反应详情

The compound (1S,2S)-(1-{[benzyloxycarbonyl-(2,4-dimethyl-benzyl)-amino]-methyl}-2-hydroxy-pentyl)-carbamic acid tert-butyl ester (580 mg, 1.2 mmol, see procedure 12a) was dissolved in CH2Cl2 (9 mL) and treated with TFA (3 mL). The solution was stirred for 3 h and then concentrated in vacuo. The residue was dissolved in benzene and concentrated in vacuo; this procedure was repeated to provide [(2S,3S)-2-amino-3-hydroxy-hexyl]-(2,4-dimethyl-benzyl)-carbamic acid benzyl ester. The amine was dissolved in 12 mL of 2:1 CH2Cl2/DMF. The resultant solution was charged sequentially with mono-benzyl malonate (232 mg, 1.2 mmol), N,N-diisopropylethylamine (1.05 mL, 6.0 mmol) and HATU (547 mg, 1.4 mmol). The mixture was stirred for 12 h at RT, concentrated in vacuo, and partitioned between EtOAc and sat. NH4Cl. The aqueous phase was extracted with EtOAc (1×). The combined organic extracts were washed with sat. NaHCO3 and brine, dried (Na2SO4), filtered, and concentrated in vacuo. The residue was purified by flash chromatography to provide N-[(1S,2S)-(1-{[benzyloxycarbonyl-(2,4-dimethyl-benzyl)-amino]-methyl}-2-hydroxy-pentyl)]-malonamic acid benzyl ester (517 mg, 77% yield). MS found: (M+Na)+=583.4. (17b) The compound N-[(1S,2S)-(1-{[benzyloxycarbonyl-(2,4-dimethyl-benzyl)-amino]-methyl}-2-hydroxy-pentyl)]-malonamic acid benzyl ester (517 mg, 0.92 mmol) was dissolved in THF (57 mL). This solution was charged sequentially with MeOH (19 mL) and aq. LiOH (44 mg LiOH in 19 mL water) and stirred for 12 h at RT. The mixture was concentrated in vacuo, and the residue was lyophilized from 1:1 acetonitrile/water to provide the lithium salt of N-[(1S,2S)-1-{[benzyloxycarbonyl-(2,4-dimethyl-benzyl)-amino]-methyl}-2-hydroxy-pentyl]-malonamic acid as a white powder (420 mg, 97% yield). A portion of this material (39 mg, 0.22 mmol) was dissolved in 4 mL of 1:1 CH2Cl2/DMF. The resultant solution was charged sequentially with 4-methyl-3-trifluoromethylaniline (105 mg, 0.22 mmol), N,N-diisopropylethylamine (0.19 mL, 1.1 mmol) and HATU (102 mg, 0.27 mmol). The mixture was stirred for 12 h at RT, concentrated in vacuo, and partitioned between EtOAc and sat. NH4Cl. The aqueous phase was extracted with EtOAc (1×). The combined organic extracts were washed with sat. NaHCO3 and brine, dried (Na2SO4), filtered, and concentrated in vacuo. The residue was dissolved in MeOH (3 mL). This solution was charged with 5% Pd/C, Degussa style (11 mg), stirred under H2 (1 atm) for 12 h at RT, filtered, and concentrated in vacuo. Purification of the residue by reverse-phase HPLC provided the title compound as a white powder after lyopholization. MS found: (M+H)+=494.4.

1. concentrationconcentrated in vacuo
2. custompartitioned between EtOAc and sat. NH4Cl
3. extractionThe aqueous phase was extracted with EtOAc (1×)
4. washThe combined organic extracts were washed with sat. NaHCO3 and brine
5. dry with materialdried (Na2SO4)
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customThe residue was purified by flash chromatography