A new mononuclear Cu（II） complex, [Cu（L）] （H2L = 4,4′,6,6v-tetrabromo-2,2′- [ethylenedioxybis（nitrilomethylidyne）]diphenol）, has been synthesized and structurally characterized. X-ray crystal structure of th...A new mononuclear Cu（II） complex, [Cu（L）] （H2L = 4,4′,6,6v-tetrabromo-2,2′- [ethylenedioxybis（nitrilomethylidyne）]diphenol）, has been synthesized and structurally characterized. X-ray crystal structure of the complex reveals that the Cu（Ⅱ） ion is four-coordinated by two oxygen atoms and two nitrogen atoms from L2- unit. Crystallographic data： monoclinic, space group P21/n with a = 14.076（2）, b = 6.9801（14）, c = 19.858 （2） A, β= 107.613（2）°, C16n10Br4CuN2O4, Mr = 677.44, V = 1859.6（5） A3, Dc = 2.420 g/cm3,μ = 9.796 mm^-1, F（000） = 1284, Z = 4, the final R = 0.0516 and wR = 0.0938 for 1879 observed reflections with I 〉 2σ（/）. The dihedral angel between the two coordination planes of Cu（1）-N（2）--O（4） and Cu（1 ）-N（ 1 ）-O（3）） is 30.08（6）°.展开更多
A series of structurally related diphenol aldimines (DPAs) were synthesized. These aldimines involve different substitution patterns of their phenolic groups, for the purpose of optimizing their ability to inhibit ATP...A series of structurally related diphenol aldimines (DPAs) were synthesized. These aldimines involve different substitution patterns of their phenolic groups, for the purpose of optimizing their ability to inhibit ATP synthase. The inhibitory effects of these DPA compounds were evaluated using purified F1 and membrane-bound F1F0 E. coli ATP synthase. Structure-activity relationship studies of these di-phenol compounds showed that maximum inhibition was achieved when both phenolic groups are either in the meta-positions (DPA-7, IC50 = 2.0 μM), or in the ortho-positions (DPA-9, IC50 = 5.0 μM). The lowest ATP synthase inhibition was found to be when the phenolic groups are both in the para-positions (DPA-2, IC50 = 100.0 μM). Results also show that the inhibitory effects of these compounds on ATPase are completely reversible. Identical inhibition patterns of both the purified F1 and the membrane bound F1F0 enzyme were observed. Study of E. coli cell growth showed that these diphenol aldimines effectively inhibit both ATP synthesis and cell growth.展开更多
A novel catalyst, MgFe 2O 4, for hydroxylation of phenol with hydrogen peroxide was synthesized via coprecipitation method from an aqueous solution containing Fe(NO 3) 3·9H 2O and Mg(NO 3) 2·6H 2O with ammon...A novel catalyst, MgFe 2O 4, for hydroxylation of phenol with hydrogen peroxide was synthesized via coprecipitation method from an aqueous solution containing Fe(NO 3) 3·9H 2O and Mg(NO 3) 2·6H 2O with ammonia. The X ray diffraction peaks of the catalyst show that the as prepared sample has engendered MgFe 2O 4 crystal with spinel structure, which is also confirmed by its IR spectrum. In the hydroxylation of phenol with hydrogen peroxide, MgFe 2O 4 catalyst exhibited high activity after a short induction period. In particular, the addition of a little amount of acetic acid in the reaction liquid can effectively shorten the induction period. Under the same reaction conditions, the diphenol selectivity over MgFe 2O 4 is higher than that over TS 1, furthermore, the reaction time is shortened greatly. The experimental phenomena can be explained by the free radical mechanism.展开更多
基金This work was supported by the Foundation of Education Department of Gansu Province (No. 0604-01)the 'Qing Lan' Talent Engineering Funds of Lanzhou Jiaotong University (No. QL-03-01A)
文摘A new mononuclear Cu（II） complex, [Cu（L）] （H2L = 4,4′,6,6v-tetrabromo-2,2′- [ethylenedioxybis（nitrilomethylidyne）]diphenol）, has been synthesized and structurally characterized. X-ray crystal structure of the complex reveals that the Cu（Ⅱ） ion is four-coordinated by two oxygen atoms and two nitrogen atoms from L2- unit. Crystallographic data： monoclinic, space group P21/n with a = 14.076（2）, b = 6.9801（14）, c = 19.858 （2） A, β= 107.613（2）°, C16n10Br4CuN2O4, Mr = 677.44, V = 1859.6（5） A3, Dc = 2.420 g/cm3,μ = 9.796 mm^-1, F（000） = 1284, Z = 4, the final R = 0.0516 and wR = 0.0938 for 1879 observed reflections with I 〉 2σ（/）. The dihedral angel between the two coordination planes of Cu（1）-N（2）--O（4） and Cu（1 ）-N（ 1 ）-O（3）） is 30.08（6）°.
文摘A series of structurally related diphenol aldimines (DPAs) were synthesized. These aldimines involve different substitution patterns of their phenolic groups, for the purpose of optimizing their ability to inhibit ATP synthase. The inhibitory effects of these DPA compounds were evaluated using purified F1 and membrane-bound F1F0 E. coli ATP synthase. Structure-activity relationship studies of these di-phenol compounds showed that maximum inhibition was achieved when both phenolic groups are either in the meta-positions (DPA-7, IC50 = 2.0 μM), or in the ortho-positions (DPA-9, IC50 = 5.0 μM). The lowest ATP synthase inhibition was found to be when the phenolic groups are both in the para-positions (DPA-2, IC50 = 100.0 μM). Results also show that the inhibitory effects of these compounds on ATPase are completely reversible. Identical inhibition patterns of both the purified F1 and the membrane bound F1F0 enzyme were observed. Study of E. coli cell growth showed that these diphenol aldimines effectively inhibit both ATP synthesis and cell growth.
文摘A novel catalyst, MgFe 2O 4, for hydroxylation of phenol with hydrogen peroxide was synthesized via coprecipitation method from an aqueous solution containing Fe(NO 3) 3·9H 2O and Mg(NO 3) 2·6H 2O with ammonia. The X ray diffraction peaks of the catalyst show that the as prepared sample has engendered MgFe 2O 4 crystal with spinel structure, which is also confirmed by its IR spectrum. In the hydroxylation of phenol with hydrogen peroxide, MgFe 2O 4 catalyst exhibited high activity after a short induction period. In particular, the addition of a little amount of acetic acid in the reaction liquid can effectively shorten the induction period. Under the same reaction conditions, the diphenol selectivity over MgFe 2O 4 is higher than that over TS 1, furthermore, the reaction time is shortened greatly. The experimental phenomena can be explained by the free radical mechanism.
