Epimerization-Free Block Synthesis of Peptides from Thioacids and Amines with the Sanger and Mukaiyama Reagents
作者:David Crich、Indrajeet Sharma
DOI:10.1002/anie.200805782
日期:2009.3.16
reaction of C‐terminal thioacids derived from protected amino acids and peptides with the Sanger reagent and other electron‐deficient aryl halides in the presence of a free amine immediately form a peptide bond with the amine. This essentially epimerization‐free method was used for the 4+4 block synthesis of a hindered octapeptide (see scheme; Boc, Pbf, and Trt are protectinggroups).
Structural modification of S-trityl-L-cysteine. Preparation of some S-(substituted trityl)-L-cysteines and dipeptides of S-trityl-L-cysteine
作者:Kwang Yuen Zee-Cheng、C. C. Cheng
DOI:10.1021/jm00271a005
日期:1972.1
Design, synthesis, and evaluation of novel bifunctional iron-chelators as potential agents for neuroprotection in Alzheimer’s, Parkinson’s, and other neurodegenerative diseases
Several novel antioxidant-iron chelators bearing 8-hydroxyoxyquinoline moiety were synthesized, and various properties related to their iron chelation, and neuroprotective action were investigated. All the chelators exhibited strong iron(III) chelating and high antioxidant properties. Chelator 9 (HLA20). having good permeability into K562 cells and moderate selective MAO-B inhibitory activity (IC50 110 muM), displayed the hightest protective effects against differentiated P19 cell death induced by 6-hydroxydopamine. EPR studies suggested that Chelator 9 also act as radical scavenger to directly scavenge hydroxyl radical. (C) 2004 Elsevier Ltd. All rights reserved.