Diastereoselective Synthesis of D- and L-myo-Inositol 3,4,5,6-Tetrakisphosphates from D-Glucose via Dihydroxylation of (+)-Conduritol B Derivatives

Practical synthesis of (−)-1-amino-1-deoxy-myo-inositol from achiral precursors

A new synthesis of enantiomerically pure 1-amino-1-deoxy-myo-inositol is reported. The route described employs p-benzoquinone, an achiral compound, as the starting material to give conduritol B tetraacetate in three steps. Kinetic resolution of this compound using a palladium catalyst with a chiral ligand allows access to a conduritol B tetraester in high enantiomeric excess. This compound is transformed into tetrabenzyl conduritol B epoxide, which is regioselectively opened with azide to give the key azidocyclitol. Final transformation into (-)-1-amino-1-deoxy-myo-inositol hydrochloride is achieved in four synthetic steps. This sequence allows the synthesis of this compound in high enantiomeric purity in a semi-preparative scale.

A concise synthetic route to the conduritols from pentoses

A short synthetic strategy for preparation of the conduritols is described. The key step employs a zinc-mediated fragmentation of protected methyl 5-deoxy-5-iodo-d-pentofuranosides followed by an allylation of the intermediate aldehyde in the same pot. The allylation is performed with 3-bromopropenyl benzoate and occurs with good diastereoselectivity. An amino group can be introduced in the product by trapping the intermediate aldehyde as the imine prior to the allylation. The functionalised 1,7-octadienes, thus obtained, are converted into protected conduritols by ring-closing olefin metathesis.