T. Ikemoto, T. Kawamoto, K. Tomimatsu
Sep 29, 2000
Citations
0
Influential Citations
7
Citations
Journal
Tetrahedron
Abstract
Abstract A convenient synthesis of the chronic renal disease agent, trifluoro-N-[4-(3-oxo-3,5-dihydro-4H-1,4,8b-triazaacenaphthylen-4-yl)butyl]methanesulfonamide (1a), for large scale has been developed via ethyl 5-(chloromethyl)imidazo[1,2-a]pyridine-3-carboxylate (3), which was given by the regioselective chlorination of ethyl 5-methylimidazo[1,2-a]pyridine-3-carboxylate (6) with N-chlorosuccinimide (NCS) using AcOEt as a solvent in 83% yield. The condensation of 3 and primary amines gave 4,5-dihydro-3H-1,4,8b-triazaacenaphthylen-3-one derivatives (1) in good yields. The present synthesis of 1a was accomplished in five steps from 2-amino-6-methylpyridine (4) without requiring a chromatographic method.