(12E,19E,21E)-24-{(2E)-4-[2-(2,3-dimethyloxiran-2-yl)-1,3-thiazol-4-yl]-1-hydroxy-1,3-dimethylbut-2-en-1-yl}-8,16,17-trihydroxy-11-(hydroxymethyl)-18-methoxy-3,6,9,15,19,23-hexamethyl-2,10-dioxooxacyclotetracosa-12,19,21-trien-3-yl 3-hydroxy-2-methylbutan