反应详情

A stirred solution of cyclopentylacetic acid (2 ml, 0.0159 mol) and triethylamine (2.28 ml, 0.0163 mol) in THF (120 ml) was cooled to -8° C. and treated, dropwise with isobutyl chloroformate (2.12 ml, 0.0163 mol). The mixture was kept at -8° C. for 1.5 hour and then treated with a mixture of the product from Example 7, Step II, (4.0 g, 0.014 mol) and triethylamine (2.28 ml, 0.0163 mol) in THF (160 ml). It was kept at -8° C. for 1.5 hour and then treated slowly with 1N HCl (158 ml). The product was extracted with EtOAc. The extract was washed successively with water, saturated aqueous NaHCO3 and brine, dried (MgSO4) and concentrated. The residue was chromatographed on silica gel with 5% MeOH--CH2Cl2 to give 3.0 g of N-(4-(4-(ethyl(cyclopentylacetyl)amino)-1-hydroxybutyl)phenyl)methanesulfonamide. The mass spectrum had m/z 396 (M+).

1. waitIt was kept at -8° C. for 1.5 hour
2. extractionThe product was extracted with EtOAc
3. washThe extract was washed successively with water, saturated aqueous NaHCO3 and brine
4. dry with materialdried (MgSO4)
5. concentrationconcentrated
6. customThe residue was chromatographed on silica gel with 5% MeOH