Three Types of Induced Tryptophan Optical Activity Compared in Model Dipeptides: Theory and Experiment
作者:Jana Hudecová、Jan Horníček、Miloš Buděšínský、Jaroslav Šebestík、Martin Šafařík、Ge Zhang、Timothy A. Keiderling、Petr Bouř
DOI:10.1002/cphc.201200201
日期:2012.8.6
dipeptides c‐(Trp‐X) (where X=Gly, Ala, Trp, Leu, nLeu, and Pro) are analyzed on the basis of experimental spectra and density functional theory (DFT) computations. The results provide valuable insight into the molecular conformational and spectroscopic behavior of Trp. Whereas the ECD is dominated by Trp π–π* transitions, VCD is dominated by the amide modes, well separated from minor Trp contributions. The
Urea-cored peptides for anion binding and vesicle formation
作者:Ishanki Bhardwaj、Rachit Sapra、V. Haridas
DOI:10.24820/ark.5550190.p009.876
日期:——
Urea and urea-triazole cored peptides were synthesized and characterized. These compounds were analyzed for their potency to sense anions such as F – , Cl – , Br – , I – , H2PO4 – and HSO4 – by UV-vis and H NMR spectroscopy. Urea-cored compounds showed very weak binding, while the ureatriazole containing compound showed high binding towards H2PO4 – and HSO4 – . The urea-triazole containing compound
HMDO-Promoted Peptide and Protein Synthesis in Ionic Liquids
作者:Jianli Duan、Yao Sun、Hao Chen、Guofu Qiu、Haibing Zhou、Ting Tang、Zixin Deng、Xuechuan Hong
DOI:10.1021/jo400797t
日期:2013.7.19
Hexamethyldisiloxane (HMDO) has been developed to efficiently promote the metal-free direct coupling of an amino function of one cysteine-free peptide or protein and a C-terminal thioester of the second peptide in ionic liquids. The amide-coupling reaction proceeds smoothly under mild conditions to afford the corresponding products in good to excellent yields (63-94%). Peptide couplings were also achieved using in-situ-generated thioesters by the thioesterification of oxo esters.
A [3,3] Sigmatropic and Novel Ipso [3,3] Sigmatropic Rearrangement of 1-Hydroxyindole Chemistry