ethyl {[(2,6-difluorophenyl)methyl](5-{4-[(3-{[(4-{5-[6-(2,6-difluorophenyl)-4-oxo-5-aza-3-oxahex-5-yl]-3-[(dimethylamino)methyl]-4-{[(6-methoxy-1,2-diazin-3-yl)amino]carbonyl}thiophen-2-yl}phenyl)amino]carbonyl}-4-oxo-3-aza-2-oxabut-4-yl)amino]phenyl}-4-[(dimethylamino)methyl]-3-{[(6-methoxy-1,2-diazin-3-yl)amino]carbonyl}thiophen-2-yl)amino}methanoate