Start with an oxolane (tetrahydrofuran) ring, numbered O1-C2-C3-C4-C5 clockwise (O1 is the ring oxygen). The ring has three stereocenters:

- C2 (R): bears a hydroxymethyl group (-CH2OH).
- C3 (S): bears a hydroxyl group.
- C5 (R): bears a pyridine ring (a six-membered aromatic ring with one nitrogen) attached at a carbon such that the pyridine nitrogen is meta to the attachment point. On this pyridine, the carbon para to the attachment point carries an N,N-dimethylamino group, described as a nitrogen atom bonded to two methyl groups.