Disclosed herein are substituted dihydropyrazolone-pyrimidine compounds of formula (I), wherein X represents N or CH, R1 represents hydrogen or cyano, R2 represents piperazin-1-yl, where piperazin-1-yl is substituted by one substituent, where the substituent is selected from the group consisting of C3-C6-cycloalkyl； processes for their preparation, compositions comprising said compound. Said compounds are useful for treatment and/or prophylaxis of cardiovascular diseases, 5 cardiac insufficiency, anaemia, chronic kidney diseases and renal insufficiency. Particularly preferred compounds included: · 2-[6-(4-Cyclobutylpiperazin-1-yl)pyrimidin-4-yl]-4-(1H-1,2,3-triazol-1-yl)-1,2-dihydro-3H-pyrazol-3-one · 2-[6-(4-Cyclobutylpiperazin-1-yl)pyrimidin-4-yl]-4-(1H-1,2,3-triazol-1-yl)-1,2-dihydro-3H-pyrazol-3-one · 1-{ 2-[6-(4-Cyclobutylpiperazin-1-yl)pyrimidin-4-yl]-3-oxo-2,3-dihydro-1H-pyrazol-4-yl} -1H-imidazole-4-carbonitrile · 1-{ 2-[6-(4-Cyclobutylpiperazin-1-yl)pyrimidin-4-yl]-3-oxo-2,3-dihydro-1H-pyrazol-4-yl} -1H-imidazole-4-carbonitrile
