Compounds that include a non-fused imidazole ring. Hydantoin and its derivatives (eg nitro, methyl and phenylhydantoin). Leiden

Compounds containing an imidazole (if hydrogenated)
This section includes:
1 - Hydantoin and its derivatives (such as nitrohydantoin, methylantantoin and phenylhydantoin) and obtained by intensification of glycolic acid with urea.
2- Leiden:
White crystals absorb moisture, used in medicine as a solvent for uric acid.