Synthesis of 5-(substituted alkyl) picolinic acids. The dopamine beta-hydroxylase inhibitors. II.

Abstract

5-Haloalkyl or 5-branched alkyl picolinic acids, dopamine β-hydroxylase inhibitor were synthesized by the various methods. 2-Methyl-5-ethynyl pyridine (III) reacted with alkyl dihalide followed by hydrogenation to give 2-methyl-5-haloalkyl pyridine. III also reacted with ethylene oxide in the same manner to give 2-methyl-5-(4-hydroxybutyl)-pyridine, which was converted to halobutyl derivative. 2-Methylpyridine-5-aldehyde reacted with isoalkylidene phosphorane followed by hydrogenation to give 2-methyl-5-isoalkyl pyridines. These 2-methyl-5-(substituted alkyl) pyridines were oxidized via N-oxide and 2-acetoxymethyl compounds to 5-(substituted alkyl) picolinic acids.