Nirvanol
Nirvanol, also known as ethylphenylhydantoin, is a derivative of hydantoin with anticonvulsant properties. Its 5-ethyl-5-phenyl substitution pattern is similar to that of phenobarbital. It is useful in the treatment of chorea.Metabolism of nirvanol is stereoselective, with the - enantiomer undergoing roughly 14 times more hydroxylation at the 4 position of the phenyl group than the -enantiomer.