(E)-3-(3,4-Di-(2,3,4,6-tetra-O-acetyl-β-d-glucopyranosyloxy)phenyl) Acrylic Acid

Phenolic acids are widely known for their antioxidant and biological properties, which make them attractive scaffolds for structural modification. In this short note, we report the synthesis of a new 3,4-di-glucosylated caffeic acid analogue. The (E)-3-(3,4-di-(2,3,4,6-tetra-O-acetyl-β-d-glucopyranosyloxy)phenyl) acrylic acid was obtained through a two-step synthesis, starting with a phase-transfer-catalyzed glycosylation of 3,4-dihydroxybenzaldehyde with 2,3,4,6-tetra-O-acetyl-α-d-glucopyranosyl bromide followed by a Dobner-modified Knoevenagel condensation. Consistent with the 2-O-acetyl neighbouring participation and the resulting Walden-type inversion at the anomeric centre, both glucopyranosyl units were assigned the β-configuration.