Isonipecotic acid (I) was protected with benzyl chloroformate and the resultant 1-(benzyloxycarbonyl)piperidine-4-carboxylic acid (II) was subsequently converted to the corresponding acid chloride (III) by treatment with SOCl2. Coupling of acid chloride (III) with 4-(tert-butoxycarbonylamino)piperidine (IV) afforded the piperidinyl amide (V), which was further reduced with BH3 to the piperidinylmethyl piperidine (VI). Aminopiperidine (VII), obtained by acidic cleavage of the N-Boc group of (VI), was then coupled with 4-amino-5-chloro-2-methoxybenzoic acid (VIII) to provide amide (IX). Deprotection of the N-benzyloxycarbonyl group was carried out by means of methanesulfonic acid in the presence of anisole to give (X). Acylation of piperidine (X) with the protected aminoacid (XI) yielded amide (XII). Then, selective reduction of the aliphatic amide function, followed by deprotection of the amino group provided the title compound.

Isonipecotic acid (I) was protected with benzyl chloroformate and the resultant 1-(benzyloxycarbonyl)piperidine-4-carboxylic acid (II) was subsequently converted to the corresponding acid chloride (III) by treatment with SOCl2. Coupling of acid chloride (III) with 4-(tert-butoxycarbonylamino)piperidine (IV) afforded the piperidinyl amide (V), which was further reduced with BH3 to the piperidinylmethyl piperidine (VI). Aminopiperidine (VII), obtained by acidic cleavage of the N-Boc group of (VI), was then coupled with 4-amino-5-chloro-2-methoxybenzoic acid (VIII) to provide amide (IX). Deprotection of the N-benzyloxycarbonyl group was carried out by means of methanesulfonic acid in the presence of anisole to give (X). Acylation of piperidine (X) with the protected aminoacid (XI) yielded amide (XII). Then, selective reduction of the aliphatic amide function, followed by deprotection of the amino group provided the title compound.