2-Amino-4,6-dimethoxy-5-pyrimidinol-d6 is a labeled version of 2-Amino-4,6-dimethoxy-5-pyrimidinol (A634563). 2-Amino-4,6-dimethoxy-5-pyrimidinol (A634563) is a useful intermediate and is used in the synthetic preparation of hydroxyrimsulfuron, which is a derivative of a herbicide.