Hydrazine hydrate (1:1) → 4-{(S)-1-[(S)-6-(2-Hydroxy-2-methyl-propyl)-2-oxo-6-phenyl-[1,3]oxazinan-3-yl]-ethyl}-benzoic acid hydrazide

TBTU [2-(1H-benzotriazol-1-yl)-1,1,3,3-tetramethyluronium tetrafluoroborate, 0.33 g] was added to 4-{(S)-1-[(S)-6-(2-hydroxy-2-methyl-propyl)-2-oxo-6-phenyl-[1,3]oxazinan-3-yl]-ethyl}-benzoic acid (0.37 g) and EtNiPr2 (0.41 mL) dissolved in dimethylformamide (5 mL). After stirring the solution at room temperature for 10 min, hydrazine hydrate (0.23 mL) was added. The solution was stirred at room temperature overnight and then diluted with water. The resulting mixture was extracted with ethyl acetate and the combined extracts were washed with brine and dried (MgSO4). The solvent was removed and the residue was purified by chromatography on silica gel (CH2Cl2/MeOH 98:2→90:10) to afford the title compound as a colorless foam-like solid.

1. stirringThe solution was stirred at room temperature overnight
2. extractionThe resulting mixture was extracted with ethyl acetate
3. washthe combined extracts were washed with brine
4. dry with materialdried (MgSO4)
5. customThe solvent was removed
6. customthe residue was purified by chromatography on silica gel (CH2Cl2/MeOH 98:2→90:10)

ORD record

ord-a861102933604e0fbdf951893e9ab35c

Source dataset

uspto-grants-2013_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08575156B2