A new stereoselective approach to a selectively protected derivative of d-pinitol and its evaluation as α-l-rhamnopyranose mimetic

The synthesis of 3,5-di-O-benzyl-d-pinitol has been stereoselectively accomplished through intramolecular aldolization of 2,6-di-O-benzyl-4-O-methyl-l-lyxo-hexos-5-ulose followed by reduction with NaBH(OAc)3. Computational analysis [DFT calculations at the B3LYP/6-31G(d) level] suggests that d-pinitol in water largely prefers the conformation corresponding to the 1C4 one of a α-l-rhamnopyranoside unit, being thus a good candidate for its mimicking.