546 / | 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) {1} |
1 | DF | .~.~ Hetero ring is six-membered consisting of one nitrogen and five carbons {24} |
255 | DF | .~.~.~ Plural pyridine or partially hydrogenated pyridine rings {6} |
266 | DF | .~.~.~.~ Chalcogen attached indirectly to pyridine or partially hydrogenated pyridine ring by nonionic bonding {1} |
267 |  | .~.~.~.~.~ The chalcogen, X, is in a -C(=X)- group |