... ,16E,22Z)-(1R,4S,5'S,6S,6'R,8R,12S,13S,20R,21R,24S)-6'-[(S)-sec-butyl]-21,24-dihydroxy ... -5',11,13,22-tetramethyl-2-oxo-3,7,19-trioxatetracyclo[15.6. ... mixture with (10E,14E,16E,22Z)-(1R,4S,5'S,6S,6'R,8R,12S,13S,20R,21R,24S)-21,24 ... 22-tetramethyl-2-oxo-3,7,19-trioxatetracyclo[15.6.1.14,8.020,24]pentacosa-10,14,16 ... 12-14-32-24-55-45-40(49)29(6)19-35(46(51)58-34)48(32,45 ...