Direct glycosylation of protected O-tritylserine esters and oligopeptides
摘要:
N-Finoc-3-O-Tr-L-serine methyl and benzyl esters, as well as a tripeptide FmocAlaSeI(Tr)GlyOBn were directly glycosylated by 3,4,6-tri-O-acetyl-1,2-O-(1-cyanoethylidene)-alpha-D-galactopyranose in the presence of TrClO(4) in dichloromethane, yielding 32-57% of N-Fmoc-3-O-(2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl)-L-serine esters and the corresponding tripeptide.
Friedel–Crafts catalysts as assistants in the tritylation of less reactive hydroxyls
作者:Roberta Bernini、Maurizio Maltese
DOI:10.1016/j.tetlet.2010.05.144
日期:2010.8
Less reactive hydroxyls, such as those present in secondary alcohols and in some primary alcohols, phenols and carboxylic acids, were easily tritylated with the homogeneous assistance of equimolar quantities of chlorides of di- and trivalent metals in aprotic solvents. The metal ions allowed both high concentration of the effective reagent triphenylmethylcarbenium ion and mobilisation of the hydroxyl
Direct glycosylation of protected O-tritylserine esters and oligopeptides
作者:Andrzej Rajca、Manfred Wiessler
DOI:10.1016/0008-6215(95)00097-d
日期:1995.9
N-Finoc-3-O-Tr-L-serine methyl and benzyl esters, as well as a tripeptide FmocAlaSeI(Tr)GlyOBn were directly glycosylated by 3,4,6-tri-O-acetyl-1,2-O-(1-cyanoethylidene)-alpha-D-galactopyranose in the presence of TrClO(4) in dichloromethane, yielding 32-57% of N-Fmoc-3-O-(2,3,4,6-tetra-O-acetyl-beta-D-galactopyranosyl)-L-serine esters and the corresponding tripeptide.