| 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} |
| 300.1 | DF | .~.~.~ 1,3-diazoles (including hydrogenated) {9} |
| 300.7 | DF | .~.~.~.~ Spiro {2} |
| 301.1 |  | .~.~.~.~.~ One of the two rings which form the spiro is part of a polycyclo ring system |