The present invention is concerned with deuterium-enriched pyrimidine compounds of formula I, their derivatives and pharmaceutically acceptable salts and methods of use thereoffor the treatment of pulmonary arterial hypertension, pulmonary hypertension associated with chronic obstructive pulmonary disease (COPD), asthma, cystic fibrosis, hypertension, ischemic stroke, angina pectoris, congestive heart failure, arrhythmia, arterial fibrillation, Alzheimer's disease, cognition impairment, memory decline, and schizophrenia, and depression.
