The reaction of 5-acetamino-O-acetylsalicylic acid (I) with SOCl2 gives the corresponding acyl chloride (II) which is condensed with N-butylamine (III) and hydrolyzed with NaOH yielding 5-acetamino-N-butylsalicylamide (IV). The condensation of (IV) with propargyl bromide (V) by means of sodium isopropylate in refluxing isopropanol affords 2-propargyloxy-5-acetamino-N-butylbenzamide (VI) (1), which is finally hydrolyzed with hot 4N H2SO4 (2).