| 534 / | HD | ORGANIC COMPOUNDS -- PART OF THE CLASS 532-570 SERIES |
| * | DD | ORGANIC COMPOUNDS (CLASS 532, SUBCLASS 1) {8} |
| 573 | DF | .~ Azo {51} |
| 751 | DF | .~.~ Hetero ring containing {5} |
| 753 | DF | .~.~.~ Azo bonded directly to the hetero ring or to a polycyclo ring system which contains the hetero ring as one of the cyclos {11} |
| 756 | DF | .~.~.~.~ Two azo groups attached indirectly to each other by nonionic bonding {5} |
| 762 | | .~.~.~.~.~ Polycyclo ring system having at least three cyclos, at least one of which is a hetero ring |