chloromethyl butanoate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred mixture of (4S)-1,4-dihydro-2,6-dimethyl-4-(2',3'-dichorophenyl)-5-carboxymethyl-3-pyridinecarboxylic acid (2.0 g, 5.61 mmol) and sodium bicarbonate (0.96 g, 11.4 mmol) in DMF (100 ml) under nitrogen atmosphere was added chloromethyl butyrate (1.16 g, 8.5 mmol). The reaction mixture was heated at 80° C. for 23 h. Workup by filtration followed by evaporation of solvent. The crude residue was dissolved in dichloromethane and washed with sodium bicarbonatesolution. The organic phase was dried over sodium sulfate and evaporated. Recrystallization first from a mixture of 45% ethylacetate in isooctane followed by diisopropylether gave colorless crystals (1.08 g, 42%), mp. 128°-129° C. NMR spectral data are identical with the data of the racemate as shown in Example 3. [α]D20 =-21.50 (1 % in methanol). Workup by filtration followed by evaporation of solvent The crude residue was dissolved in dichloromethane washed with sodium bicarbonatesolution The organic phase was dried over sodium sulfate evaporated Recrystallization first from a mixture of 45% ethylacetate in isooctane

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred mixture of (4R)-1,4-dihydro-2,6-dimethyl-4-(2',3'-dichorophenyl)-5-carboxymethyl-3-pyridinecarboxylic acid (2.93 g, 8.23 mmol) and sodium bicarbonate (1.38 g, 16.5 mmol) in DMF (150 ml) under nitrogen atmosphere was added chloromethyl butyrate (1.72 g, 12.6 mmol). The reaction mixture was heated at 80° C. for 17 h. Workup by filtration followed by evaporation of solvent. The crude residue was chromatographed on silica gel with 5% ethyl acetate in dichloromethane. Recrystallization from diisopropylether gave colorless crystals (2.62 g, 70%), mp. 128°-129° C. NMR spectral data are identical with the data of the racemate as shown in Example 3. [α]D20 =+17.5° (1% in methanol). Workup by filtration followed by evaporation of solvent The crude residue was chromatographed on silica gel with 5% ethyl acetate in dichloromethane Recrystallization from diisopropylether

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred mixture of 1,4-dihydro-2,6-dimethyl-4-(2',3'-dichorophenyl)-5-carboxymethyl-3-pyridinecarboxylic acid (2.62 g, 7.35 mmol) and sodium bicarbonate (1.26 g, 15 mmol) in DMF (130 ml) under nitrogen atmosphere was added chloromethyl butyrate (1.53 g, 11.21 mmol). The reaction mixture was heated at 80° C. for 24 h. Workup by filtration followed by evaporation of solvent. The crude residue was chromatographed on silica gel with 45% ethyl acetate in isooctane. Recrystallization from diisopropylether gave colorless crystals (2.20 g, 66%), mp. 136.2°-138.5° C. 1H-NMR (CDCl3): 7.30-7.03 (m, 3H); 5.89 (s, 1H); 5.74 (d, J=5.5 Hz, 1H); 5.70 (d, J=5.5 Hz, 1H); 5.46 (s, 1 H); 3.60 (s, 3H); 2.33 (m, 8H); 1.65-1.55 (m, 2H); 0.90 (t, J=7.4 Hz, 3H).13C-NMR (CDCl3): 172.25; 167.61; 165.80; 147.43; 146.59; 143.82; 132.89; 131.11; 129.82; 128.30; 126.95; 103.97; 101.99; 78.63; 50.92; 38.49; 35.79; 19.91; 19.30; 18.01; 13.50. Workup by filtration followed by evaporation of solvent The crude residue was chromatographed on silica gel with 45% ethyl acetate in isooctane Recrystallization from diisopropylether

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of chloromethyl butyrate (20.5 μL, 164 μmol) and NaI (24.5 mg, 164 μmol) in acetone (2.0 mL, 27 mmol) was stirred at 60° C. for 1 hour, then cooled to room temperature and added to a mixture of (R)-3-[N-(3′-chlorobiphenyl-4-ylmethyl)-N′-(3-hydroxyisoxazole-5-carbonyl)hydrazino]-2-hydroxypropionic acid 2-oxo-2-phenylethyl ester (30.0 mg, 54.5 μmol) and Et3N (38.0 μL, 273 μmol) in acetone (1 mL). The resulting mixture was stirred at room temperature for 2 hours, concentrated, dissolved in AcOH (2 mL), filtered, and purified by reverse phase preparative HPLC. The desired fractions were combined and lyophilized. Zinc (178 mg, 2.7 mmol) and AcOH (1.0 mL, 18 mmol) was added and the resulting mixture was stirred at room temperature for 2 hours. The mixture was filtered and purified by reverse phase preparative HPLC to yield the title compound (2.5 mg). MS m/z [M+H]+ calc'd for C25H26ClN3O8, 532.14. found 532.2. cooled to room temperature The resulting mixture was stirred at room temperature for 2 hours concentrated dissolved in AcOH (2 mL) filtered purified by reverse phase preparative HPLC the resulting mixture was stirred at room temperature for 2 hours The mixture was filtered purified by reverse phase preparative HPLC

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of chloromethyl butyrate (20.5 μL, 164 μmol) and NaI (24.5 mg, 164 μmol) in acetone (2.0 mL, 27 mmol) was stirred at 60° C. for 1 hour, then cooled to room temperature and added to a mixture of (R)-3-[N-(3′-chlorobiphenyl-4-ylmethyl)-N′-(3-hydroxyisoxazole-5-carbonyl)hydrazino]-2-hydroxypropionic acid 2-oxo-2-phenylethyl ester (30.0 mg, 54.5 μmol) and Et3N (38.0 μL, 273 μmol) in acetone (1 mL). The resulting mixture was stirred at room temperature for 2 hours, concentrated, dissolved in AcOH (2 mL), filtered, and purified by reverse phase preparative HPLC. The desired fractions were combined and lyophilized. Zinc (178 mg, 2.7 mmol) and AcOH (1.0 mL, 18 mmol) was added and the resulting mixture was stirred at room temperature for 2 hours. The mixture was filtered and purified by reverse phase preparative HPLC to yield the title compound (2.5 mg). MS m/z [M+H]+ calc'd for C25H26ClN3O8, 532.14. found 532.2. cooled to room temperature The resulting mixture was stirred at room temperature for 2 hours concentrated dissolved in AcOH (2 mL) filtered purified by reverse phase preparative HPLC the resulting mixture was stirred at room temperature for 2 hours The mixture was filtered purified by reverse phase preparative HPLC

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of chloromethyl butyrate (6.8 μL, 54.5 μmol) and NaI (8.2 mg, 54.5 μmol) in acetone (0.5 mL, 7 mmol) was stirred at 60° C. for 1 hour, then it was added to a mixture of (R)-3-[N-(5′-chloro-2′-fluorobiphenyl-4-ylmethyl)-N′-(2-trityl-2H-tetrazole-5-carbonyl)hydrazino]-2-hydroxypropionic acid (12.3 mg, 18.2 μmol) and DIPEA (4.8 μL, 27.2 μmol) in acetone (0.5 mL). The resulting mixture was stirred at 40° C. for 2 hours, concentrated and partitioned between EtOAc (10 mL) and water (2 mL). The organic layer was dried over MgSO4, filtered, and concentrated. 4.0 M HCl in 1,4-dioxane (40.0 μL, 160 μmol) in MeCN (0.2 mL, 4 mmol) was added and the resulting mixture was stirred at room temperature for 20 minutes. The mixture was concentrated and the residue was dissolved in AcOH (1.5 mL), filtered, and purified by reverse phase preparative HPLC to yield the title compound (1.3 mg). MS m/z [M+H]+ calc'd for C23H24ClFN6O6, 535.14. found 535.1. The resulting mixture was stirred at 40° C. for 2 hours concentrated partitioned between EtOAc (10 mL) and water (2 mL) The organic layer was dried over MgSO4 filtered concentrated the resulting mixture was stirred at room temperature for 20 minutes The mixture was concentrated the residue was dissolved in AcOH (1.5 mL) filtered purified by reverse phase preparative HPLC

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of (R)-3-[N-(5′-chloro-2′-fluorobiphenyl-4-ylmethyl)-N′-(5-oxo-1-phenyl-4,5-dihydro-1H-[1,2,4]triazole-3-carbonyl)hydrazino]-2-hydroxypropionic acid (200 mg, 335 μmol) in dry DMF (6 mL) was added chloromethyl butyrate (68 mg, 503 mmol), NaI (101 mg, 670 mmol), and 2,6-dimethylpyridine (143 mg, 1.3 mmol) in portions at room temperature. The resulting mixture was stirred at room temperature for 8 hours. Water (12 mL) was added and the mixture was extracted with EtOAc (3×20 mL). The combined organic layers were dried over anhydrous Na2SO4 and concentrated in vacuo. The residue was purified by column chromatography (PE:EtOAc=3:1) to yield the title compound as a white solid (21 mg). LC-MS: 625.9 [M+H]+. 1H NMR (DMSO-d6, 400 MHz) δ 0.84 (t, J=7.4 Hz, 3H), 1.45-1.56 (m, 2H), 2.29 (t, J=7.3 Hz, 2H), 3.31-3.17 (m, 2H), 4.18-4.35 (m, 2H), 4.35 (t, J=5.3 Hz, 1H), 5.68-5.79 (m, 2H), 7.28 (t, J=7.4 Hz, 1H), 7.34-7.40 (m, 1H), 7.43-7.55 (m, 7H), 7.58 (dd, J=6.8, 2.6 Hz, 1H), 7.90 (d, J=7.6 Hz, 2H), 9.98 (s, 1H), 12.76 (s, 1H). the mixture was extracted with EtOAc (3×20 mL) The combined organic layers were dried over anhydrous Na2SO4 concentrated in vacuo The residue was purified by column chromatography (PE:EtOAc=3:1)