(S)-Ethyl 6-(5-bromofuran-2-yl)-7,9-dimethyl-8,10-dioxo-11-phenyl-7,8,9,10-tetrahydro-6H-benzo[b]pyrimido[4',5':3,4]pyrrolo[1,2-d][1,4]oxazine-2-carboxylate, 98%, 250mg