| 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} |
| 243 | DF | .~.~.~ Oxygen bonded directly at alpha position (i.e., 1-, 4-, 5- or 8-position) {4} |
| 246 |  | .~.~.~.~ Oxygen bonded directly to the nitrogen (e.g., nitro bonded directly at 8 position, etc.) |