Phosphoric Acid → D-2-Amino-5-phenyl-pentanoic acid

HRID 1376392Notes

Reaction equation

HRID 1376392 reaction equation
[NH2:1][CH:2]([CH2:6][CH2:7][CH2:8][C:9]1[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=1)[C:3]([OH:5])=[O:4].[OH-].[Na+].P(=O)(O)(O)O.N1CCC[C@H]1C(O)=O.C([O-])(=O)C.[NH4+].[OH-].[NH4+].C1C=CC(C=O)=C(C=O)C=1.B([O-])([O-])[O-].[Na+].[Na+].[Na+].C(N[C@H](C(O)=O)CS)(=O)C.CC1(C)O[C@]2(OC[C@@H]3OC(C)(C)O[C@@H]3C2=O)CO1>O.C(#N)C>[NH2:1][C@H:2]([CH2:6][CH2:7][CH2:8][C:9]1[CH:10]=[CH:11][CH:12]=[CH:13][CH:14]=1)[C:3]([OH:5])=[O:4]

Participants

13

Reactant 10

HCID 1004Phosphoric AcidHCID 4807Phthalaldehyde2×HCID 12035N-Acetyl-L-CysteineHCID 14798Sodium HydroxideHCID 14923Ammonium HydroxideHCID 145742L-ProlineHCID 159383boric acid, sodium saltHCID 2968662-Amino-5-phenylpentanoic acidHCID 517165Ammonium AcetateHCID 11391247L-enantiomer

Product 1

HCID 6993756D-2-Amino-5-phenyl-pentanoic acidYield 99%

Reagents, catalysts & solvents 2

HCID 962WaterSolvent2×HCID 6342AcetonitrileSolvent

Conditions

Temperature
45 °C

Procedure

(±)-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.

Workup

  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

Sources & evidence

ORD record
ord-8624145a891240cfad2ce76919e56f2d
Source dataset
uspto-grants-1997_09
Patent number
US05663148

Reaction notes

Loading…