丙酮 、
(4S,7R,8S,9S,13R,14S,16S)-4,8,13,14-Tetrahydroxy-5,5,7,9-tetramethyl-16-[(E)-1-methyl-2-(2-methyl-thiazol-4-yl)-vinyl]-oxacyclohexadecane-2,6-dione 在
对甲苯磺酸 作用下,
以43%的产率得到(3aS,5S,9S,12R,13S,14S,17aR)-9,13-Dihydroxy-2,2,10,10,12,14-hexamethyl-5-[(E)-1-methyl-2-(2-methyl-thiazol-4-yl)-vinyl]-dodecahydro-1,3,6-trioxa-cyclopentacyclohexadecene-7,11-dione