Five-membered Ring Containing Three N And Two C Atoms (9/6518; 9/6518g; 9/6518r) Patents (Class 987/71)
Five-membered ring is condensed or bridged to a carbocyclic ring system (9/6518v) (Class 987/72)
C atom of ring is bonded directly to a p atom or is bonded directly to a hetero atom other than n and which hetero atom is directly bonded to a p atom (9/6518k) (Class 987/73)
N atom of ring is bonded directly to a p atom or is bonded indirectly to a p atom other than through a ring atom of the five-membered ring (9/6518e) (Class 987/74)

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