| 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} |
| 90 | DF | .~.~ Single N as only hetero atom in ring (9/553; 9/568) {6} |
| 103 | | .~.~.~ Five-membered ring containing a single N atom (9/572; 9/572G; 9/572K; 9/572K2; 9/572K4; 9/572R) {2} |
| 104 | DF | .~.~.~.~> Ring is condensed or bridged to a carbocyclic ring system (9/572V) |
| 105 | DF | .~.~.~.~> N atom of ring is bonded directly to a P atom or indirectly to a P atom other than through a ring atom of the five-membered ring (9/572E) |