Determination of the Absolute Configuration and a Practical Chiral Synthesis of 5-[5-(1-Methylethoxy)pyridin-2-yl]-5-methyl imidazolidine-2,4-dione as a Novel Liver X Receptor β-Selective Agonist

We determined that the absolute configuration of 5-[5-(1-methylethoxy)pyridin-2-yl]-5-methylimidazolidine-2,4-dione (hydantoin) is the (S)-form for the liver X receptor (LXR) β-selective agonist through X-ray crystal structure analysis of the hydantoin hydrogen bromide salt. Furthermore, we established a practical synthesis of the chiral hydantoin with 99% ee by the optical resolution of racemic methyl 2-amino-2-[5-(1-methylethoxy)pyridin-2-yl]propanoate with d-(-)-mandelic acid on a multi-kilogram scale. Finally, we improved the synthesis method of the LXR β-selective agonist.