The synthesis of p‐guanidino‐salicylic acid and some related compounds

Abstract
The syntheses of 4‐guanidino‐salicylic acid, 4‐(N′‐cyanoguanidino)‐ salicylic acid, and some related compounds are described.Intermolecular coupling of the diazonium salt of ρ‐amino‐salicylic acid and of its methyl ester yielded products which are in all probability 2,4,3′‐trihydroxy‐5,4′‐dicarboxy‐azobenzene and the methyl ester thereof.These and some related compounds were prepared in order to examine their possible growth‐inhibiting properties for Mycobact. tuberculosis.