THE ALLYL GROUP FOR PROTECTION IN CARBOHYDRATE-CHEMISTRY .25. THE PREPARATION, RESOLUTION, AND PHOSPHORYLATION OF SOME BENZYL ETHERS OF MYOINOSITOL - INTERMEDIATES FOR THE SYNTHESIS OF MYOINOSITOL PHOSPHATES OF THE PHOSPHATIDYLINOSITOL CYCLE

The syntheses of the following chiral compounds are described: 1D-2,3,6-tri-, 1D-2,4,5-tri-, 1D-2,5,6-tri-, 1D-1,2,3,4-tetra-, 1D-1,2,3,6-tetra-, 1D-1,2,4,5-tetra-, and 1D-2,3,5,6-tetra-O-benzyl-myo-inositol; and 1D-2,5,6-tri-O-benzyl-1-O-p-methoxybenzyl-and 1D-2,3,5,6-tetra-O-benzyl-1-O-p-methoxybenzyl-myo-inositol. The absolute configurations were established by reference to 1D-5,6-di-O-methyl-myo-inositol prepared from known 1D-1,2,4-tri-O-benzyl-5,6-O-isopropylidene-myo-inositol. The preparation of the mesoderivative 2,4,5,6-tetra-O-benzyl-myo-inositol is also described. Several of the benzyl ethers were converted into protected phosphate esters by phosphitylation with bis(benzyloxy)diisopropylaminophosphine or bis(2-cyanoethoxy)diisopropylaminophosphine and subsequent oxidation with m-chloroperoxybenzoic acid. On treatment with sodium iodide in acetone, the syrupy octabenzyl esters of 2,5-di-O-benzyl-myo-inositol 1,3,4,6-tetrakisphosphate and 1D-2,6-di-O-benzyl-myo-inositol 1,3,4,5-tetrakisphosphate were converted into the crystalline tetrasodium salts of the corresponding tetrakis(benzyl phosphates). These salts are useful compounds for hydrogenolysis to give myo-inositol tetrakisphosphates of the phosphatidylinositol cycle since phosphate migration would not be expected to occur. 1D-3,6-di-O-octyl-myo-inositol and its racemate were prepared and each showed liquid crystalline behaviour on heating.