Barbiturates are prepared by treating diethyl malonate or a derivative of diethyl malona...

Barbiturates are prepared by treating diethyl malonate or a derivative of diethyl malonate with urea in the presence of sodium ethoxide as a catalyst. Following is an equation for the preparation of barbital from a substituted diethyl malonate and urea. Barbital, a long-duration hypnotic and sedative, is prescribed under a dozen or more names. Draw the structural formula of barbital.