methyl (2S,3S,4S,5R,6R)-6-[(2R,3R,4S,5R,6R)-6-[(2R,3S,4S,5R,6R)-4,5-dimethoxy-6-[(2R,3R,4S,5R,6S)-6-methoxy-4,5-bis(methoxysulfonyloxy)-2-(methoxysulfonyloxymethyl)oxan-3-yl]oxy-2-methoxycarbonyloxan-3-yl]oxy-4,5-bis(methoxysulfonyloxy)-2-(methoxysulfonyloxymethyl)oxan-3-yl]oxy-3-[(2R,3R,4S,5R,6R)-3,4-dimethoxy-6-(methoxysulfonyloxymethyl)-5-[2-[2-(2-propoxyethoxy)ethoxy]ethoxy]oxan-2-yl]oxy-4,5-dimethoxyoxane-2-carboxylate