The synthesis of substituted (4S)-4-(hydroxymethyl)imidazolidin-2-ones as novel protein kinase C modulators

The total synthesis of substituted (4S)-4-(hydroxymethyl)imidazolidin-2-ones from D-serine methyl ester is described. The key step in the synthesis is a reductive amination reaction which is brought about using titanium(IV) isopropoxide and sodium cyanoborohydride, followed by the cyclization to urea using triphosgene after deprotection.