Synthesis of Allyl 3-Deoxy-<scp>d</scp>-<i>manno</i>-2-octulopyranosidic Acid 4- and 5-Phosphates

Abstract

Abstract Allyl glycosides (ketosides) of pyranosidic 3-deoxy-d-manno-2-octulosonic acid (Kdo), phosphorylated at either positions 4 or 5 were synthesized with the aim to study the biological properties of phosphorylated Kdo. The α and β-allyl glycosides prepared from a pyranosidic fluoride of diisopropylidene Kdo were protected at the 7- and 8-positions, and then O-phosphorylated at the 4- or 5-position by the phosphoramidite procedure. Separation of the positional isomers followed by deprotection afforded four compounds in pure states.