| 540 / | HD | ORGANIC COMPOUNDS -- PART OF THE CLASS 532-570 SERIES |
| * | DD | ORGANIC COMPOUNDS (Class 532, Subclass 1) {1} |
| 1 | DF | .~ HETEROCYCLIC CARBON COMPOUNDS CONTAINING A HETERO RING HAVING CHALCOGEN (I.E., OXYGEN, SULFUR, SELENIUM OR TELLURIUM) OR NITROGEN AS THE ONLY RING HETERO ATOMS {6} |
| 121 | DF | .~.~ Azaporphyrins {1} |
| 122 | DF | .~.~.~ Phthalocyanines {8} |
| 136 | DF | .~.~.~.~ Halogen bonded directly to ring carbon of the phthalocyanine ring system {2} |
| 138 | | .~.~.~.~.~ Processes of halogenating the phthalocyanine ring system |