5157: Other heterocyclic compounds; nucleic acids

51571: Heterocyclic compounds, nitrogen hetero-atom, pyraz. 51572: Hydantoine and its derivatives 51573: Other heterocycl. compounds, unfused imidazole ring 51574: Heterocyc. comp., nitrogen hetero-atom, pyridine ri. 51575: Heteroc. comp., nitrogen hetero-atom, quino. or iso. 51576: Heteroc. comp., nitrogen hetero-atom, pyrim. or pip. 51577: Other heterocyclic comp. with nitrogen hetero-atom 51578: Heterocyclic compounds, phenothiazine ring-system 51579: Heterocyclic compounds, n.e.s. 5157: Other heterocyclic compounds; nucleic acids