A Concise Synthesis and the Antibacterial Activity of 5,6-Dimethoxynaphthalene-2-carboxylic Acid

摘要

5,6-Dimethoxynaphthalene-2-carboxylic acid was synthesized in 7 steps and with an overall yield of 46%.Bromination of 2-naphthol,and methylation with dimethyl sulfate followed by Priedel-Crafts acyla-tion with AcCl gave 2-acetyl-5-bromo-6-methoxynaphthalene.2-Acetyl-5-bromo-6-methoxynaphthalene was converted to 5-bromo-6-methoxynaphthalene-2-carboxylic acid by a haloform reaction.The ester-ification of the acid with methanol,methoxylation with NaOCH_3 in the presence of Cul and subsequent de-esterification with NaOH afforded 5,6-dimethoxynaphthalene-2-carboxylic acid.The 5-bromo-6-methoxynaphthalene-2-carboxylic acid and 5,6-dimethoxynaphthalene-2-carboxylic acid were found to have in vitro antibacterial activity against some pathogenic bacteria.