benzyl (2S)-2-amino-3-phenylpropanoate

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

Procedure: To N-(toluene-4-sulfonyl)-L-alanine (2.0 mmoles) in DMF (10 mL) was added BOP (2.1 mmoles) and N-methylmorpholine (4.0 mmoles) and the reaction stirred at room temperature for 45 minutes. L-Phenylalanine benzyl ester (2.0 mmoles) was added and the reaction stirred for 16 hours at room temperature. The reaction mixture was extracted with water (100 mL) and diethyl ether (3×50 mL) The combined organic layers were successively washed with 0.2 N HCl (2×50 mL), sat. NaHCO3 (50 mL), and sat. NaCl (50 mL). The organic layer was dried over MgSO4, filtered, and concentrated to yield a colorless oil (387 mg, 40%). The crude product was purified by silica gel chromatography (50% EtOAc /Hexane, Rf=0.61). The title compound was crystalized from CHCl3/Hexane to yield a white solid, mp=109-110° C. the reaction stirred for 16 hours at room temperature The reaction mixture was extracted with water (100 mL) and diethyl ether (3×50 mL) The combined organic layers were successively washed with 0.2 N HCl (2×50 mL), sat. NaHCO3 (50 mL), and sat. NaCl (50 mL) The organic layer was dried over MgSO4 filtered concentrated

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of α,ε-dicarbobenzoxy-L-lysine (4) (96 mmol, 39.69 g), toluene (310 ml) and triethylamine (96 mmol, 9.70 g) at 0° C., was added, over a period of 15 minutes, iso-butyl chloroformate (109 mmol, 14.88 g), maintaining the temperature between -5° and 0° C. The resulting jelly-like reaction mixture was stirred for 30 minutes at 0° C. and then a slurry of L-phenylalanine benzyl ester, p-toluene sulphonate (1) (96 mmol, 40.99 g) in chloroform (470 ml) and triethylamine (96 mmol, 9.70 g) was added quickly in one portion and the clear solution was allowed to stir at ambient temperature overnight. The resulting jelly-like reaction mixture to stir at ambient temperature overnight

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

Procedure: N-(t-butoxycarbonyl)-L-aspartic acid 4-benzyl ester was coupled with 3-phenyl-L-alanine benzyl ester to give N-[3-[(benzyloxy)carbonyl]-N-(t-butoxycarbonyl)-L-alanyl]-3-phenyl-L-alanine benzyl ester, m.p. 93°-94° C.

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

Procedure: Boc-L-Pro-OH and L-Phe-OBn.Hcl were treated with BOP and NMM in DMF to give, after aqueous workup and flash chromatography, Boc-L-Pro-L-Phe-OBn. This product was then treated with TFA and anisole, and the mixture was evaporated. The residue was dissolved in Et2O and washed with saturated aqueuos NaHCO3 and saturated aqueous NaCl. The Et2O layer was dried over anhydrous MgSO4, filtered, and the solvent evaporated to give L-Pro-L-Phe-OBn. The residue was treated with CH3SO2Cl and Et3N in CH2Cl2 to give, after aqueous workup and flash chromatography, N-(CH3SO2)-L-Pro-L-Phe-OBn. This product was then treated with 10% Pd on C in THF, and the mixture was shaken under 50 psi H2. The mixture was filtered through Celite, and evaporated to give the title compound as a clear oil. to give the mixture was evaporated The residue was dissolved in Et2O washed with saturated aqueuos NaHCO3 and saturated aqueous NaCl The Et2O layer was dried over anhydrous MgSO4 filtered the solvent evaporated

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

Procedure: Boc-L-Pro-OH and L-Phe-OBn.Hcl were treated with BOP and NMM in DMF to give, after aqueous workup and flash chromatography, Boc-L-Pro-L-Phe-OBn. This product was then treated with TFA and anisole, and the mixture was evaporated. The residue was dissolved in Et2O and washed with saturated aqueuos NaHCO3 and saturated aqueous NaCl. The Et2O layer was dried over anhydrous MgSO4, filtered, and the solvent evaporated to give L-Pro-L-Phe-OBn. The residue was treated with CH3SO2Cl and Et3N in CH2Cl2 to give, after aqueous workup and flash chromatography, N-(CH3SO2)-L-Pro-L-Phe-OBn. This product was then treated with 10% Pd on C in THF, and the mixture was shaken under 50 psi H2. The mixture was filtered through Celite, and evaporated to give the title compound as a clear oil. to give the mixture was evaporated The residue was dissolved in Et2O washed with saturated aqueuos NaHCO3 and saturated aqueous NaCl The Et2O layer was dried over anhydrous MgSO4 filtered the solvent evaporated

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

Procedure: To a solution of L-Phenylalanine benzylester (1.8 g, 6.8 mmol) in 1,4-dioxane (10 mL) was added 1,3-propanesultone (708 mg, 6.5 mmol). The solution was stirred at reflux. After 1 hour, 20 mL of 1,4-dioxane was added to allow for good stiffing. The reaction was stirred at reflux for an additional 1 hour. It was cooled to room temperature. The solid was collected by filtration, washed with acetone (2×25 mL). The product was suspended 80% Acetone/EtOH. The suspension was stirred at reflux for 30 seconds. The solid was filtered and dried in the vacuum oven (50° C.) affording the title compound (1.14 g, 46%). 1H NMR (DMSO, 500 MHz) δ ppm 7.27 (m, 6H), 7.12 (m, 4H), 5.05 (dd, 2H, J=12.3 Hz), 4.49 (m, 1H). 3.29 (m, 1H), 3.00 (m, 1H), 2.98 (m, 1H), 2.61 (t, 2H, J=6.5 Hz), 1.97 (m, 2H). 13C (DMSO, 125 MHz) δ ppm 168.88, 135.21, 134.90, 130.00, 129.31, 129.07, 128.01, 67.98, 60.50, 49.77, 46.72, 35.87, 22.43. [α]D=+4.8° (c=0.00073 in water), ES-MS 378 (M+1). at reflux The reaction was stirred at reflux for an additional 1 hour The solid was collected by filtration washed with acetone (2×25 mL) The suspension was stirred at reflux for 30 seconds The solid was filtered dried in the vacuum oven (50° C.)

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

Procedure: To 200 mg (0.42 mmol) of 3-[hydroxy[2-phenyl-1-[[(phenylmethoxy)carbonyl]amino]ethyl]phosphinyl]-2-(phenylmethyl)propanoic acid, 178 mg (0.42 mmol) of phenylmethyl L-phenylalaninate in the form of the p-toluenesulphonic acid salt and 384 mg (0.87 mmol) of BOP in 0.8 ml of dimethylformamide is added, with stirring at a temperature in the region of 20° C., 0.7 ml of diisopropylethylamine. After reaction for 30 minutes at this temperature, the dimethylformamide is evaporated off under reduced pressure and 12 ml of 1N hydrochloric acid are added to the oily residue obtained. The precipitate is filtered off, washed with water and dried. 210 mg of product are recovered (yield=70.3%). After reaction for 30 minutes at this temperature the dimethylformamide is evaporated off under reduced pressure and 12 ml of 1N hydrochloric acid are added to the oily residue obtained The precipitate is filtered off washed with water dried 210 mg of product are recovered (yield=70.3%)

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

Procedure: Referring to FIG. 45, DIPEA (270 μL, 1.6 mmol, 2.5 eq) was added to a mixture of acid (S)-4-methyl-2-((S)-2-(2-morpholinoacetamido)-4-phenyl-N-((pivaloyloxy)methyl)butanamido)pentanoic acid (345 mg, 0.64 mmol), H-Phe-OBn (283 mg, 0.97 mmol, 1.5 eq) and HATU (370 mg, 0.97 mmol, 1.5 eq) in CH2Cl2 (10 mL) and the mixture was stirred for four hours at RT. The mixture was poured into water and extracted twice with CH2Cl2. The combined organic extracts were dried over Na2SO4 and concentrated in vacuo. The residue was purified by chromatography (SiO2, 0-80% EtOAc in heptanes) and product (330 mg, 67%) was isolated as a colorless oil. extracted twice with CH2Cl2 The combined organic extracts were dried over Na2SO4 concentrated in vacuo The residue was purified by chromatography (SiO2, 0-80% EtOAc in heptanes)

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

Procedure: To N-(toluene-4-sulfonyl)-L-alanine (2.0 mmoles) in DMF (10 mL) was added BOP (2.1 mmoles) and N-methylmorpholine (4.0 mmoles) and the reaction stirred at room temperature for 45 minutes. L-Phenylalanine benzyl ester (2.0 mmoles) was added and the reaction stirred for 16 hours at room temperature. The reaction mixture was extracted with water (100 mL) and diethyl ether (3×50 mL) The combined organic layers were successively washed with 0.2 N HCl (2×50 mL), sat. NaHCO3 (50 mL), and sat. NaCl (50 mL). The organic layer was dried over MgSO4, filtered, and concentrated to yield a colorless oil (387 mg, 40%). The crude product was purified by silica gel chromatography (50% EtOAc /Hexane, Rf=0.61). The title compound was crystalized from CHCl3/Hexane to yield a white solid, mp=109-110° C. the reaction stirred for 16 hours at room temperature The reaction mixture was extracted with water (100 mL) and diethyl ether (3×50 mL) The combined organic layers were successively washed with 0.2 N HCl (2×50 mL), sat. NaHCO3 (50 mL), and sat. NaCl (50 mL) The organic layer was dried over MgSO4 filtered concentrated

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of α,ε-dicarbobenzoxy-L-lysine (4) (96 mmol, 39.69 g), toluene (310 ml) and triethylamine (96 mmol, 9.70 g) at 0° C., was added, over a period of 15 minutes, iso-butyl chloroformate (109 mmol, 14.88 g), maintaining the temperature between -5° and 0° C. The resulting jelly-like reaction mixture was stirred for 30 minutes at 0° C. and then a slurry of L-phenylalanine benzyl ester, p-toluene sulphonate (1) (96 mmol, 40.99 g) in chloroform (470 ml) and triethylamine (96 mmol, 9.70 g) was added quickly in one portion and the clear solution was allowed to stir at ambient temperature overnight. The resulting jelly-like reaction mixture to stir at ambient temperature overnight

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of α,ε-dicarbobenzoxy-L-lysine (4) (96 mmol, 39.69 g), toluene (310 ml) and triethylamine (96 mmol, 9.70 g) at 0° C., was added, over a period of 15 minutes, iso-butyl chloroformate (109 mmol, 14.88 g), maintaining the temperature between -5° and 0° C. The resulting jelly-like reaction mixture was stirred for 30 minutes at 0° C. and then a slurry of L-phenylalanine benzyl ester, p-toluene sulphonate (1) (96 mmol, 40.99 g) in chloroform (470 ml) and triethylamine (96 mmol, 9.70 g) was added quickly in one portion and the clear solution was allowed to stir at ambient temperature overnight. The resulting jelly-like reaction mixture to stir at ambient temperature overnight

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

Procedure: N-(t-butoxycarbonyl)-L-aspartic acid 4-benzyl ester was coupled with 3-phenyl-L-alanine benzyl ester to give N-[3-[(benzyloxy)carbonyl]-N-(t-butoxycarbonyl)-L-alanyl]-3-phenyl-L-alanine benzyl ester, m.p. 93°-94° C.