H-D-CHA-OH

White to off-white crystalline powder

General procedure: A mixture of pyridoxamine 4a (2.1 mg, 0.0050 mmol), 4-(naphthalen-1-yl)-2-oxobutanoic acid (1a) (22.8 mg, 0.10 mmol), 2, 2-diphenylglycine 11 (22.7 mg, 0.10 mmol), CH3COOH (48.0 mg, 0.80 mmol), EtOH (0.40 mL), and H2O (0.10 mL) was stirred at 25 °C for 24 h. The reaction mixture was transferred to a 25-mL eggplant-shaped flask. Methanol (10 mL) was added to dissolve the solid completely and silica gel (0.50 g) was added. The solvent was removed under reduced pressure at 25 oC. The residue was submitted to flash column chromatography (silica gel, EtOH / ethyl acetate / 25-28percent ammonia solution = 100:58:16) to give amino acid 2a (22.0 mg, 96percent yield, 83percent ee) as a white solid. The enantiomeric excess (ee) of 2a was determined by HPLC analysis after the amino acid was converted to the corresponding methyl ester by treatment with diazomethane in methanol at room temperature (Chiralcel OD-H, Hex:i-PrOH = 85:15, 1.0 mL/min). The enantiomeric excesses (ee’s) of products 2b-l and 2o and the dr values of products 2m-n were determined by HPLC analysis after the amino acids were converted to the corresponding N-benzoyl methyl esters by treatment with thionyl chloride in methanol and subsequent reaction with benzoic anhydride.To a 5 mL vial equipped with a magnetic stirrer bar were added 3-cyclohexyl-2-oxopropanoic acid (1j) (0.0510 g, 0.30 mmol), 2, 2-diphenylglycine (2) (0.0681 g, 0.30 mmol), chiral pyridoxamine 6g (0.0195 g, 0.030 mmol), and MeOH-H2O (8:2) (3.0 mL). The mixture was stirred at 20 °C for 3 days. The reaction mixture was transferred to a 25 mL round-bottom flask and MeOH was added until all the solid was dissolved. Then silica gel (0.50 g) was added. After removal of the solvent in vacuo at 20 °C, the resulting residue was submitted to column chromatography on silica gel (EtOH/ethyl acetate/25-28percent ammonia solution =100:58:16) to give compound 3j (0.0401 g, 78percent yield, 52percent ee) as a white solid. The enantiomeric excesses of 3b-k were deteremined by HPLC analysis after being converted to N-benzoyl methyl esters by treatment with thionyl chloride in methanol and subsequent reaction benzoyl chloride.7 The enantiomeric excess of 3a was deteremined by HPLC analysis after being converted to its methyl ester by treatment with CH2N2 in methanol.

Molecular Weight:171.24
XLogP3:-0.3
Hydrogen Bond Donor Count:2
Hydrogen Bond Acceptor Count:3
Rotatable Bond Count:3
Exact Mass:171.125928785
Monoisotopic Mass:171.125928785
Topological Polar Surface Area:63.3
Heavy Atom Count:12
Complexity:153
Defined Atom Stereocenter Count:1
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes