a series of novel n - alkyl - n - - 4 - alkanesulphonamidophenethylamines have been prepared , including their pharmaceutically acceptable salts and various key novel intermediates therefor . the heterocyclic moiety present in these compounds is a benzo - fused heterocyclic group derived from either benzofuran , benzothiophene , benzoxazole or quinoline , and it is attached to the adjacent methyl group of the molecule by means of the available ring carbon atom which is situated alpha to the hetero atom . these particular compounds are useful in therapy as highly effective anti - arrhythmic agents and therefore , are of value in the treatment of various cardiac arrhythmias . preferred member compounds include n - methyl - n -- 4 - methanesulphonamidophenethylamine and n - methyl - n -- 4 - methane - sulphonamidophenethylamine . methods for preparing all these compounds from known starting materials are provided .