All
 D03 Heterocyclic Compounds D006571 +
 D03.383 Heterocyclic Compounds, 1-Ring D006573 +
 D03.383.742 Pyrimidines D011743 +
 D03.383.742.698 Pyrimidinones D011744 +
 D03.383.742.698.253 Barbiturates D001463 +
 D03.383.742.698.253.077 Amobarbital D000654 
 D03.383.742.698.253.150 Barbital D001462 
 D03.383.742.698.253.317 Hexobarbital D006591 
 D03.383.742.698.253.434 Mephobarbital D008618 
 D03.383.742.698.253.488 Methohexital D008723 
 D03.383.742.698.253.500 Murexide D009114 
 D03.383.742.698.253.593 Pentobarbital D010424 
 D03.383.742.698.253.650 Phenobarbital D010634 +
 D03.383.742.698.253.762 Secobarbital D012631 
 D03.383.742.698.253.800 Thiobarbiturates D013858 +