Synthesis of a phenylpropanoid glycoside, Osmanthuside B6

2-Ac-Osmanthuside B6 [2-(4-hydroxyphenyl)ethyl 2-O-acetyl-3-O-(α-l-rhamnopyranosyl)-6-O-(4-hydroxycinnamoyl)-β-d-glucopyranoside, 8], a derivative of Osmanthuside B6, was synthesized in 7 steps with the goal of preparing Osmanthuside B6. Surprisingly, it was found that the 2-acetyl group in the glucose ring of the compound 7, 1-O-[2-(4-allyloxyphenyl)ethyl]-2-O-acetyl-3-O-(2,3,4-tri-O-acetyl-α-l-rhamnopyranosyl)-6-O-(4-acetoxycinnamoyl)-β-d-glucopyranoside, could not be removed by conventional deacetylation procedures.