All
 D03 Heterocyclic Compounds D006571 +
 D03.438 Heterocyclic Compounds, 2-Ring D006574 +
 D03.438.079 Benzazepines D001552 +
 D03.438.103 Benzimidazoles D001562 +
 D03.438.127 Benzofurans D001572 +
 D03.438.150 Benzopyrans D001578 +
 D03.438.174 Benzothiadiazines D001581 +
 D03.438.197 Benzothiepins D001582 +
 D03.438.221 Benzoxazoles D001583 +
 D03.438.245 Benzoxepins D001584 
 D03.438.449 Indazoles D007191 +
 D03.438.473 Indoles D007211 +
 D03.438.496 Indolizines D007212 
 D03.438.531 Isoquinolines D007546 +
 D03.438.612 Naphthyridines D009287 +
 D03.438.733 Pteridines D011621 +
 D03.438.759 Purines D011687 +
 D03.438.772 Pyrrolizidine Alkaloids D011763 +
 D03.438.786 Quinazolines D011799 +
 D03.438.810 Quinolines D011804 +
 D03.438.834 Quinolizines D011807 +
 D03.438.857 Quinoxalines D011810 +
 D03.438.260 Bicyclo Compounds, Heterocyclic D019086