A Novel Scalable Synthesis of Pramipexole

作者：Zivec Matej; Anzic Borut; Gobec Stanislav^*

来源：Organic Process Research & Development, 2010, 14(5): 1125-1129.

DOI：10.1021/op1000989

Pramipexole is a dopamine D(2) subfamily receptor agonist that is used for the treatment of Parkinson's disease. We report here on the successful application of the Fukuyama alkylation protocol to the development of a novel and scalable process for synthesis of pramipexole and its pharmaceutically acceptable salts. The synthesis consists of converting the crucial intermediate (S)-2,6-diamino-4,5,6,7-tetrahydrobenzothiazole to (6S)-N-(2-amino-4,5,6,7-tetrahydrobenzothiazole-6-y1)-2-nitrobenzenesulfonamide, which is in turn monoalkylated to (6S)-N-(2-amino-4,5,6,7-tetrahydrobenzothiazole-6-y1)-2-nitro-N-propylbenzenesulfonamide. Deprotection of the latter yields pramipexole base, which is finally converted to a crude pramipexole dihydrochloride monohydrate with a yield of over 50% over four steps. The process allows for the telescoping of the final three steps, has high conversion rates of intermediates, offers ease of purification, and preserves high optical purity throughout all of the stages.

• 出版日期2010-10