An anionic inositol phosphate glycan pseudotetrasaccharide exhibits high insulin-mimetic activity in rat adipocytes

Inositol phosphate glycan pseudotetrasaccharides consisting of man-(1-6)-man-(1-4)-glcN-(,β1-6)-myo-inositol-1,2-cyclic phosphate possessing a sulfate group at either O-6 (compounds 3,β) or O-2 (compounds 4,β) of the terminal mannose have been prepared. Compound 4 was able to stimulate lipogenesis in native rat adipocytes to 78% of the maximal insulin response (MIR) with an EC₅₀ of 1.1 μM. The other compounds exhibited lower maximal stimulations (47–63% MIR) and higher EC₅₀ values (9.5–10.6 μM).