(2S)-2-[[4-[(2-amino-4-oxo-3H-pteridin-6-yl)methylamino]benzoyl]amino]-5-[[3-[[3-[2-[(2R)-2-[(4R,6S)-6-[(4R,6R)-4-(dimethylamino)-6-[[(1S,3R,4R)-3-ethyl-3,10,12-trihydroxy-4-methoxycarbonyl-6,11-dioxo-2,4-dihydro-1H-tetracen-1-yl]oxy]-2-methyloxan-3-yl]oxy-4-hydroxy-2-methyloxan-3-yl]oxy-6-methyl-3,4-dihydro-2H-pyran-5-yl]hydrazinyl]-3-oxopropyl]disulfanyl]-1-hydroperoxy-1-oxopropan-2-yl]amino]-5-oxopentanoic acid