Reduced quinolines and quinolinium compounds—I : Reduction of quinoline analogs of model compounds for coenzyme

Abstract

The reduction of quinoline analogs of model compounds for coenzyme I was investigated. The reaction of 1-benzyl-3-carbamidoquinolinium chloride (I) with alkaline sodium dithionite yielded predominantly a stable product which was shown to be sodium 1-benzyl-1,4-dihydro-3-carbamido-4-quinoline sulfonate (II). Compound II was also obtained from the reaction of I with alkaline sodium bisulfite. The reaction of II with sodium dithionite yielded 1-benzyl-1,4-dihydro-3-carbamidoquinoline (III). When II was treated with a variety of acids, a new compound (V) was obtained and identified as 1-benzyl-3-carbamidoquinolinium 1-benzyl-1,4-dihydro-3-carbamidoquinoline-4-sulfonate. This compound was also obtained from the reaction of I with aqueous sulfur dioxide or thionyl chloride and pyridine or aqueous sodium bisulfite. 1-Methyl-3-carbamidoquinolinium iodide (VI) was reduced by alkaline sodium dithionite to yield 1-methyl-1,4-dihydro-3-carbamidoquinoline (VII). Compound VII reduced hexachloroacetone to hexachloroisopropanol in 10% yield.