534 / | HD | ORGANIC COMPOUNDS -- PART OF THE CLASS 532-570 SERIES |
* | DD | ORGANIC COMPOUNDS (CLASS 532, SUBCLASS 1) {8} |
573 | DF | .~ Azo {51} |
583 | .~.~ Formation of azo group by coupling diazonium compound with coupling component in presence of ammonia, a Group IIA light metal hydroxide or a Group IA or IIA light metal phosphate |