The reaction of 3-amino-4-benzyloxyacetophenone (I) with phosgene in toluene gives 3-isocyanate-4-benzyloxyacetophenone (II), which by reaction with ammonia in benzene yields 4-benzyloxy-3-ureidoacetophenone (III). The bromination of this product with Br2 in CHCl3 affords 4-benzyloxy-3-ureidophenacyl bromide (IV), amorphous product that is condensed with N-benzyl-N-tert-butylamine (V) in acetonitrile giving 4-benzyloxy-3-ureido-alpha-(N-benzyl-N-tert-butylamine)acetophenone hydrochloride (VI), m.p. 220-1 C. This product is finally hydrogenated with H2 over Pd/C in methanol