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Saccharides basic conditions

Furthermore, simplicity is the driving force to further reduce the final coupling and deprotection steps on the dendritic surface to obtain the desired (oligo)saccharide-containing dendritic scaffolds. Much research has been focused on synthetic approaches in aqueous solution. As a result, reductive amination is now widely used under acidic and basic conditions, because it... [Pg.209]

The popularity of the poly(saccharide) derivatives as chiral stationary phases is explained by the high success rate in resolving low molecular mass enantiomers. It has been estimated that more than 85% of all diversely structured enantiomers can be separated on poly(saccharide) chiral stationary phases, and of these, about 80% can be separated on just four stationary phases. These are cellulose tris(3,5-dimethylphenyl carbamate), cellulose tris(4-methylbenzoate), amylose tris(3,5-dimethylphenyl carbamate), and amylose tris(l-phenylethyl carbamate). Typically, n-hexane and propan-2-ol or ethanol mixtures are used as the mobile phase [111]. Both the type and concentration of aliphatic alcohols can affect enantioselectivity. Further mobile phase optimization is restricted to solvents compatible with the stationary phase, such as ethers and acetonitrile, as binary or ternary solvent mixtures, but generally not chloroform, dichloromethane, ethyl acetate, or tetrahydrofuran. Small volumes of acidic (e.g. tri-fluoroacetic acid) or basic (n-butylamine, diethylamine) additives may be added to the mobile phase to minimize band broadening and peak tailing [112]. These additives, however, may be difficult to remove from the column by solvent rinsing to restore it to its original condition. [Pg.811]


See other pages where Saccharides basic conditions is mentioned: [Pg.889]    [Pg.343]    [Pg.89]    [Pg.381]    [Pg.508]    [Pg.84]    [Pg.684]    [Pg.64]    [Pg.52]    [Pg.507]    [Pg.156]    [Pg.209]    [Pg.288]    [Pg.192]    [Pg.227]    [Pg.435]    [Pg.440]    [Pg.1551]    [Pg.256]    [Pg.444]    [Pg.424]   
See also in sourсe #XX -- [ Pg.281 , Pg.282 , Pg.283 ]

See also in sourсe #XX -- [ Pg.46 , Pg.281 , Pg.282 , Pg.283 ]




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Basic conditions

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