反应详情

温度

45 °C

(±)-2-Amino-5-phenylpentanoic acid (35 g) was suspended in water (3 L) and solubilized by adjusting the pH to 12 with 7N sodium hydroxide solution. The pH was readjusted to pH 8 using 1M phosphoric acid with continuous stirring at 45° C. The solution was allowed to cool to 40° C. and L-amino acid oxidase (Sigma, 0.7 unit/mg) was added. The reaction was stirred with good aeration at 37°-40° C. for two weeks. The reaction was monitored using the following High Pressure Liquid Chromatography (HPLC) system: C-18 Waters analytical column, 20% acetonitrile in Buffer (0.624 g/L CuSO4.5H2O, 0.576 g/L L-proline, 2 g/L ammonium acetate, and 1L of water with the pH of the solution adjusted to pH 7 with ammonium hydroxide); 2 mL/minute flow rate; fluorescence detection: Ex 345 nm, Em>415 nm; OPA derivatization: 300 μL of 1N sodium borate pH 9.4, 50 mL of 20 mg ortho-phthalaldehyde (OPA) plus 24 ng N-acetyl cysteine/6 mL 50% methanol/water; incubate 3 minutes at ambient temperature. When the digestion of the L-enantiomer was complete, the reaction mixture was concentrated to 500 mL by removing water in vacuo. The pH was adjusted to 5 and the predpitate was collected by filtration and recrystallization from ethanol-water to afford 17.32 g (99%) of the title compound.

1. temperatureto cool to 40° C.
2. stirringThe reaction was stirred with good aeration at 37°-40° C. for two weeks
3. customincubate 3 minutes
4. customat ambient temperature
5. concentrationthe reaction mixture was concentrated to 500 mL
6. customby removing water in vacuo
7. filtrationthe predpitate was collected by filtration and recrystallization from ethanol-water