Acetic acid (2R,3R,4S,5R,6S)-3-acetoxy-2-acetoxymethyl-6-[2,3-bis-(3,7,11,15-tetramethyl-hexadecyloxy)-propoxy]-5-((2R,3S,4S,5R,6R)-3,4,5-triacetoxy-6-hydroxymethyl-tetrahydro-pyran-2-yloxy)-tetrahydro-pyran-4-yl ester