549 / | 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) {2} |
200 | DF | .~.~ Oxygen containing hetero ring (e.g., dioxirane, etc.) {16} |
263 | DF | .~.~.~ Lactones (i.e., -C(=X)O-, wherein X is chalcogen, is part of the hetero ring) {6} |
295 | DF | .~.~.~.~ The lactone ring is five-membered {10} |
326 | | .~.~.~.~.~ Preparing from compound containing -COO- group |