| Popis: |
A procedure is given for the preparation and isolation of (-)-allantoin (5-ureidohydantoin). A grown culture of Pseudomonas aeruginosa was incubated with (±)-allantoin at pH 6. (+)-Allantoin was degraded by the bacteria and (-)-allantoin was removed from the medium with the aid of activated carbon. Several properties of (-)-allantoin were determined: solubility and molar rotation in various solvents, infrared spectrum, decomposition point and dependence of the molar rotation on pH. The properties were compared with those of (±)-allantoin, R- and S-hydantoin-5-acetic acid. From circular dichroism measurements of (-)-allantoin, S-hydantoin-5-acetic acid and R-carbamoylalanine it was concluded that (-)-allantoin is R-allantoin. |
