| 548 / | HD | ORGANIC COMPOUNDS -- PART OF THE CLASS 532-570 SERIES | 
| 
 | 
| * | DD | ORGANIC COMPOUNDS (Class 532, Subclass 1) {1} | 
| * | DD | .~ HETEROCYCLIC CARBON COMPOUNDS CONTAINING A HETERO RING HAVING CHALCOGEN (I.E., OXYGEN, SULFUR, SELENIUM, OR TELLURIUM) OR NITROGEN AS THE ONLY RING HETERO ATOMS (Class 540, subclass 1) {4} | 
| 100 | DF | .~.~ Hetero ring is five-membered having two or more ring hetero atoms of which at least one is nitrogen (e.g., selenazoles, etc.) {18} | 
| 262.2 | DF | .~.~.~ 1,2,4-triazoles (including hydrogenated) {13} | 
| 264.8 |  | .~.~.~.~ Nitrogen attached directly to the triazole ring by nonionic bonding {3} | 
| 265.2 | DF | .~.~.~.~.~> Plural nitrogens attached directly to the triazole ring by nonionic bonding | 
| 265.4 | DF | .~.~.~.~.~> Having -C(=X)-, wherein X is chalcogen, bonded directly to the nitrogen | 
| 265.6 | DF | .~.~.~.~.~> The nitrogen is further bonded to hydrogen only |