0 2933.39 Heterocyclic compounds with nitrogen hetero-atom[s] only, containing an unfused pyridine ring, whether or not hydrogenated, in the structure (excl. pyridine, piperidine, alfentanil ‘inn’, anileridine ‘inn’, bezitramide ‘inn’, bromazepam ‘inn’, difenoxin ‘inn’, diphenoxylate ‘inn’, dipipanone ‘inn’, fentanyl ‘inn’, ketobemidone ‘inn’, methylphenidate ‘inn’, pentazocine ‘inn’, pethidine ‘inn’, pethidine ‘inn’ intermediate a, phencyclidine ‘inn’‘pcp’, phenoperidine ‘inn’, pipradol ‘inn’, piritramide ‘inn’, pr 5 4 3 2