A convenient one-pot synthesis of (R)-2-amino-3,3,3-trifluoro-2-methyl-N-phenylpropanamide derivatives
摘要:
A convenient one-pot synthesis of enantiopure (R)-2-amino-3,3,3-trifluoro-2-methyl-N-phenylpropanamide derivatives has been developed. The key step in this synthetic methodology turned out to be the amide formation in which (R)-2-amino-3,3,3-trifluoro-2-methylpropanoic acid hydrochloride was simultaneously protected and activated by Vilsmeier reagent. (C) 2012 Elsevier Ltd. All rights reserved.
The chiral α-trifluoromethylalanine is shown to induce and control the screw-sense preference of short Aib oligomers. Due to the electronic properties of the CF3 group, the screw-sense is inversed compared to that induced by its non-fluorinated isosteric l-α-MeVal analogue. It also plays the role of 19F NMR reporter allowing the easy determination of both the magnitude of the screw-sense preference
A useful fluorinated NMRprobe: α-Quaternarized (R)-α-trifluoromethylalanine (α-TfmAla) is a good tool for providing convenient and accurate 19F NMR-based monitoring of trypsin proteolytic activity and increases resistance towards pepsin degradation.
一种有用的氟化 NMR 探针:α-季铵化 ( R )-α-三氟甲基丙氨酸 (α-TfmAla) 是一种很好的工具,可方便、准确地基于19 F NMR 监测胰蛋白酶蛋白水解活性并增加对胃蛋白酶降解的抵抗力。
Bimodal use of chiral <i>α</i>‐Trifluoromethylalanine in Aib Foldamers: study of the position impact towards the helical screw‐sense preference
Introduction of a chiral α-trifluoromethylalanine residue into Aib oligomers proved its effectiveness as a bimodal moiety, acting both as controller and 19F NMR reporter of the helical screw-sense preference. By varying its position along the chain and the nature of the C-terminal capping, our study revealed the stereoelectronic properties of the CF3 group enabling the control of the helical conformation
将手性α -三氟甲基丙氨酸残基引入 Aib 低聚物中,证明了其作为双峰部分的有效性,既充当螺旋感应偏好的控制器又充当19 F NMR 报道分子。通过改变其沿链的位置和 C 末端封端的性质,我们的研究揭示了 CF 3基团的立体电子特性,能够控制螺旋构象。
Synthesis of protected enantiopure (R) and (S)-α-trifluoromethylalanine containing dipeptide building blocks ready to use for solid phase peptide synthesis
synthetic amino acid by the strong electron withdrawing trifluoromethyl group, the peptide coupling on this position is a challenge. In order to provide a robust synthetic methodology for the incorporation of enantiopure (R)- and (S)-α-trifluoromethylalanines into peptides, we report herein the preparation of dipeptides ready to use for solidphasepeptidesynthesis. The difficult peptide coupling on the
A convenient one-pot synthesis of enantiopure (R)-2-amino-3,3,3-trifluoro-2-methyl-N-phenylpropanamide derivatives has been developed. The key step in this synthetic methodology turned out to be the amide formation in which (R)-2-amino-3,3,3-trifluoro-2-methylpropanoic acid hydrochloride was simultaneously protected and activated by Vilsmeier reagent. (C) 2012 Elsevier Ltd. All rights reserved.