| Record No. | Name | No. of Entries |
| 551 | Nicospan | 1 |
| 552 | Nitidine | 8 |
| 553 | Nor-Coralyne | 1 |
| 554 | Norapomorphine | 2 |
| 555 | Norbuprenorphine | 1 |
| 556 | Norcoralydine | 1 |
| 557 | Nordicentrine | 1 |
| 558 | Norglaucin | 1 |
| 559 | Norlaudanosoline-1-carboxylic acid | 1 |
| 560 | Norlaureline | 1 |
| 561 | Nornuciferine | 1 |
| 562 | Norreticuline | 1 |
| 563 | Norsanguinarine | 1 |
| 564 | Norstephalagine | 1 |
| 565 | Noscapine | 2 |
| 566 | Noscapine hydrochloride | 2 |
| 567 | NSC 186305 | 1 |
| 568 | NSC 264062 | 1 |
| 569 | NSC 309696 | 1 |
| 570 | NSC11429 | 1 |
| 571 | NSC118072 | 1 |
| 572 | NSC118078 | 1 |
| 573 | NSC148830 | 1 |
| 574 | NSC153190 | 1 |
| 575 | NSC168212 | 1 |