Methyl 5-hydroxy-3-iodobenzoate (I) was protected as the benzyl ether (II). Subsequent coupling of (II) with rolipram (III) in the presence of K2CO3 and copper catalyst afforded the N-aryl derivative (IV), which was debenzylated by hydrogenation over Pd/C. The resulting phenol (V) was alkylated with 3-methoxybenzyl chloride (VI) to provide ether (VII). Further basic hydrolysis of the methyl ester of (VII) yielded the corresponding carboxylic acid (VIII). This was finally coupled with N,N-dimethylhydrazine by means of EDC and HOBt to furnish the target hydrazide.

Methyl 5-hydroxy-3-iodobenzoate (I) was protected as the benzyl ether (II). Subsequent coupling of (II) with rolipram (III) in the presence of K2CO3 and copper catalyst afforded the N-aryl derivative (IV), which was debenzylated by hydrogenation over Pd/C. The resulting phenol (V) was alkylated with 3-methoxybenzyl chloride (VI) to provide ether (VII). Finally, basic hydrolysis of the methyl ester of (VII) furnished the corresponding carboxylic acid.