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151.
组蛋白去乙酰化酶(HDAC)对染色质分布和基因调节起着重要的作用,也是治疗癌症和其它疾病的新靶点.羟肟酸类抑制剂是目前研究最多的组蛋白去乙酰化酶抑制剂.应用比较分子力场(CoMFA)法对一系列磺胺基羟肟酸类HDAC抑制剂进行了结构活性关系研究,得到的模型具有较高的交叉验证系数(q2=0.704).并在此基础上,建立了非交叉验证的偏最小二乘分析(PLS)模型.用该模型对随机选择的6个化合物组成的测试集进行了预测,得到了令人满意的结果,所建模型具有良好的预测能力.本研究对于设计高活性的HDAC抑制剂及抗癌药物都有指导意义.  相似文献   
152.
The title compound, crystallizes in the triclinic space group witha=8.232(4),b=9.159(2),c=10.230(3)Å. =74.07(3)°, =72.50(4)°, =63.65(3)° andZ=2. The structure was solved by direct methods and refined by full matrix least squares methods toR=0.054 for 1817 observed reflections. The plane containing the nitrogen and sulfur atoms is perpendicular to the aromatic plane. One of the S–O bonds in each methanesulfonyl group is in nearly eclipsed conformation with the N–C bond.  相似文献   
153.
Aluminum complexes supported by a sulfonamide/Shiff base ligand are described. Reaction of AlMe3 with 1 equiv of ligand 1, gives methyl aluminum complex 2, and aluminum complex 3 is prepared by the reaction of complex 2 with 1 equiv of benzyl alcohol. Experimental results show that complex 3 is an efficient initiator for the ring-opening polymerization of lactide in controlled fashion, yielding polymers with expectative molecular weight and low polydispersity indexes. Furthermore, the complex 3 has isotactic selectivity for the ring-opening polymerization of rac-lactide.  相似文献   
154.
Sulfonamide imprinted polymers using co-functional monomers   总被引:1,自引:0,他引:1  
Molecular imprinted polymers (MIPs) prepared using combination of acrylamide (ACM) and 4-vinylpyridine (4-Vpy) as co-functional monomers exhibited efficient recognition properties in both organic and aqueous media as HPLC stationary phase. The results indicate that amide and pyridine groups in functional monomers formed strong hydrogen-bonding interaction with the template molecule, and specific recognition sites were created within the polymer matrix during the imprinting process. When sulfamethoxazole (SMO) was used as template, a MIP prepared in a polar organic solvent (acetonitrile) using the combination of ACM and 4-Vpy showed better recognition of template than the polymer prepared in the same solvent using the combination of acidic monomer (methacrylic acid) and basic monomer 4-Vpy. On the contrary, when sulfamethazine (SMZ) was used as template, a MIP prepared using the combination of methacrylic acid (MAA) and 4-Vpy showed better recognition of template than the polymer prepared using the combination of ACM and 4-Vpy. Our results indicate that in organic media the degree of retention of the sample molecules on the imprinted polymers was controlled by the hydrogen-bonding interaction between the sample molecules and the polymer, while in aqueous media it was determined to a considerable extent by hydrophobic interactions. In both media the shape, size and the electronic structure of the template molecule were all-important factors in the recognition process.  相似文献   
155.
The N-acylation of sulfonamides with carboxylic acid anhydrides in the presence of Lewis acids is described. Several Lewis acids such as BF3·Et2O, ZnCl2, MoCl5, TiCl4, B(C6F5)3, Sc(OTf)3 and I2 were found to catalyze the reaction efficiently to furnish the N-acylated products in good yields under solvent-free conditions. The reactions of various sulfonamides were studied with different carboxylic acid anhydrides including the less reactive benzoic and pivalic anhydrides, in the presence of 3 mol % ZnCl2 as the catalyst. Carboxylic acids were also successfully used as acylating agents via the mixed anhydride method.  相似文献   
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