tert-butyl N-[(4-aminophenyl)methyl]carbamate

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

Procedure: Analogously to Example 1, Process step 1, 33 mg (0.15 mmol) of tert-butyl (4-aminobenzyl)carbamate and 43 mg (0.15 mmol) of (2R,3S)-3-benzoylamino-2-hydroxy-3-phenylpropionic acid were dissolved in 1 ml of DCM and 1 ml of DMF and treated successively with 78 μl of DIPEA (0.45 mmol), 22.5 mg of HOAt (0.165 mmol) and 76.9 mg (0.165 mmol) of PyBrop. Without further work-up, the batch obtained was filtered and then purified using HPLC. The product-containing fractions were lyophilized. Without further work-up, the batch obtained was filtered purified

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

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

Procedure: To a mixture of (4-amino-benzyl)-carbamic acid tert-butyl ester (4.8 g, 21.6 mmol) and calcium carbonate (2.7 g, 27 mmol) in methanol (60 mL) was added iodine (5.5 g, 21.6 mmol) in portions. The mixture was heated at reflux overnight and then concentrated in vacuo to give a dark brown residue, which was partitioned between ethyl acetate and saturated sodium bisulfite solution. The organic phase was washed with water and brine, dried over Na2SO4 and filtered. The filtrate was concentrated in vacuo to give a residue, which was purified by chromatography (5%-20% ethyl acetate in hexanes) to give 3.5 g (47%) of the desired product as a brown semi-solid. MS(APCI+): m/z 349.1 (MH+). The mixture was heated at reflux overnight concentrated in vacuo to give a dark brown residue, which was partitioned between ethyl acetate and saturated sodium bisulfite solution The organic phase was washed with water and brine dried over Na2SO4 filtered The filtrate was concentrated in vacuo to give a residue, which was purified by chromatography (5%-20% ethyl acetate in hexanes)

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

Procedure: To a mixture of (4-amino-benzyl)-carbamic acid tert-butyl ester (4.8 g, 21.6 mmol) and calcium carbonate (2.7 g, 27 mmol) in methanol (60 mL) was added iodine (5.5 g, 21.6 mmol) in portions. The mixture was heated at reflux overnight and then concentrated in vacuo to give a dark brown residue, which was partitioned between ethyl acetate and saturated sodium bisulfite solution. The organic phase was washed with water and brine, dried over Na2SO4 and filtered. The filtrate was concentrated in vacuo to give a residue, which was purified by chromatography (5%-20% ethyl acetate in hexanes) to give 3.5 g (47%) of the desired product as a brown semi-solid. MS(APCI+): m/z 349.1 (MH+). The mixture was heated at reflux overnight concentrated in vacuo to give a dark brown residue, which was partitioned between ethyl acetate and saturated sodium bisulfite solution The organic phase was washed with water and brine dried over Na2SO4 filtered The filtrate was concentrated in vacuo to give a residue, which was purified by chromatography (5%-20% ethyl acetate in hexanes)

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

Procedure: To a stirred solution of tert-butyl N-(4-aminobenzyl)carbamate (6.00 g, 27.0 mmol) in anhydrous THF (50 ml) was added benzoylisothiocyanate (4.43 g, 27.0 mmol). The solution was stirred for 2 hours and the solvent removed in vacuo to yield 100% (10.4 g) of the protected thiourea as a yellow solid: m.p. 161-163° C.; 1H-NMR (CDCl3) δ 1.45 (9H, s), 4.33 (2H, d), 4.85 (1H, broad), 7.34 (2H, d), 7.60 (5H, m), 7.90 (2H, d), 9.13 (1H, s), 12.58 (1H, s); 386 (ESMS, MH+). the solvent removed in vacuo

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

Procedure: To a stirred solution of tert-butyl N-(4-aminobenzyl)carbamate (6.00 g, 27.0 mmol) in anhydrous THF (50 ml) was added benzoylisothiocyanate (4.43 g, 27.0 mmol). The solution was stirred for 2 hours and the solvent removed in vacuo to yield 100% (10.4 g) of the protected thiourea as a yellow solid: m.p. 161-163° C.; 1H-NMR (CDCl3) δ 1.45 (9H, s), 4.33 (2H, d), 4.85 (1H, broad), 7.34 (2H, d), 7.60 (5H, m), 7.90 (2H, d), 9.13 (1H, s), 12.58 (1H, s); 386 (ESMS, MH+). the solvent removed in vacuo

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of 4-(N-tert-butoxycarbonylaminomethyl)aniline (756 mg, 3.4 mmol), 3-[4-(biphenyl-2-ylcarbamoyloxy)piperidin-1-yl]propionic acid (1.5 g, 4.08 mmol; prepared as described in Preparation 11) and HATU (1.55 g, 4.08 mmol) in DMF (6.8 mL), was added DIPEA (770 μL, 4.42 mmol). The reaction mixture was stirred at 50° C. overnight, and then the solvent was removed under reduced pressure. The resulting residue was dissolved in DCM (20 mL) and washed with saturated aqueous sodium bicarbonate solution (10 mL). The organic phase was then dried over MgSO4 and the solvent was removed under reduced pressure. The crude product was purified by flash chromatography (5-10% MeOH/DCM) to give a solid, which was dissolved in TFA/DCM (25%, 30 mL) and stirred at room temperature for 2 hours. The solvent was then removed under reduced pressure and the crude residue was dissolved in DCM (30 mL) and washed with 1N NaOH (15 mL). The organic phase was separated, dried over MgSO4, filtered and the solvent was removed under reduced pressure to give 1.5 g of the title intermediate (94% yield over 2 steps). the solvent was removed under reduced pressure The resulting residue was dissolved in DCM (20 mL) washed with saturated aqueous sodium bicarbonate solution (10 mL) The organic phase was then dried over MgSO4 the solvent was removed under reduced pressure The crude product was purified by flash chromatography (5-10% MeOH/DCM) to give a solid, which stirred at room temperature for 2 hours The solvent was then removed under reduced pressure the crude residue was dissolved in DCM (30 mL) washed with 1N NaOH (15 mL) The organic phase was separated dried over MgSO4 filtered the solvent was removed under reduced pressure

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: C4 (7.0 g, 27.7 mmol) was dissolved in dioxane (325 mL), ethanol (240 mL), and water (160 mL). The resultant solution was then treated with Fe(0) powder (7.12 g, 127.4 mmol) and ammonium chloride (5.33 g, 99.7 mmol), and the resultant mixture was stirred at 70° C. for 4 hours. The reaction mixture was cooled to 25° C., filtered through Celite®, and washed with EtOAc. The organic solvents were evaporated, and the resultant aqueous residue was extracted with EtOAc. The combined organic layers were dried over MgSO4, filtered, and concentrated to provide C5 as a yellow solid. Yield: 6.52 g, 99% yield. 1H NMR (400 MHz, d6-DMSO) δ: 7.146 (t, 1H), 6.87 (d, 2H), 6.48 (d, 2H), 4.95 (s, 2H), 3.92 (d, 2H), 1.38 (s, 9H). filtered through Celite® washed with EtOAc The organic solvents were evaporated the resultant aqueous residue was extracted with EtOAc The combined organic layers were dried over MgSO4 filtered concentrated

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

Procedure: According to the Step 70-5 in the synthetic method for EXAMPLE 70, compound 70-4 (50 mg) was treated with tert-butyl 4-aminobenzylcarbamate (37 mg) to afford compound 71-1 (58 mg) as white solid after preparative LC purification.