B-Urea, also known as Hydantoin, is a scientific name for imidazole -2,4-Two ketone, is a five-yuan nitrogen-saturated heterocyclic compounds. It can be regarded as a product of two times condensation of one molecule of ethanol acid and one molecule urea. is the derivative of imidazole, belongs to the double Caprolactam and amide class. Is the core structure of some drugs.