Preparation of orthogonally protected chitosan oligosaccharides: observation of an anomalous remote substituent effect.
Orthogonally protected chitosan tetrasaccharides were synthesized in a convergent fashion by trichloroacetimidate activation. The anomeric substituent at the reducing end of the disaccharide acceptor has a remarkably strong influence on glycosidic coupling; a thiophenyl-substituted disaccharide was observed to be an unusually poor glycosyl acceptor in comparison with the corresponding allyloxy-substituted disaccharide.
Liew
Siong-Tern
ST
Department of Chemistry, Purdue University, West Lafayette, IN 47907-1393, USA.
Wei
Alexander
A
D002686:Chitin / Q000031:analogs & derivatives* / Q000138:chemical synthesis* / Q000737:chemistry; D048271:Chitosan; D009682:Magnetic Resonance Spectroscopy; D009844:Oligosaccharides / Q000138:chemical synthesis* / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization; D013329:Structure-Activity Relationship
D009844:Oligosaccharides; D002686:Chitin; D048271:Chitosan