XYU xyu (3S,5R,6R,7E,9R,10R,12R,14S,15E,17E,19E,21S,23S,26R,27R,30R,34aS)-5,9,27-trihydroxy-3-{(2R)-1-[(1S,3R,4R)-4-hydroxy-3-methoxycyclohexyl]propan-2-yl}-10,21-dimethoxy-6,8,12,14,20,26-hexamethyl-5,6,9,10,12,13,14,21,22,23,24,25,26,27,32,33,34,34a-octadecahydro-3H-23,27-epoxypyrido[2,1-c][1,4]oxazacyclohentriacontine-1,11,28,29(4H,31H)-tetrone XYU