| Code | Name | Deposits | Targets | Ligand Type |
|---|---|---|---|---|
| Ni | unknown | 1 | 1 | biological |
| NI | 3 | 3 | biological | |
| NI | 10 | 8 | crystallization | |
| NI | 4 | 3 | other | |
| NIO | nicotinic acid | 1 | 1 | biological |
| NMY | neomycin | 1 | 1 | biological |
| NO2 | nitrite ion | 1 | 1 | crystallization |
| NO3 | 3 | 3 | crystallization | |
| NPO | 1 | 1 | crystallization | |
| NVA | norvaline | 1 | 1 | crystallization |
| NXL | (2s,5r)-1-formyl-5-[(sulfooxy)amino]piperidine-2-carbox amide | 1 | 1 | biological |
| NXP | n-{4-[(1e)-n-carbamimidoylethanehydrazonoyl]phenyl}-1h-indole-3-carboxamide | 2 | 1 | crystallization |
| OAA | oxaloacetate ion | 1 | 1 | biological |
| OCA | 2 | 2 | biological | |
| OCS | cysteinesulfonic acid | 1 | 1 | other |
| OPE | 1 | 1 | biological | |
| OXP | 2-oxo-3-pentenoic acid | 2 | 2 | biological |
| P18 | 2 | 2 | biological | |
| P18 | 1 | 1 | crystallization | |
| P1T | 4 | 1 | biological |