3,3'-Bis(5-(N-(4-hydroxylphenyl)imidomethyl)pyrrol-2-yl)pentane 1 has been synthesized and characterized. The crystal of its methanol complex, 1·(CH3OH)2, belongs to the orthorhombic system, space group ...3,3'-Bis(5-(N-(4-hydroxylphenyl)imidomethyl)pyrrol-2-yl)pentane 1 has been synthesized and characterized. The crystal of its methanol complex, 1·(CH3OH)2, belongs to the orthorhombic system, space group Pccn with a = 18.094(2), b = 11.6890(16), c = 13.3629(19) , V = 2826.3(7) 3, Z = 8, C14.5H18N2O2, Mr = 252.31, Dc = 1.186 g/cm3, F(000) = 1080 and μ(MoKα) = 0.080 mm-1. The final R = 0.0662 and wR = 0.1801 for 1908 observed reflections with I 2σ(I), and R = 0.0800 and wR = 0.1948 for all reflections. In the solid state, bridged by included methanol molecules, the molecules of compound 1 form interpenetrated grid structure through N–H···O and O–H···O hydrogen bonds.展开更多
The dioxygen activation catalyzed by 4-hydorxylphenyl pyruvate dioxygenase(HPPD)were reinvestigated by using hybrid quantum mechanics/molecular mechanics(QM/MM)approaches at the B3LYP/6-311++G(d,p):AMBER level.These s...The dioxygen activation catalyzed by 4-hydorxylphenyl pyruvate dioxygenase(HPPD)were reinvestigated by using hybrid quantum mechanics/molecular mechanics(QM/MM)approaches at the B3LYP/6-311++G(d,p):AMBER level.These studies showed that this reaction consisted of two steps including the dioxygen addition/decarboxylation and hetero O-O bond cleavage,where the first step was found to be rate-determining.The former step initially runs on a septet potential energy surface(PES),then switches to a quintet PES after crossing a septet/quintet minimum energy crossing point(MECP)5-7M2,whereas the rest step runs on the quintet PES.The reliability of our theoretical predictions is supported by the excellent agreement of the calculated free-energy barrier value of 16.9 kcal/mol with available experimental value of 16-17 kcal/mol.The present study challenges the widely accepted view which holds that the O2activation catalyzed byα-keto glutamate(α-KG)dioxygenase mainly runs on the quintet PES and provides new insight into the catalytic mechanism ofα-KG dioxygenase and/or other related Fe(Ⅱ)-dependent oxygenase.展开更多
基金supported by the National Natural Science Foundation of China (No. 20702038)
文摘3,3'-Bis(5-(N-(4-hydroxylphenyl)imidomethyl)pyrrol-2-yl)pentane 1 has been synthesized and characterized. The crystal of its methanol complex, 1·(CH3OH)2, belongs to the orthorhombic system, space group Pccn with a = 18.094(2), b = 11.6890(16), c = 13.3629(19) , V = 2826.3(7) 3, Z = 8, C14.5H18N2O2, Mr = 252.31, Dc = 1.186 g/cm3, F(000) = 1080 and μ(MoKα) = 0.080 mm-1. The final R = 0.0662 and wR = 0.1801 for 1908 observed reflections with I 2σ(I), and R = 0.0800 and wR = 0.1948 for all reflections. In the solid state, bridged by included methanol molecules, the molecules of compound 1 form interpenetrated grid structure through N–H···O and O–H···O hydrogen bonds.
基金supported by the National Key R&D Program(No.2021YFD1700100)National Natural Science Foundation of China(Nos.21837001,21273089)+2 种基金the Open Project Fund of the Key Laboratory of the Pesticides and Chemical Biology of Central China Normal University(No.2018-A01)the Fundamental Research Funds for the Central Universitiesthe Fundamental Research Funds for the South-Central University for Nationalities(No.CZW20020)。
文摘The dioxygen activation catalyzed by 4-hydorxylphenyl pyruvate dioxygenase(HPPD)were reinvestigated by using hybrid quantum mechanics/molecular mechanics(QM/MM)approaches at the B3LYP/6-311++G(d,p):AMBER level.These studies showed that this reaction consisted of two steps including the dioxygen addition/decarboxylation and hetero O-O bond cleavage,where the first step was found to be rate-determining.The former step initially runs on a septet potential energy surface(PES),then switches to a quintet PES after crossing a septet/quintet minimum energy crossing point(MECP)5-7M2,whereas the rest step runs on the quintet PES.The reliability of our theoretical predictions is supported by the excellent agreement of the calculated free-energy barrier value of 16.9 kcal/mol with available experimental value of 16-17 kcal/mol.The present study challenges the widely accepted view which holds that the O2activation catalyzed byα-keto glutamate(α-KG)dioxygenase mainly runs on the quintet PES and provides new insight into the catalytic mechanism ofα-KG dioxygenase and/or other related Fe(Ⅱ)-dependent oxygenase.