Benzoic acid (2S,3S,4S,5S,6S)-4,5-bis-benzyloxy-6-[(R)-1-benzyloxy-2-(dimethyl-phenyl-silanyl)-ethyl]-2-[(2R,3R,4S,5S,6S)-3,5-bis-benzyloxy-2-((R)-1,2-bis-benzyloxy-ethyl)-6-methoxy-tetrahydro-pyran-4-yloxy]-tetrahydro-pyran-3-yl ester