| 546 / | HD | ORGANIC COMPOUNDS -- PART OF THE CLASS 532-570 SERIES | 
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| * | DD | ORGANIC COMPOUNDS (Class 532, Subclass 1) {1} | 
| * | DD | .~ HETEROCYCLIC CARBON COMPOUNDS CONTAINING A HETERO RING HAVING CHALCOGEN (I.E., OXYGEN, SULFUR, SELENIUM, OR TELLURIUM) OR NITROGEN AS THE ONLY RING HETERO ATOMS (Class 540, subclass 1) {1} | 
| 1 | DF | .~.~ Hetero ring is six-membered consisting of one nitrogen and five carbons {24} | 
| 184 | DF | .~.~.~ Piperidines {8} | 
| 192 | DF | .~.~.~.~ Additional ring containing {9} | 
| 195 | DF | .~.~.~.~.~ The additional ring is one of the cyclos in a polycyclo ring system {3} | 
| 196 | DF | .~.~.~.~.~.~ Hetero ring in the polycyclo ring system {3} | 
| 202 |  | .~.~.~.~.~.~.~ Ring sulfur in the polycyclo ring system |