X-RAY CONTRAST MEDIUM ⅡSYNTHESIS OF 3-ACETYLAMINO-2,4,6-TRIIODOBENZOIC ACID

A detailed procedure,which is essentially a modification of Wallingford's method,is described here for the Synthesis of 3-acetylamino-2,4,6,-triiodoben- zoic acid (Urokon). For the reduction of m-nitrobenzoic acid,five different reducing agents were employed and compared.The yield was highest when tin and hydrochloric acid were used. Wallingford's method for the iodination of m-aminobenzoic acid was found to be satisfactory.However,we carried out the subsequent acetylation in the cold and obtained a purer product then that obtainable by the Wallingford's original procedure. The Urokon Synthesized exhibits low toxicity;when the drug was admini- stered intravenously to white mice,the LD₅₀ was found to be 5640 mg/kg.