[The reaction of cyclohexylsulphamic acid (Cyclamate) with nitrous acid in aqueous HCl-solution, isolated human gastric juice and urine (author's transl)].

The pH dependence of the formation and decomposition of the N-nitroso derivative, which is produced by the reaction of cyclohexylsulphamic acid with nitrous acid, was investigated by means of continuous photometric measurement of the changes in absorbance. Reaction at pH 2.45 resulted in an optimal yield of the N-nitroso derivative. The half-life of the decomposition reaction (the reactants cyclohexylsulphamic acid/sodium nitrite being in a molar ratio of 1:1.11) at pH 2.61 was 13.6 min. The N-nitroso derivative showed a relatively high stability at pH 4.5. The reaction in isolated human gastric juice and urine showed the same pH dependency as in aqueous HCl solution.