(6R, [7R,] [12S,] 13S, [14S,] [19R,] [20R,] [21R,] 22S)-21-(TERT-BUTYLDIMETHYLSILANYLOXY)- 7,13, [19-TRIS- (4-METHOXYBENZYLOXY)-6,] 12,14, 20,22-pentamethylhexacosa-2, 4,10, 15,23, 25- hexaenoic acid methyl ester