| 987 / | HD | ORGANIC COMPOUNDS CONTAINING A Bi, Sb, As, OR P ATOM OR CONTAINING A METAL ATOM OF THE 6TH TO 8TH GROUP OF THE PERIODIC SYSTEM |
| 30 | DF | PHOSPHORUS COMPOUNDS (9/02; 9/06) {15} |
| 49 | DF | .~ Ring is devoid of a P or a metal atom and contains at least one hereto atom (O, S, N, Se, or Te) and may or may not contain C (9/547; 9/6524) {9} |
| 67 | DF | .~.~ Exactly three N atoms as only hetero atoms in ring (9/6515) {2} |
| 68 | | .~.~.~ Six-membered ring containing three N and three C atoms (9/6521; 9/6521E; 9/6521G; 9/6521R) {2} |
| 69 | DF | .~.~.~.~> Six-membered ring is condensed or bridged to a carbocyclic ring system (9/6521V) |
| 70 | DF | .~.~.~.~> C atom of ring is bonded directly to a P atom, or is bonded directly to a hetero atom other than N and the hetero atom is directly bonded to a P atom (9/6521K) |