Anticonvulsants. 5. Derivatives of 5-ethyl-5-phenylhydantoin and 5,5-diphenylhydantoin.

Alkoxymethyl, acyloxymethyl, and mixed alkylalkoxymethyl or alkylacyloxymethyl derivatives of 5-ethyl-5-phenylhydantoin exhibit anticonvulsant activity. Also effective are bis(alkoxymethyl) and mixed alkylalkoxymethyl derivatives of 5,5-diphenylhydantoin. Of particular interest are 1,3-bis(methoxymethyl)-5,5-diphenylhydantoin and 3-acetoxymethyl-5-ethyl-5-phenylhydantoin, which show good activity against maximal electroshock seizures, and 3-methoxymethyl-5-ethyl-5-phenylhydantoin, which is effective against both maximal electroshock and pentylenetetrazole. None of the above compounds show greater activity against maximal electroshock seizures than the parent compounds, however.