2930 | | X. ORGANO-INORGANIC COMPOUNDS, HETEROCYCLIC COMPOUNDS, NUCLEIC ACIDS AND THEIR SALTS, AND SULFONAMIDES | | | | |
2932 | | Heterocyclic compounds with oxygen hetero-atom(s) only: | | | | |
2933 | | Heterocyclic compounds with nitrogen hetero-atom(s) only: | | | | |
2934 | | Nucleic acids and their salts, whether or not chemically defined; other heterocyclic compounds: | | | | |