Synthesis of [(I); R = H (II) and R = a-D-gluco-pyranose (III)] was described using a block synthetic strategy. Thioglycoside (IV) was coupled to (V) yielding inositol phosphoglycan, which was selectively deprotected and reacted with 2,3,4,6-tetra-O-benzyl-a-D-glucopyranos-1-yl H-phosphonate to form the protected target mol. (VI). Deprotection of VI by acidic deacetalization/desilylation and subsequent catalytic hydrogenolysis resulted in cleavage of the anomeric phosphodiester to produce II. Debenzylation with sodium in liq. ammonia followed by acidic deacetalization/desilylation gave the target compd. III. [on SciFinder (R)]