Process for the production of perbenzylated 1-0-glycosides

Process for the production of perbenzylated 1-O-glycosides of general formula I

• 5
• in which
• sugar1 is a monosaccharide that is functionalized in 1-OH-position,
• R represents benzyl,
• n means 2, 3 or 4,
• X means —O—, —S—, —COO—or —NH—
• and
• L means a straight-chain, branched, saturated or unsaturated C1-C30 carbon chain, which optionally is interrupted by 1-10 oxygen atoms, 1-3 sulfur atoms, 1-2 phenylene groups, 1-2 phenylenoxy groups, 1-2 phenylenedioxy groups, a thiophene radical, pyrimidine radical or pyridine radical, and/or optionally is substituted with 1-3 phenyl groups, 1-3 carboxyl groups, 1-5 hydroxy groups, 1-5 O—C1-C7 alkyl groups, 1-3 amino groups, 1-3 CF3 groups or 1-10 fluorine atoms
• or their salts, characterized in that
• a perbenzylated 1-OH-sugar of general formula II
• 6
• in which sugar1, R and n have the indicated meaning, is reacted with an alkylating reagent of general formula (III)
• Nu—L—X—Sg (III),
• in which Nu means a nucleofuge, L and X have the above-mentioned meaning, and Sg represents a protective group, in an organic solvent in the presence of a base and optionally a phase transfer catalyst at a temperature of 0-50° C., then the protective group is cleaved off, and the reaction product that is obtained is optionally converted into a salt.