| 568 / | HD | ORGANIC COMPOUNDS -- PART OF THE CLASS 532-570 SERIES |
| * | DD | ORGANIC COMPOUNDS (Class 532, Subclass 1) {4} |
| 300 | DF | .~ OXYGEN CONTAINING (E.G., PERCHLORYLBENZENE, ETC.) {11} |
| 579 | DF | .~.~ Ethers {11} |
| 671 | DF | .~.~.~ Acyclic {7} |
| 681 | | .~.~.~.~ Halogen containing {3} |
| 682 | DF | .~.~.~.~.~> Purification or recovery |
| 683 | DF | .~.~.~.~.~> Fluorine {2} |
| 686 | DF | .~.~.~.~.~> Carbon to carbon unsaturation containing |