| 558 / | HD | ORGANIC COMPOUNDS -- PART OF THE CLASS 532-570 SERIES |
| * | DD | ORGANIC COMPOUNDS (Class 532, Subclass 1) {21} |
| 303 | DF | .~ Nitriles (i.e., compounds having cyano bonded directly to carbon, which carbon may be single bonded to any atom but may be multiple bonded only to carbon) {21} |
| 435 | DF | .~.~ Acyclic (e.g., purification of saturated nitriles, etc.) {9} |
| 436 | DF | .~.~.~ Sulfur attached indirectly to the cyano group by nonionic bonding {2} |
| 437 | | .~.~.~.~ The sulfur is double bonded to oxygen |