A facile and convenient synthesis of disarmed glycosyl fluorides using in situ-generated iodine monofluoride (see Ref. 1)
作者:G. Mugunthan、K. P. Ravindranathan Kartha
DOI:10.1016/j.tetlet.2012.08.024
日期:2012.10
A facile and convenient synthesis of disarmed glycosyl fluorides using in situ-generated iodine monofluoride is reported. The method is tolerant to most of the popularly used protecting groups and gives exclusively the α-anomeric product in very good yields.
A new method of anomeric protection and activation based on the conversion of glycosyl azides into glycosyl fluorides
作者:Wolfgang Bröder、Horst Kunz
DOI:10.1016/0008-6215(93)84071-d
日期:1993.10
Glycosyl azides provide reliable anomeric protection stable to conditions for hydrolytic removal of ester groups, for reductive opening or release of acetalic diol protection, for the introduction of ether-type protection, and for glycosylation processes. The utility of this anomeric protection is further enhanced as glycosyl azides may be converted into glycosyl fluorides, which can be activated for
α-Tocopheryl disaccharides such as β-gentiobioside, β-maltoside, β-cellobioside, β-lactoside, β-melibioside, and β-isomaltoside were synthesized by biological and chemical glycosylation, and their inhibitory effects on superoxide generation from rat neutrophils were examined.
Studies on sialic acids. Part XXII. Synthesis of 6-O-(5-acetamido-3,5-dideoxy-D-glycero-.ALPHA.- and -.BETA.-D-galacto-nonuropyranosonic acid)-(2.RAR.6)-O-.BETA.-D-galactopyranosyl-(1.RAR.4)-1-(5-cholesten-3.BETA.-yloxy)-.BETA.-D-glucopyranose.
6-O-(5-Acetamido-3, 5-dideoxy-D-glycero-α- and -β-D-galacto-nonulopyranosylonic acid)-(2→6)-O-β-D-galacto-pyranosyl-(1→4)-1-(5-cholesten-3β-yloxy)-β-D-glucopyranose was synthesized under various conditions through a Koenigs-Knorr-like reaction. The stereochemistry of the products was confirmed by analysis of the nuclear magnetic resonance and circular dichroism spectra.
Peracetylated alpha-glycopyranosyl fluorides of di- and tri-saccharides are obtained in good yields by treatment of the corresponding peracetylated di- and tri-saccharides with pyridinium poly(hydrogen fluoride). The interglycosidic bonds are not cleaved by the reagent.