New syntheses of n,n-(diethylaminoethyl)- - 4 amino 5 chloro 2 methoxybenzamide

摘要

Preparation of (I) by methylation of p-aminosalicylic acid under anhydrous conditions give 4-amino-2-methoxymethylbenzoate (II). Reaction with PhICl2 gives 4-amino-5-chloro-2-methoxymethylbenzoate which is converted to (I) by reaction with N,N-diethylethylenediamine (III). Alternative procedures are: a) Reaction of (II) with amine (III) to give N,N-(diethylethylen-diamine)-4-amino-2-methoxybenzamide (IV) followed by chlorination with PHICl2 to (I). b) Base hydrolysis of (II) to 4-amino-2-methoxybenzoic acid (V), which with amine (III) and PCl3 gives (IV), and chlorination with PHCl2 to (I). c) Reaction of (V) with PHICl2 followed by condensation with amine (III) and PCl3 to give (I). (I) is used in treatment of digestive system disorders.