C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
C07F9/00—Compounds containing elements of Groups 5 or 15 of the Periodic Table
C07F9/02—Phosphorus compounds
C07F9/547—Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom
C07F9/553—Heterocyclic compounds, e.g. containing phosphorus as a ring hetero atom having one nitrogen atom as the only ring hetero atom