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

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

Procedure: 3-{2-[6-(Tetrahydro-pyran-2-yloxycarbamoyl)-hexylcarbamoyl]-1H-indol-5-yl}-propionic acid (0.357 g, 0.78 mmol) was dissolved in DCM/DMF (20 ml/20 ml). EDCl.HCl (0.163 mg, 0.86 mmol), triethylamine (0.24 ml, 1.7 mmol), HOBt (0.116 mg, 0.88 mmol) and L-phenylalanine cyclopentyl ester.TsOH salt (0.346 mg, 0.88 mmol) were added and the reaction mixture stirred for 16 h at room temperature under nitrogen. The solvent volume was reduced (˜10 ml), DCM was added and the organic layer washed with water (×3). The organic layer was dried (Na2SO4) and the solvent removed to give the required product (500 mg, 95% yield) which was used without further purification. LCMS purity 77%, m/z 675 [M++H]+ was added the organic layer washed with water (×3) The organic layer was dried (Na2SO4) the solvent removed

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

Procedure: 3-{2-[6-(Tetrahydro-pyran-2-yloxycarbamoyl)-hexylcarbamoyl]-1H-indol-5-yl}-propionic acid (0.357 g, 0.78 mmol) was dissolved in DCM/DMF (20 ml/20 ml). EDCl.HCl (0.163 mg, 0.86 mmol), triethylamine (0.24 ml, 1.7 mmol), HOBt (0.116 mg, 0.88 mmol) and L-phenylalanine cyclopentyl ester.TsOH salt (0.346 mg, 0.88 mmol) were added and the reaction mixture stirred for 16 h at room temperature under nitrogen. The solvent volume was reduced (˜10 ml), DCM was added and the organic layer washed with water (×3). The organic layer was dried (Na2SO4) and the solvent removed to give the required product (500 mg, 95% yield) which was used without further purification. LCMS purity 77%, m/z 675 [M++H]+ was added the organic layer washed with water (×3) The organic layer was dried (Na2SO4) the solvent removed

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

Procedure: 3-{2-[6-(Tetrahydro-pyran-2-yloxycarbamoyl)-hexylcarbamoyl]-1H-indol-5-yl}-propionic acid (0.357 g, 0.78 mmol) was dissolved in DCM/DMF (20 ml/20 ml). EDCl.HCl (0.163 mg, 0.86 mmol), triethylamine (0.24 ml, 1.7 mmol), HOBt (0.116 mg, 0.88 mmol) and L-phenylalanine cyclopentyl ester.TsOH salt (0.346 mg, 0.88 mmol) were added and the reaction mixture stirred for 16 h at room temperature under nitrogen. The solvent volume was reduced (˜10 ml), DCM was added and the organic layer washed with water (×3). The organic layer was dried (Na2SO4) and the solvent removed to give the required product (500 mg, 95% yield) which was used without further purification. LCMS purity 77%, m/z 675 [M++H]+ was added the organic layer washed with water (×3) The organic layer was dried (Na2SO4) the solvent removed

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

Procedure: 3-{2-[6-(Tetrahydro-pyran-2-yloxycarbamoyl)-hexylcarbamoyl]-1H-indol-5-yl}-propionic acid (0.357 g, 0.78 mmol) was dissolved in DCM/DMF (20 ml/20 ml). EDCl.HCl (0.163 mg, 0.86 mmol), triethylamine (0.24 ml, 1.7 mmol), HOBt (0.116 mg, 0.88 mmol) and L-phenylalanine cyclopentyl ester.TsOH salt (0.346 mg, 0.88 mmol) were added and the reaction mixture stirred for 16 h at room temperature under nitrogen. The solvent volume was reduced (˜10 ml), DCM was added and the organic layer washed with water (×3). The organic layer was dried (Na2SO4) and the solvent removed to give the required product (500 mg, 95% yield) which was used without further purification. LCMS purity 77%, m/z 675 [M++H]+ was added the organic layer washed with water (×3) The organic layer was dried (Na2SO4) the solvent removed

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

Procedure: Intermediate 6 (50 mg, 0.15 mmol) was added to a colourless solution of L-phenylalanine cyclopentyl ester (89 mg, 0.38 mmol) in MeOH (10 ml) at RT/N2 and stirred at RT for 1 h. AcOH glacial was added dropwise to adjust the pH to 6 followed by the NaCNBH3 (38 mg, 0.61 mmol). The resultant colourless solution was stirred at RT overnight and then carefully quenched with sat. NaHCO3 (20 ml) and extracted into CH2Cl2 (3×15 ml). The combined organic phases were washed with 2M HCl (2×20 ml), brine (20 ml), dried (Na2SO4), filtered and concentrated in vacuo giving a cream coloured solid. Purification by flash column chromatography (silica, gradient elution 40-100% EtOAc/heptane) gave the desired material, separable as two isomers, isomer 1 (Example 34) as a white solid (Yield=39 mg, 47%) LCMS purity 100%, m/z 546 [M+H]+, 1H NMR (400 MHz, CD3OD), δ: 1.40-2.05 (16H, m), 2.85-3.10 (3H, m), 3.60-3.70 (1H, m), 4.55-4.65 (1H, m), 5.10-5.20 (1H, m), 5.70 (1H, d), 7.15-7.40 (7H, m), 7.45-7.50 (1H, m), 7.50-7.60 (2H, m) and isomer 2 (Example 35) LCMS purity 97%, m/z 546 [M+H]+, 1H NMR (400 MHz, CD3OD), δ: 1.25-1.85 (12H, m), 1.95-2.20 (2H, m), 2.45-2.95 (4H, m), 3.00-3.10 (1H, m), 3.65-3.75 (1H, m), 4.55-4.65 (1H, m), 5.05-5.15 (1H, m), 5.65 (1H, d), 7.20-7.35 (7H, m), 7.40-7.50 (1H, m), 7.50-7.60 (2H, m) as a colourless film (Yield=15 mg, 18%). The resultant colourless solution was stirred at RT overnight carefully quenched with sat. NaHCO3 (20 ml) extracted into CH2Cl2 (3×15 ml) The combined organic phases were washed with 2M HCl (2×20 ml), brine (20 ml) dried (Na2SO4) filtered concentrated in vacuo giving a cream Purification by flash column chromatography (silica, gradient elution 40-100% EtOAc/heptane)

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

Procedure: 3-{2-[6-(Tetrahydro-pyran-2-yloxycarbamoyl)-hexylcarbamoyl]-1H-indol-5-yl}-propionic acid (0.357 g, 0.78 mmol) was dissolved in DCM/DMF (20 ml/20 ml). EDCl.HCl (0.163 mg, 0.86 mmol), triethylamine (0.24 ml, 1.7 mmol), HOBt (0.116 mg, 0.88 mmol) and L-phenylalanine cyclopentyl ester.TsOH salt (0.346 mg, 0.88 mmol) were added and the reaction mixture stirred for 16 h at room temperature under nitrogen. The solvent volume was reduced (˜10 ml), DCM was added and the organic layer washed with water (×3). The organic layer was dried (Na2SO4) and the solvent removed to give the required product (500 mg, 95% yield) which was used without further purification. LCMS purity 77%, m/z 675 [M++H]+ was added the organic layer washed with water (×3) The organic layer was dried (Na2SO4) the solvent removed