D-Threonine → HCID 86699933, compound

To a stirred mixture of D-threonine (0.150 g, 1.25 mmol) and NaHCO3 (0.158 g, 1.89 mmol) in H2O (3.5 mL), the crude mixture containing cyclohexyl-2-pyridyl-carbonate and cyclohexyl-2-oxopyridine 1-carboxylate (0.418 g, 1.89 mmol) in THF (3.5 mL) was added. After 15 h at rt the crude mixture was rotary evaporated to remove the organics and subsequently extracted with Et2O (3×5 mL). The aqueous phase was acidified with 2M HCl solution to pH 2-3 and subsequently extracted with AcOEt (3×10 mL). The organic fraction was dried over Na2SO4, filtered and concentrated to dryness to afford the title compound (0.3 g, 97%) as transparent oil, which was used in the next step without further purification. MS (ESI) m/z: 246 [M−H]+; (ESI) m/z: 244 [M−H]−. 1H NMR (DMSO-d6): δ 1.09 (d, J=6.2 Hz, 3H), 1.16-1.43 (m, 5H), 1.49 (s, 1H), 1.69 (s, 2H), 1.80 (s, 2H), 3.93 (dd, J=2.9, 8.8 Hz, 1H), 3.99-4.12 (m, 1H), 4.44-4.61 (m, 1H), 6.59 (d, J=8.9 Hz, 1H), 12.32 (br s, 1H).

1. additionwas added
2. customAfter 15 h at rt the crude mixture was rotary evaporated
3. customto remove the organics and
4. extractionsubsequently extracted with Et2O (3×5 mL)
5. extractionsubsequently extracted with AcOEt (3×10 mL)
6. dry with materialThe organic fraction was dried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated to dryness

ORD record

ord-8182c1f549744b14b2c5523d46238882

Source dataset

uspto-grants-2016_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09353075B2