Ledipasvir Impurity 21

Chemical Name:  Methyl ((S)-1-((1R,3S,4S)-3-(6-(7-(2-((S)-5-acetyl-5-azaspiro[2.4]heptan-6-yl)-1H-imidazol-5-yl)-9,9-difluoro-9H-fluoren-2-yl)-1H-benzo[d]imidazol-2-yl)-2-azabicyclo[2.2.1]heptan-2-yl)-3-methyl-1-oxobutan-2-yl)carbamate

Synonym: Ledipasvir Acetyl Spiro impurity