(2R,3S,4aR,5aS,7aR,8aS,10R,11S,12aR,13aS,14aR,15R,16aS)-10-(benzyloxy)-11-(2-(benzyloxy)ethyl)-3,7a,8a,11,15-pentamethyl-2-(((2S,3S)-3-vinyloxiran-2-yl)methyl)octadecahydro-2H-pyrano[2',3':5,6]pyrano[3,2-b]pyrano[2',3':6,7]oxepino[2,3-f]oxepin-3-ol