本实验室新近提出按氢分类分子电性距离矢量(H-MEDV),用于对110个烷基苯气相色谱保留指数和54个二取代苯液相色谱容量因子进行结构表征,运用多元线性回归(multiple linear regression,MLR)以建立定量结构色谱保留关系(QSRR)模型,同时利...本实验室新近提出按氢分类分子电性距离矢量(H-MEDV),用于对110个烷基苯气相色谱保留指数和54个二取代苯液相色谱容量因子进行结构表征,运用多元线性回归(multiple linear regression,MLR)以建立定量结构色谱保留关系(QSRR)模型,同时利用逐步回归结合统计检测对模型变量作筛选,建模计算值复相关系数(R_(cum))、留一法(leave-one-out,LOO)交互校验(cross-validation,CV)复相关系数(Q_(LOO)),对上述样本分别为0．9950、0．9937和0．9648、0．9530。研究结果表明,H-MEDV能较好表征该类分子结构信息,值得进一步推广。展开更多
Holographic quantitative structure activity relationship(HQSAR) is an emerging QSAR technique with the combined application of molecular hologram, which encoded the frequency of occurrence of various molecular fragme...Holographic quantitative structure activity relationship(HQSAR) is an emerging QSAR technique with the combined application of molecular hologram, which encoded the frequency of occurrence of various molecular fragment types, and the subsequent partial least squares(PLS) regression analysis. In this paper, the acute toxicity data to the guppy( poecilia reticulata) for a series of 56 substituted benzenes, phenols, aromatic amines and nitro aromatics were subjected and this resulted in a model with a high predictive ability. The influence of fragment size and fragment distinction parameters on the quality of HQSAR model was investigated. The robustness and predictive ability of the model were also validated by leave one out (LOO) cross validation procedure and external testing data set.展开更多
The crystal structure of the title compound, diethyl 4,5-di（thienyl）-3,6-bis（trime- thylsilyl）phthalate （C26H3404S2Si2, Mr = 530.83）, has been determined by single-crystal X-ray diffraction. The crystal belongs ...The crystal structure of the title compound, diethyl 4,5-di（thienyl）-3,6-bis（trime- thylsilyl）phthalate （C26H3404S2Si2, Mr = 530.83）, has been determined by single-crystal X-ray diffraction. The crystal belongs to the orthorhombic system, space group Pccn with a = 43.008（5）, b = 10.9000（12）, c = 11.9357（14） A, V= 5595.3（11） A3, Z = 8, F（000） = 2256, Dc= 1.260 mg/m3, p = 0.305 mm-1, T = 113（2） K, S = 1.090, R = 0.0413 and wR = 0.0969 for 5952 observed reflections with 1 〉 2o（/）. The benzene ring system is planar and makes dihedral angles of 63.7（2） and 72.5（4） with the two thienyl rings A （C（23）-C（26）, S（2）） and B （C（19）-C（22）, S（1））, respectively. The UV-vis absorption and fluorescence of the title compound were discussed. The molecular structure of the title compound has been optimized using DFT method at the B3LYP/6-31G（d） level. The computational results showed that the optimized geometer parameters are consistent well with the experiment data. The vertical ionization potential, vertical electron affinity and frontier orbitals were also discussed.展开更多
基金This work was financially supported by the National Natural Science Foundation of China(40906076)the Shandong Provincial Natural Science Fund(ZR2009CZ016)
文摘本实验室新近提出按氢分类分子电性距离矢量(H-MEDV),用于对110个烷基苯气相色谱保留指数和54个二取代苯液相色谱容量因子进行结构表征,运用多元线性回归(multiple linear regression,MLR)以建立定量结构色谱保留关系(QSRR)模型,同时利用逐步回归结合统计检测对模型变量作筛选,建模计算值复相关系数(R_(cum))、留一法(leave-one-out,LOO)交互校验(cross-validation,CV)复相关系数(Q_(LOO)),对上述样本分别为0．9950、0．9937和0．9648、0．9530。研究结果表明,H-MEDV能较好表征该类分子结构信息,值得进一步推广。
文摘Holographic quantitative structure activity relationship(HQSAR) is an emerging QSAR technique with the combined application of molecular hologram, which encoded the frequency of occurrence of various molecular fragment types, and the subsequent partial least squares(PLS) regression analysis. In this paper, the acute toxicity data to the guppy( poecilia reticulata) for a series of 56 substituted benzenes, phenols, aromatic amines and nitro aromatics were subjected and this resulted in a model with a high predictive ability. The influence of fragment size and fragment distinction parameters on the quality of HQSAR model was investigated. The robustness and predictive ability of the model were also validated by leave one out (LOO) cross validation procedure and external testing data set.
基金supported by the National Natural Science Foundation of China(No.21102099)
文摘The crystal structure of the title compound, diethyl 4,5-di（thienyl）-3,6-bis（trime- thylsilyl）phthalate （C26H3404S2Si2, Mr = 530.83）, has been determined by single-crystal X-ray diffraction. The crystal belongs to the orthorhombic system, space group Pccn with a = 43.008（5）, b = 10.9000（12）, c = 11.9357（14） A, V= 5595.3（11） A3, Z = 8, F（000） = 2256, Dc= 1.260 mg/m3, p = 0.305 mm-1, T = 113（2） K, S = 1.090, R = 0.0413 and wR = 0.0969 for 5952 observed reflections with 1 〉 2o（/）. The benzene ring system is planar and makes dihedral angles of 63.7（2） and 72.5（4） with the two thienyl rings A （C（23）-C（26）, S（2）） and B （C（19）-C（22）, S（1））, respectively. The UV-vis absorption and fluorescence of the title compound were discussed. The molecular structure of the title compound has been optimized using DFT method at the B3LYP/6-31G（d） level. The computational results showed that the optimized geometer parameters are consistent well with the experiment data. The vertical ionization potential, vertical electron affinity and frontier orbitals were also discussed.
