Synthesis, analysis and toxicity of some compounds which may be formed during the synthesis of iopentol.

The process developed for the synthesis of iopentol consists of several steps. Nine possible impurities from the synthesis of iopentol have been synthesized and one has been isolated from iopentol mother liquor. These substances have been analysed by HPLC methods developed for routine control of iopentol bulk substance. Capacity factors have been calculated for each compound which relate its position in the chromatogram to iopentol. Some of the synthesized compounds have never been found in iopentol and their toxicities have therefore not been determined. Approximate intravenous LD50 values in mice have been determined for the remaining compounds. Taking into consideration these results and the small quantities in which the impurities are present, it is unlikely that they will affect the safety of the final product.