合成路线图解说明: The cyclization of 3,4-diaminobenzoic acid (I) with 4-nitrobenzaldehyde (II) in nitrobenzene at 160 C gives 2-(4-nitrophenyl)-1H-benzimidazole-5-carboxylic acid (III), which is condensed with 2-aminopyridine (IV) by means of CDI in DMF to yield the corresponding amide (V). The reduction of the nitro group of (V) with H2 over Pd/C in methanol affords 2-(4-aminophenyl)-N-(2-pyridinyl)-1H-benzimidazole-5-carboxamide (VI). Finally, this compound is condensed with adamantane-1-carboxylic acid (VII) to provide the target diamide. |