Compounds of the general formula ##STR1## wherein two of the residues R.sup.1, R.sup.2 and R.sup.3 represent C.sub.10-30 -alkyl residues with at least 8 C-atoms in a straight chain, at least one of these residues being substituted by at least 2 C.sub.1-3 -alkyl residues and the sum of the C-atoms in the two residues being greater than 20; and the third residue is a residue --P(O)(O.sup.-)OR.sup.4 in which R.sup.4 represents a lower-alkyl or C.sub.5-7 -cycloalkyl residue which is substituted by a quaternary ammonium group or a C.sub.5-7 -cycloalkyl residue which contains a di-(lower-alkyl)-substituted nitrogen atom, are useful for the manufacture of colloidal solution systems. The compounds of formula I can be prepared starting from glycerol derivatives as described in more detail in the specification.
1-Methyl 1′-cyclopropylmethyl (MCPM) as an anomeric protecting group
作者:Siu Hong Yu、Dennis M. Whitfield
DOI:10.1016/j.tet.2011.05.133
日期:2011.8
oligosaccharide as a buildingblock with most of its protecting groups exchanged to protecting groups whose cleavage and other manipulations are highly compatible with the functional groups of complex aglycones. For such an approach the reducing end sugar of the building bloc must be protected with a cleavable protecting group during the oligosaccharide synthesis. We demonstrate that the acid labile 1-methyl
Development of new glycosylation methodologies for the synthesis of archaeal-derived glycolipid adjuvants
作者:Dennis M. Whitfield、Siu H. Yu、Chantale J. Dicaire、G. Dennis Sprott
DOI:10.1016/j.carres.2009.10.011
日期:2010.1
boron trifluoride-trifluoroethanol (BF(3) x TFE(2)) in dichloromethane. This promoter system allows for the use of peracetyl alkyl(aryl)thioglycosides that are available in high yield from inexpensive disaccharide starting materials by promoting clean glycosylation reactionsfrom which pure product can be easily isolated. Conventional glycosylation using NIS-silver trifluoromethanesulfonate (AgOTf) leads