2-[(1R,4S,8R,10S,13S,16S,34S)-34-butan-2-yl-13-[(2R,3R)-3,4-dihydroxybutan-2-yl]-8,22-dihydroxy-2,5,11,14,27,30,33,36,39-nonaoxo-27lambda4-thia-3,6,12,15,25,29,32,35,38-nonazapentacyclo[14.12.11.06,10.018,26.019,24]nonatriaconta-18(26),19(24),20,22-tetraen-4-yl]acetamide
A cyclic octapeptide with a thioether bridge between the cystine and tryptophan. It inhibits RNA POLYMERASE II. Poisoning may require LIVER TRANSPLANTATION.