Vibegron Impurity 27

2H-Pyrrole, 3,4-dihydro-5-[(4-nitrophenyl)methyl]-2-[(R)-phenyl[(trimethylsilyl)oxy]methyl]-, (2R); 
(2R)-3,4-Dihydro-5-[(4-nitrophenyl)methyl]-2-[(R)-phenyl[(trimethylsilyl)oxy]methyl]-2H-pyrrole;