合成路线1

The reaction of N-(tert-butoxycarbonyl)-D-alanine (I) with 3,5-dichloroaniline (II) by means of isobutyl chloroformate and NMM gives the corresponding protected amide (III), which is deprotected with TFA to yield alaninamide (IV). The cyclization of (IV) with pivalaldehyde (V) in hot toluene affords the imidazolidinone (VI), which is acylated with TFAA and TEA in THF to provide the trifluoroacetyl derivative (VII). The alkylation of (VII) with 4-bromobenzyl bromide (VIII) and LHMDS in THF gives the benzyl derivative (IX), which is treated first with benzyl trimethylammonium chloride and NaOH and then with 6N HCl (or t-BuOK in THF/water) to yield the propionamide derivative (X). The cyclization of (X) with methyl chloroformate and TEA in THF affords the imidazolidinedione (XI), which is finally methylated with methyl iodide and LHMDS to provide the target compound.