合成路线1

The synthesis of delavirdine mesylate is depicted in Scheme 19654001a: The first three chemical steps are the same as those used for the synthesis of atevirdine mesylate (ATV, U-87201E) (2, 3). Nucleophilic aromatic substitution of 2-chloro-3-nitropyridine (II) with excess piperazine in acetonitrile at room temperature produces 1-(3-nitro-2-pyridyl)piperazine. Protection of the free piperazine nitrogen by treatment with di-tert-butyldicarbonate affords nitropyridine (III). Reduction of the nitro group to the amine is accomplished via hydrogenation (40 psi) over palladium on carbon. Treatment of the aminopyridine with acetone and sodium cyanoborohydride in methanol affords the 3-(1-methylethylamino)pyridine (IV). Removal of the BOC protecting group with trifluoroacetic acid and coupling of the resulting 1-[3-(1-methylethylamino)pyridyl]piperazine with 5-nitroindole-2-carboxylic acid using 1-ethyl-3-(dimethylaminopropyl)carbodiimide (EDC) or 1,1'-carbonyldiimidazole (CDI) affords (V). Catalytic reduction of the nitro group and treatment of the resulting amine with methanesulfonyl chloride provides U-90152. Dissolution of U-90152 in acetonitrile and treatment with 1 eq of methanesulfonic acid results in the precipitation of delavirdine mesylate.