with only hydrogen atoms or radicals containing only hydrogen and carbon atoms, directly attached to ring nitrogen atoms

Full Title

Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings > having one double bond between ring members or between a ring member and a non-ring member > with only hydrogen atoms or radicals containing only hydrogen and carbon atoms, directly attached to ring carbon atoms > with alkyl radicals, containing more than four carbon atoms, directly attached to ring carbon atoms > with only hydrogen atoms or radicals containing only hydrogen and carbon atoms, directly attached to ring nitrogen atoms