| 552 / | HD | ORGANIC COMPOUNDS -- PART OF THE CLASS 532-570 SERIES |
|
| * | DD | ORGANIC COMPOUNDS (Class 532, subclass 1) {11} |
| 208 | DF | .~ Polycyclo ring system containing anthracene configured ring system having at least one double bond between ring members and having oxygen single bonded or any atom double bonded directly at the 9- and 10-positions (e.g., anthraquinones, etc.) {19} |
| 238 | DF | .~.~ Nitrogen bonded directly at alpha position (i.e., 1-, 4-, 5- or 8-position) {7} |
| 240 | DF | .~.~.~ Oxygen bonded directly at beta position (i.e., 2-, 3-, 6- or 7-position) {1} |
| 241 |  | .~.~.~.~ Additional carbon bonded directly to the oxygen {1} |
| 242 | DF | .~.~.~.~.~> The additional carbon is part of a ring |