BaccatinIV

(2aR)-2a,3,4,4a,5,6,9,10,12,12aβ-Decahydro-4aα,8,13,13-tetramethyl-7,11β-methano-1H-cyclodeca[3,4]benz[1,2-b]oxete-4α,5β,6α,9β,11α,12β,12bβ-heptol 4,5,6,9,12,12b-hexaacetate