Asymmetric Organocatalytic Efficiency of Synthesized Chiral β-Amino Alcohols in Ring-Opening of Glycidol with Phenols
作者:Tarik Aral、Mehmet Karakaplan、Halil Hoşgören
DOI:10.1007/s10562-012-0814-4
日期:2012.6
A series of novel chiral β-amino alcohols 3–5 and 7–10 were synthesized by regioselective ring opening of epoxides and chiral amines with a straightforward method in high yields (up to 99 %). Kineticresolution of racemic glycidol with phenols was achieved by using chiral amino alcohols as organocatalysts. Amino alcohols 5,8 and 10 exhibited the highest enantioselectivities with p-cresol, phenol, and
Synthesis of new diaza-18-crown-6 ethers derived from trans-(R,R)-1,2-diaminocyclohexane and investigation of their enantiomeric discrimination ability with amino acid ester salts
achieved. Enantiomeric discrimination of these macrocycles against aminoacid methyl estersalts was examined by 1H NMR titration method. They exhibit strong binding ability and some of them show a very high enantioselectivity towards aminoacidesters, corresponding to 5.37 kJ/mol of binding energy difference in CDCl3 at 25 °C. Computational modelling showed parallel results with experimental calculations
合成了四个C 2对称的diaza -18-crown-6醚,这些醚衍生自反式-(R,R)-1,2-二氨基环己烷,其甲基,苯基和苯氧甲基部分连接在冠环的立体中心上。通过1 H NMR滴定法检查了这些大环与氨基酸甲酯盐的对映体区别。它们具有很强的结合能力,其中一些对氨基酸酯具有很高的对映选择性,相当于CDCl 3中的结合能差为5.37 kJ / mol。在25°C下。计算模型显示出与实验计算结果平行的结果,从而提供了对分子识别模式和宿主与客人之间结合位点的详细了解。
Synthesis and crystal structure of a chiral lactam and three amino alcohols as potential protein tyrosine phosphates 1B inhibitors
Chiral lactam 2 and three chiral 3-amino alcohols 3-5 have been synthesized and characterized by Sspectroscopic techniques. Regioselective ring opening reaction of chiral styrene oxide by an amine nucle-ophile was confirmed by X-ray diffraction data. Ligand 2-4 crystallizes in the tetragonal, orthorhombic and tetragonal crystal lattice system respectively. Ligands 2-6 have been used as potential inhibitors for protein tyrosine phosphatase 1B enzyme (PTP1B). The potential inhibitor effect of these molecules to the target protein was investigated by Dock and molecular dynamics calculations. Dock score analysis and Lipinski parameters suggested that ligands 1,2,4-6 are potential inhibitors towards PTP1B, thus indicating that the residues Arg24, Arg254 and Met258, Asp29 in the second active site of PTP1B are essential for the high selectivity of inhibitors. The results indicate that the polar hydrogen bonding interacts with Asp29, Gln102, and the amino acid residues of PTP1B are responsible for governing inhibitory potency of ligands 1-6. (C) 2017 Elsevier Ltd. All rights reserved.