NEW X-RAY-CONTRAST MATERIALS AND PROCESS FOR PRODUCING THEIR ACTIVE AGENTS, I.E. NEW DICARBOXYLIC-BIS-SQUARE BRACKET-3,5-BIS-BRACKET-CARBAMOYL-BRACKET CLOSED-2,4,6-TRIIODO-ANILIDES-SQUARE BRACKET CLOSED

摘要

Dicarboxylic acid bis(3,5-dicarbamoyl-2,4,6-triiodoanilides) of the formula wherein R1 is lower straight-chain or branched-chain mono- or polyhydroxyalkyl; R2 is hydrogen, lower alkyl or R1; R3 is hydrogen or lower alkyl; and X is a direct bond or straight-chain or branched-chain alkylene interrupted by one or more oxygen or substituted by hydroxy or lower alkyl, are useful in x-ray contrast media.