Phenacemide
Phenacemide, also known as phenylacetylurea, is an anticonvulsant of the ureide class. It is a congener and ring-opened analogue of phenytoin, and is structurally related to the barbiturates and to other hydantoins. Phenacemide was introduced in 1949 for the treatment of epilepsy, but was eventually withdrawn due to toxicity.