Methods and compositions for treating amyloid-related diseases
申请人:Kong Xianqi
公开号:US20060223855A1
公开(公告)日:2006-10-05
Methods, compounds, pharmaceutical compositions and kits are described for treating or preventing amyloid-related disease.
描述了用于治疗或预防与淀粉样蛋白相关疾病的方法、化合物、药物组合物和试剂盒。
Electrostatic Repulsion and Hydrogen-Bonding Interactions in a Simple<i>N</i>-Aryl-<scp>L</scp>-valinamide Organocatalyst Control the Stereoselectivity in Asymmetric Aldol Reactions
作者:Yuya Tanimura、Kenji Yasunaga、Kaori Ishimaru
DOI:10.1002/ejoc.201301138
日期:2013.10
A novel stereocontrol method for asymmetric aldol reactions of aldehydes with ketones is described. The stereoselectivity of the products is controlled by the electrostaticrepulsion and hydrogen-bonding interactions of an N-aryl-L-valinamide catalyst. The use of this catalyst in a cross-aldol reaction allows easy access to bioactive 3-cyclohexanone-3-hydroxy-2-oxindole with excellent diastereo- (syn/anti
Controlling the sign and magnitude of screw-sense preference from the C-terminus of an achiral helical foldamer
作者:Bryden A. F. Le Bailly、Jonathan Clayden
DOI:10.1039/c4cc03261f
日期:——
The global screw-sense preference of an achiral helical oligomer is best controlled from its C-terminus by a single Ala monomer.
一个无手性螺旋寡聚体的全球螺旋方向偏好最好通过其C-末端由单个丙氨酸单体控制。
Reversal of Selectivity in Acetate Aldol Reactions of <i>N</i>-Acetyl-(<i>S</i>)-4-isopropyl-1-[(<i>R</i>)-1-phenylethyl]imidazolidin-2-one
作者:Gopal L. Khatik、Varun Kumar、Vipin A. Nair
DOI:10.1021/ol300949s
日期:2012.5.18
the exo- and endocyclic chiral centers of an imidazolidinone-based auxiliary were investigated in the perspective of acetate aldolreactions. The reversal in diastereoselectivity was accomplished by lithium and titaniumenolatereactions, which proceed through proposed open and closed transitions states, respectively. The aldol adducts were used in the stereoselective synthesis of fluoxetine.
Synthetic and mechanistic insight into nosylation of glycine residues
作者:Nicolai Stuhr-Hansen、Theis Ivan Sølling、Kristian Strømgaard
DOI:10.1039/c3ob00014a
日期:——
The Fukuyama–Mitsunobu alkylation procedure is widely used to introduce alkyl substituents to amino groups in general and N-alkylation of peptides in particular. Here we have investigated the procedure in detail for N-alkylation of peptides with N-terminal glycine residues, based on the observation that standard conditions lead to substantial bis-nosylation of the glycine amino group. A systematic evaluation of this observation was carried out and it was demonstrated that for peptides with alanine, β-alanine or γ-aminobutyric acid (GABA) as N-terminal residues mono-nosylation was observed under the same conditions. Moreover, bis-nosylation was independent of the type of resin, neighboring amino acid and nature of the peptide. Calculations suggest that the reason for the bis-nosylation is the fact that the deprotonated mono-nosyl species is particularly stable in the case of the terminal Gly residue because the N− residue can become closer to the SO2 unit. Finally, the mono-nosylated N-terminal glycine could be obtained by careful optimization of the procedure, adding only one equivalent of 2-nitrobenzenesulfonyl chloride.
Fukuyama-Mitsunobu 烷基化程序被广泛用于在氨基上引入烷基取代基,特别是肽的 N-烷基化。在此,我们根据标准条件会导致甘氨酸氨基发生大量双烷基化的观察结果,详细研究了该程序对具有 N 端甘氨酸残基的肽进行 N- 烷基化的过程。我们对这一观察结果进行了系统评估,结果表明,在相同条件下,以丙氨酸、β-丙氨酸或γ-氨基丁酸(GABA)为 N 端残基的肽也会发生单烷基化。此外,双糖基化与树脂类型、邻近氨基酸和肽的性质无关。计算结果表明,双糖基化的原因是,在末端 Gly 残基的情况下,去质子化的单糖基物种特别稳定,因为 N-残基可以变得更接近 SO2 单元。最后,通过仔细优化程序,只加入一个当量的 2-硝基苯磺酰氯,就可以得到单 Nosyl 化的 N 端甘氨酸。