267877-05-4
20-benzyl-8-sec-butyl-17-(tert-butyl-dimethyl-silanyloxymethyl)-14-[1-(1,1-dimethyl-allyloxy)-ethyl]-11-(1,1-dimethyl-allyloxymethyl)-5-methyl-hexadecahydro-3a,6,9,12,15,18,21-heptaaza-cyclopentacycloheneicosene-4,7,10,13,16,19,22-heptaone