合成路线1

The reaction of 1,6-anhydro-beta-D-glucopyranose (I) with tosyl chloride in pyridine gives 1,6-anhydro-2,4-di-O-(p-toluenesulfonyl)-beta-D-glucopyranose (II), which is oxidized with NaBrO3 and RuCl3 in acetonitrile/water yielding 1,6-anhydro-2,4-di-O-(p-toluenesulfonyl)-beta-D-glucopyranos-3-ulose (III). Finally, the deoxygenation of the ditosylate (III) to the desired intermediate (IV) is performed with Zn dust and NH4OAc in THF. The 1,6-anhydro-2,4-di-O-(p-toluenesulfonyl)-beta-D-glucopyranose (II) obtained before can be reduced with Super-hydride in THF yielding the bicyclooctanol (V), which is finally oxidized to the target ketone (IV) by means of pyridinium chlorochromate (PCC) in dichloromethane. The treatment of D-glucose (VI) successively with TsCl and pyridine, with DBU and finally again with TsCl gives the previously reported 1,6-anhydro-2,4-di-O-(p-toluenesulfonyl)-beta-D-glucopyranose (II), which is reduced to the previously reported bicyclooctanol (V) with LiEt3BH. Finally, this compound is oxidized with PCC as before to the target ketone (IV).