3.8.4. Derivatization of Compound **1**

Compound **1** (0.5 mg) was combined with 1.0 mg of Pd/C in 1 mL EtOH and stirred under an atmosphere of H2 for 8 h. The mixture was filtered through glass wool, rinsed with EtOH (3 × 1.0mL), and concentrated in vacuo.

Hydrogenated compound **1** (0.25 mg) was dissolved in 1 mL CH2Cl2, into which a stream of ozone gas was bubbled at −78 ◦C for 25 min. The reaction was concentrated under vacuum, and the residue was treated with 1 mL of 1:2 35% H2O2:HCOOH at 70 ◦C and ambient atmosphere for 20 min. The reaction was again concentrated in vacuo, followed by the addition of 1 mL 6 M HCl. The reaction mixture was stirred in a sealed vial with ambient atmosphere overnight at 110 ◦C, and then concentrated under vacuum. To the residue, a solution of l-FDAA (0.6 mg, 2 μmol) in acetone (200 μL) and 0.1 M NaHCO3 (200 μL) were added. The reaction mixture was sealed in a vial with ambient atmosphere, stirred at 90 ◦C for 5 min, neutralized with 6 M HCl, concentrated in vacuo, and prepared for LC-MS analysis.

Hydrogenated compound **1** (0.25 mg) was dissolved in 1 mL 6 M HCl. This reaction mixture was stirred in a sealed vial with ambient atmosphere overnight at 110 ◦C, and then concentrated under vacuum. The residue was combined with HATU (0.4 mg, 1 μmol), (*S*)-(+)-2-phenylglycine methyl ester hydrochloride (0.2 mg, 1 μmol), and DIPEA (20 μL) in DMF (200 μL) and stirred for 6 h at room temperature and at ambient atmosphere. The reaction mixture was then diluted with 1.0 mL of EtOAc, washed with saturated aqueous NH4Cl (3 × 1.0 mL), concentrated under vacuum, and prepared for LC-MS analysis.
