (Ⅰ),[C_(12)H_8O_2]CpTiCl (Ⅱ), and [C_(20)H_(12)O_2] CpTiCl (Ⅲ), were prepared via the reactions ofcyclopentadienyl titanium trichloride with catechol, ...Three mono-cyclopentadienyl metal complexes, [C_6H_4O_2]CpTiCl (Ⅰ),[C_(12)H_8O_2]CpTiCl (Ⅱ), and [C_(20)H_(12)O_2] CpTiCl (Ⅲ), were prepared via the reactions ofcyclopentadienyl titanium trichloride with catechol, 2,2i-bisphenol, and 2,2'-bisnaphthol,respectively. In the presence of a moderate amount of methylaluminoxane (MAO), the complexesexhibited catalytic activities for ethylene polymerization. Complex Ⅰ showed the highest activityat Al/Ti molar ratio of 500 at the temperature of 30℃. With increasing of polymerizationtemperature, catalytic activities and molecular weight of the obtained polyethylene tended todecrease, and molecular weight distribution of polyethylene became narrower. With the molecularsimulation method, the charges on titanium atoms of complexes Ⅰ, Ⅱ, and Ⅲ, and the bond anglesformed by Ti and bisphenoxy ligands were calculated. It was concluded that the smaller the netcharge on Ti and the smaller the angle of O1―Ti―O2, the higher the activity of the complex.展开更多
Structural analogues of bicyclic peroxides belonging to the G factors family have been synthesised under Mannieh type conditions, followed by an autoxidation step furnishing exclusively the peroxide. As electron trans...Structural analogues of bicyclic peroxides belonging to the G factors family have been synthesised under Mannieh type conditions, followed by an autoxidation step furnishing exclusively the peroxide. As electron transfer from heine or free iron to peroxide is the first step in the mode of action ofartemisinin -like compound, Fe（fl） induced reduction was studied and the reactivity of the intermediate C-centered radical formed was correlated to the antimalarial activity. Dissociative electron transfer was studied by electrochemistry and allowed the evaluation of the standard reduction potentials and other pertinent thermochemical information. These bicyclic peroxides were evaluated in vitro against Plasmodium falciparum and revealed moderate to good activity.展开更多
A variety of unique Al(salen) complexes functionalized by imidazolium-based ionic liquid(IL) moieties with the salen ligand at the two sides of 3,3′-position have been successfully prepared, rather than familiar 5,5...A variety of unique Al(salen) complexes functionalized by imidazolium-based ionic liquid(IL) moieties with the salen ligand at the two sides of 3,3′-position have been successfully prepared, rather than familiar 5,5′-position reported previously.The catalytic activity obtained by these bifunctional catalysts could be superior to those of the binary type catalysts in the formation of five-membered heterocyclic compounds from the cycloaddition reaction of CO_2 and three-membered heterocyclic compounds(including terminal epoxides and N-substituted aziridines), presumably due to the distinguished intramolecularly synergistic catalysis, which might lead to perform the cycloaddition reaction at ambient conditions and retain excellent yield and unprecedented chemo-or regioselectivity. Moreover, the polyether-based trifunctional Al(salen) catalysts with the best catalytic performance could be regenerated and reused at least eight times without any obvious decreases in catalytic activity. Finally,the kinetic investigation suggested the structure of catalysts had important influences on the catalytic activity, thereby proposing the possible reaction mechanism.展开更多
文摘Some more new sulfur compounds bearing heterocyclic systems mainly 2-thioxo-1,3,4-thiadiazinone derivatives 2-7 and 3-thioxo-1,2,4-triazole derivatives 9 have been synthetic via alkylation, acylation and condensation of dithioic formic acid hydrazide 1 through ring closure reactions with α,β-bi functional groups compounds. Most of the obtained target showed a highly activity towards some microbial in compare with two references antibiotics, Pipercillin and Mycostatine. The structures of the products have been established from their elemental and spectral analysis.
基金The work is supported by Special Funds for State Major Basic Research Projects of China(No.G1999064801)
文摘Three mono-cyclopentadienyl metal complexes, [C_6H_4O_2]CpTiCl (Ⅰ),[C_(12)H_8O_2]CpTiCl (Ⅱ), and [C_(20)H_(12)O_2] CpTiCl (Ⅲ), were prepared via the reactions ofcyclopentadienyl titanium trichloride with catechol, 2,2i-bisphenol, and 2,2'-bisnaphthol,respectively. In the presence of a moderate amount of methylaluminoxane (MAO), the complexesexhibited catalytic activities for ethylene polymerization. Complex Ⅰ showed the highest activityat Al/Ti molar ratio of 500 at the temperature of 30℃. With increasing of polymerizationtemperature, catalytic activities and molecular weight of the obtained polyethylene tended todecrease, and molecular weight distribution of polyethylene became narrower. With the molecularsimulation method, the charges on titanium atoms of complexes Ⅰ, Ⅱ, and Ⅲ, and the bond anglesformed by Ti and bisphenoxy ligands were calculated. It was concluded that the smaller the netcharge on Ti and the smaller the angle of O1―Ti―O2, the higher the activity of the complex.
文摘Structural analogues of bicyclic peroxides belonging to the G factors family have been synthesised under Mannieh type conditions, followed by an autoxidation step furnishing exclusively the peroxide. As electron transfer from heine or free iron to peroxide is the first step in the mode of action ofartemisinin -like compound, Fe（fl） induced reduction was studied and the reactivity of the intermediate C-centered radical formed was correlated to the antimalarial activity. Dissociative electron transfer was studied by electrochemistry and allowed the evaluation of the standard reduction potentials and other pertinent thermochemical information. These bicyclic peroxides were evaluated in vitro against Plasmodium falciparum and revealed moderate to good activity.
基金supported by the National Science for Distinguished Young Scholars of China(21425627)the National Natural Science Foundation of China(21676306)+1 种基金the Natural Science Foundation of Guangdong Province(2016A030310211,2015A030313104)the Fundamental Research Funds for the Central Universities of Sun Yat-sen University
文摘A variety of unique Al(salen) complexes functionalized by imidazolium-based ionic liquid(IL) moieties with the salen ligand at the two sides of 3,3′-position have been successfully prepared, rather than familiar 5,5′-position reported previously.The catalytic activity obtained by these bifunctional catalysts could be superior to those of the binary type catalysts in the formation of five-membered heterocyclic compounds from the cycloaddition reaction of CO_2 and three-membered heterocyclic compounds(including terminal epoxides and N-substituted aziridines), presumably due to the distinguished intramolecularly synergistic catalysis, which might lead to perform the cycloaddition reaction at ambient conditions and retain excellent yield and unprecedented chemo-or regioselectivity. Moreover, the polyether-based trifunctional Al(salen) catalysts with the best catalytic performance could be regenerated and reused at least eight times without any obvious decreases in catalytic activity. Finally,the kinetic investigation suggested the structure of catalysts had important influences on the catalytic activity, thereby proposing the possible reaction mechanism.
