| 556 / | HD | ORGANIC COMPOUNDS -- PART OF THE CLASS 532-570 SERIES |
| * | DD | ORGANIC COMPOUNDS (Class 532, Subclass 1) {3} |
| 170 | DF | .~ ALUMINUM CONTAINING {11} |
| 178 | | .~.~ Plural aluminums containing {2} |
| 179 | DF | .~.~.~> Chalcogen bonded directly to aluminum |
| 180 | DF | .~.~.~> Halogen bonded directly to aluminum (e.g., sesquihalides, etc.) |