[1,1′-Biphenyl]-3-carboxylic acid, 2′-hydroxy-3′-nitro;[1,1′-Biphenyl]-3-carboxylic acid, 2′-hydroxy-3′-nitro; 3′-Nitro-2′-hydroxybiphenyl-3-carboxylic Acid; Eltrombopag Impurity 22 ;