14446-69-6Relevant academic research and scientific papers
Synthesis of a naphthyridone p38 MAP kinase inhibitor
Chung, John Y. L.,Cvetovich, Raymond J.,McLaughlin, Mark,Amato, Joseph,Tsay, Fuh-Rong,Jensen, Mark,Weissman, Steve,Zewge, Daniel
, p. 8602 - 8609 (2007/10/03)
Compound 1 is a p38 MAP kinase inhibitor potentially useful for the treatment of rheumatoid arthritis and psoriasis. A novel six-step synthesis suitable for large-scale preparation was developed in support of a drug development program at Merck Research Laboratories. The key steps include a tandem Heck-lactamization, N-oxidation, and a highly chemoselective Grignard addition of 4-(N-tert-butylpiperidinyl)-magnesium chloride to a naphthyridone N-oxide. The N-oxide exerted complete chemoselectivity via chelation in directing the Grignard addition to the α position as opposed to 1,4-addition on the enelactam. The dihydropyridyl adduct was in situ aromatized with isobutylchloroformate followed by heating in pyridine. Syntheses of Grignard precursor, N-tert-butyl-4-chloro-piperidine, were accomplished via transamination with a quaternary ammonium piperidone or via addition of methylmagnesium chloride to an iminium ion. Utilizing this chemistry, multi-kilogram preparation of compound 1 was successfully demonstrated. American Chemical Society.
