AN AM1 STUDY OF ALLANTOIN

The ground state geometry of allantoin has been studied using the AM1 method and electronic transitions calculated using the CNDO/s-CI method. The calculation predicts that three different conformations can occur in solutions; the most stable conformation is in agreement with that observed by crystallography. The molecule is shown to absorb in the vacuum UV region. The occurrence of allantoin in human tissues in the presence of calcium ions is known to cause Reye's syndrome. The most favourable site of binding of calcium ions with allantoin has been found using electrostatic potential mapping.