Synthesis of new anhydro and branched-chain cyclitols

Starting from d-glucose and d-(−)-quinic acid (5) (1S,5R,6S)-5-azido-6-benzyloxycyclohex-2-en-1-ol (3), and the structurally related α,β-unsaturated alcohols 7 and 8, respectively, were prepared. They have been transformed, by treatment with 3-chloroperoxybenzoic acid, into (1R,2S,3R,5S,6R)-3-azido-2-benzyloxy-5,6-epoxycyclohexane-1-ol (4) and the two diastereoisomeric 4,5-isopropylidenedioxycyclohexane-1-ols 9 and 10. Thermal Claisen rearrangement of the allylic alkcohols 3, 7 and 8 resulted in the functionalized branched-chain cyclohexenyl acetamides 12, 13 and 14, respectively. The prepared new cyclitols are useful starting materials for further derivatization to obtain novel enzyme-inhibitors, including phosphorylated cyclitols with “second-messenger” properties.