Sofosbuvir metabolites Sofosbuvir IMpurity C (2R)-2-Deoxy-2-fluoro-2-Methyl-D-erythro-pentonic acid-g-lactone 3,5-bis(4-chlorobenzoate) ((2R,3R,4R)-3-(benzoyloxy)-4-fluoro-4-methyl-5-oxotetrahydrofuran-2-yl)methyl benzoate Phenol, 2,3,4,5-tetrafluoro- Phenol, 2,3,4,6-tetrafluoro- SofosBuvir Impurity 53 L-Alanine, N-[(S)-hydroxyphenoxyphosphinyl]-, 1-Methylethyl ester, (P→3'),(P'→5')-diester with (2'R)-2'-deoxy-2'-fluoro-2'-Methyluridine diisopropylphenylphosphate Sofosbuvir Impurity 104 (S)-ethyl 2-(((S)-(((2R,3R,4R,5R)-5-(2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl)-4-fluoro-3-hydroxy-4-methyltetrahydrofuran-2-yl)methoxy)(phenoxy)phosphoryl)amino)propanoate PSI 7411 Sofosbuvir IMpurity Sofosbuvir Impurity 108 D-Ribonic acid, 2-C-methyl-, γ-lactone, 3,5-dibenzoate Sofosbuvir IMpurity B PSI-7976 ((2R,3S,4S)-3-(benzoyloxy)-4-fluoro-4-Methyl-5-oxotetrahydrofuran-2-yl)Methyl benzoate