1,3-Dihydro-1'-acetyl-5,6'-difluorospiro(2H-benzimidazole-2,3'-(3H)indol)-2'(1'H)-one 93500-61-9 Spiro(2H-benzimidazole-2,3'-(3H)indol)-2'(1'H)-one, 1,3-dihydro-1'-acetyl-5,6'-difluoro-