[(4S,5'S,6R,6'S,8R,10E,13S,14E,16E,20R,21R,24S)-6'-[(E)-but-2-en-2-yl]-21,24-dihydroxy-5',11,13,22-tetramethyl-2-oxospiro[3,7,19-trioxatetracyclo[15.6.1.14,8.020,24]pentacosa-10,14,16,22-tetraene-6,2'-oxane]-12-yl] 2-methylpropanoate
[(4s,5's,6r,6's,8r,10e,13s,14e,16e,20r,21r,24s)-6'-[(e)-but-2-en-2-yl]-21,24-dihydroxy-5',11,13,22-tetramethyl-2-oxospiro[3,7,19-trioxatetracyclo[15.6.1.14,8.020,24]pentacosa-10,14,16,22-tetraene-6,2'-oxane]-12-yl] 2-methylpropanoate