{2-[5-Bromo-3-(2-fluoro-6-trifluoromethyl-benzyl)-4-methyl-2,6-dioxo-3,6-dihydro-2H-pyrimidin-1-yl]-1-phenyl-ethyl}-carbamic Acid tert-Butyl Ester is an intermediate used in the synthesis of Elagolix Methoxy-d3 Sodium Salt (E501024), which is the labeled analogue of Elagolix (E50108), a novel uracil phenylethylamine that acts as potent human gonadotropin-releasing hormone receptor (hGnRH-R) antagonist.