Synthesis of Hyaluronic Acid Oligomers using Chemoselective and One-Pot Strategies

An efficient synthetic strategy toward a hyaluronic acid (HA) tri-, penta-, and heptamer having a glucosamine-reducing end is reported. The synthesis is based on a glucuronate ester thioglycoside and a trifluoro-N-phenylimidate glucosamine building block. The HA-fragments are synthesized using an S-phenyl GlcN-GluA building block through a combination of chemoselective and one-pot condensation strategies.