An Efficient Syntesis of 1,8-Naphthyridin-2(1<i>H</i>)-ones: Synthesis of Leukotriene Inhibitor SCH 37224

Abstract

A new, efficient synthesis of 1,8-naphthyridin-2(1H)-ones as applied to the synthesis of the leukotriene release inhibitor, 1,2-dihydro-1-phenyl-3-pyrrolidinio-2-oxo-1, 8-naphthyridin-4-olate inner salt (4) from methyl 2-phenylamino-3-pyridinecarboxylate, (1a), has been described. Towards this synthesis a new reaction procedure for the N-chloroacylation of 1a was developed. The high yield for the rest of the synthesis was obtained by establishing reaction conditions that utilized the solubility, and the stability properties 4.