Amino acid sulfonamides based on 4-(1-oxo-1H-isochromen-3-yl)benzenesulfonyl chloride

The creation of new amino acid derivatives of 4-(1-oxo-1H-isochromen-3-yl)benzenesulfonyl chloride 1 was investigated. The interaction of the sulfonyl chloride 1 with amino acid methyl esters (hydrochlorides) in 1,4-dioxane in the presence of triethylamine led to the corresponding amino acid sulfonamide derivatives of isocoumarin. The reaction of the sulfonyl chloride 1 with phenylalanine in the basic aqueous solution was complicated by the lactone system disclosure and led to 2'-carboxydeoxybenzoin ultimately (namely, 2-(2-(4-(N-(1-carboxy-2-phenylethyl)sulfamoyl)phenyl)-2-oxoethyl)benzoic acid). Similar product was obtained by the alkali hydrolysis of methyl ((4-(1-oxo-1H-isochromen-3-yl)phenyl)sulfonyl)leucinate.