反应详情

温度

-15 °C

(3S,4S)-3-{N-benzyloxycarbonyl-β-(2-naphthyl)-L-alanyl}-amino-4-acetoxy-azetidin-2-one (237 mg, 0.5 mmol) obtained in example 8, was hydrogenated with 400 mg of 10% palladium on activated carbon in ethyl acetate (20 ml) and THF (10 ml) at 50 psi hydrogen pressure at room temperature for 2 hrs. After removal of catalyst by filtration, the desubstituted (3S,4S)-3{β-(2-naphthyl)-L-alanyl}-amino-4-acetoxy-azetidin-2-one was cooled to -15° C. Then triethylamine (50 mg, 0.5 mmol) and trans-2-phenyl-eth-1-ene sulfonyl chloride (101 mg, 0.5 mmol) were added at -15° C. Stirring was continued at a bath temperature of -10 to 0° C. for 1 hr and 5° C. overnight. The reaction mixture was diluted with ethyl acetate, washed with cold saturated NaHCO3 solution, water, brine and dried over sodium sulfate. After removal of solvent, the residue was purified by silica gel column chromatography using hexane-ethyl acetate (1:1) as eluent and the title compound (30 mg) was obtained.

1. customAfter removal of catalyst
2. filtrationby filtration
3. customwas continued at a bath
4. custom5° C. overnight
5. washwashed with cold saturated NaHCO3 solution, water, brine
6. dry with materialdried over sodium sulfate
7. customAfter removal of solvent
8. customthe residue was purified by silica gel column chromatography