Selective Conversion of<i>N</i>-Trichloroethoxycarbonyl (Troc) Groupsinto<i>N</i>-Acetyl Groups in thePresence of<i>N</i>-<i>tert</i>-Butoxycarbonyl(Boc) Protecting Groups
作者:Richard R. Schmidt、Xiangming Zhu
DOI:10.1055/s-2003-39405
日期:——
Deprotection of N-trichloroethoxycarbonyl (Troc) groups with zinc in acetic anhydride cleaves also N-tert-butoxycarbonyl (Boc) groups, thus liberating the amino groups, which are immediately N-acetylated. When this reaction is performed in the presence of triethylamine only Troc groups are selectively cleaved as demonstrated for several examples.
Synthesis of an S-linked glycopeptide analog derived from human Tamm–Horsfall glycoprotein
作者:Xiangming Zhu、Tobias Haag、Richard R. Schmidt
DOI:10.1039/b311583f
日期:——
Direct base catalyzed S-glycosylation of a cysteine and a homocysteine containing peptide with O-acetyl protected bromides in DMF-water solution furnished two glycopeptide fragments. The two glycopeptide fragments were linked to the target glycopeptide with two S-glycosyl residues mimicking a part of Tamm-Horsfall glycoprotein.