Coupling of 2-benzyloxyaniline (I) with N-Boc-glycine (II) by means of EDC aforded amide (III). Subsequent N-alkylation of (III) with N-methyl-N-phenyl-2-bromoacetamide (IV) in the presence of NaH provided diamide (V). Hydrogenolysis of the benzyl ether of (V) over Pd/C gave phenol derivative (VI) (1). Phenol (VI) was then alkylated with bromoamide (IV) to furnish ether (VII). After cleavage of the Boc group of (VII) with trifluoroacetic acid, the resulting amine (VIII) was reacted with carbonyldiimidazole to produce imidazolide (IX), which was subsequently coupled with aniline (X) yielding urea (XI). Finally, basic hydrolysis of the methyl ester group of (XI) gave the title carboxylic acid.

Coupling of 2-benzyloxyaniline (I) with N-Boc-glycine (II) by means of EDC aforded amide (III). Subsequent N-alkylation of (III) with N-methyl-N-phenyl-2-bromoacetamide (IV) in the presence of NaH provided diamide (V). Hydrogenolysis of the benzyl ether of (V) over Pd/C gave phenol derivative (VI) (1). Phenol (VI) was then alkylated with bromoamide (IV) to furnish ether (VII). After cleavage of the Boc group of (VII) with trifluoroacetic acid, the resulting amine (VIII) was reacted with carbonyldiimidazole to produce imidazolide (IX), which was subsequently coupled with aniline (X) yielding urea (XI). Finally, basic hydrolysis of the methyl ester group of (XI) gave the title carboxylic acid.