Methyl (4-Amino-2-(1-(2-fluorobenzyl)-1H-pyrazolo[3,4-b]pyridin-3-yl)-6-(methylamino)pyrimidin-5-yl)carbamate is an impurity of Riociguat (R520000); a compound used in the treatment of pulmonary hypertension. Molecular Formula: C20H19FN8O2 Molecular Weight: 422.42