N-[(1S)-1-[[(6S)-6-[5-[7-[2-(1R,3S,4S)-2-Azabicyclo[2.2.1]hept-3-yl-1H-benzimidazol-6-yl]-9,9-difluoro-9H-fluoren-2-yl]-1H-imidazol-2-yl]-5-azaspiro[2.4]hept-5-yl]carbonyl]-2-methylpropyl]-, methyl ester carbamic acid is an impurity of Ledipasvir (L320100), which is most commonly used in combination with sofosbuvir for treatment in chronic hepatitis C genotype 1 patients. It inhibits an important viral phosphoprotein, NS5A, which is involved in viral replication, assembly, and secretion.
