3-(ethylamino)propanoic acid

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

Procedure: 3-Ethylaminopropionic acid (19.8 g) was reacted with 4-chloro-2-methylphenylisothiocyanate (20 g), triethylamine (20 g), and methylene chloride (250 mL) according to the procedure described in step 2 of Example 1 to give 12 g of 3-[3-(4-chloro-2-methylphenyl)-1-ethyl-thioureido]propionic acid. The product (12 g) was dissolved in acetone (245 mL). Conc. HCl (5 mL) was added and the mixture was heated at reflux for 18 hours. The reaction mixture was evaporated to dryness. The residue was dissolved in methylene chloride (100 mL), and washed with 1N NaOH. The organic phase was dried over anhydrous magnesium sulfate, then evaporated to dryness. The solid was recrystallized from ethanol. The title compound (8 g) was obtained as a white solid., m.p. 133°-136° C.

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

Procedure: A mixture of 3-ethylaminopropionic acid (19.8 g), 2,6-dimethylphenyl-isothiocyanate (16.3 g), triethylamine (20 g) and methylene chloride (200 mL) was heated at reflux for 3 hours. The cooled reaction mixture was extracted with 1N NaOH (150 mL). The aqueous layer was separated and acidified with 2N HCl. The solid formed was collected by filtration. Recrystallization from ethanol afforded the title compound (11 g) as a white solid, m.p. 115°-118° C. was heated at reflux for 3 hours The cooled reaction mixture was extracted with 1N NaOH (150 mL) The aqueous layer was separated The solid formed was collected by filtration Recrystallization from ethanol

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

Procedure: A mixture of 3-ethylaminopropionic acid (19.8 g), 2,6-dimethylphenyl-isothiocyanate (16.3 g), triethylamine (20 g) and methylene chloride (200 mL) was heated at reflux for 3 hours. The cooled reaction mixture was extracted with 1N NaOH (150 mL). The aqueous layer was separated and acidified with 2N HCl. The solid formed was collected by filtration. Recrystallization from ethanol afforded the title compound (11 g) as a white solid, m.p. 115°-118° C. was heated at reflux for 3 hours The cooled reaction mixture was extracted with 1N NaOH (150 mL) The aqueous layer was separated The solid formed was collected by filtration Recrystallization from ethanol

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

Procedure: A mixture of 3-ethylaminopropionic acid (19.8 g), 2,6-dimethylphenyl-isothiocyanate (16.3 g), triethylamine (20 g) and methylene chloride (200 mL) was heated at reflux for 3 hours. The cooled reaction mixture was extracted with 1N NaOH (150 mL). The aqueous layer was separated and acidified with 2N HCl. The solid formed was collected by filtration. Recrystallization from ethanol afforded the title compound (11 g) as a white solid, m.p. 115°-118° C. was heated at reflux for 3 hours The cooled reaction mixture was extracted with 1N NaOH (150 mL) The aqueous layer was separated The solid formed was collected by filtration Recrystallization from ethanol

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

Procedure: A suspension of ethyl β-alanine.HCl (2.81 g, 18.3 mmol) and 4-cyano-benzoyl chloride (3.03 g, 18.0 mmol) in DCM (30 mL) was stirred overnight at RT. The mixture was diluted with EtOAc, washed with aq. citric acid (3%), sat. aq. NaHCO3 and H2O. Drying (MgSO4) and evaporation of the solvent gave compound 2 (2.52 g, 56%). washed with aq. citric acid (3%), sat. aq. NaHCO3 and H2O Drying (MgSO4) and evaporation of the solvent