(4S)-4-benzyl-1,3-thiazolidin-2-one

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

Procedure: To a solution of the compound obtained from step c above (2.1 g) in dichloromethane (25 mL) cooled to 0° C., 4-dimethylaminopridine (0.334 g) and triethylamine (5.7 mL) were added. After stirring the reaction mixture for 10 minutes, 1-(3-dimethylaminopropyl)-3-ethylcarbodimide hydrochloride (3.9 g) and 4-(4-oxo-1,2,3-benzotriazin-3(4H)-yl)butanoic acid (3 g) were added, and the reaction mixture was stirred at room temperature for 14 hours. Dichloromethane and water were added to the reaction mixture. The organic layer was separated, washed with water and brine solution, and dried over anhydrous sodium sulphate. The solvent was evaporated under reduced pressure to obtain a residue which was purified by column chromatography over silica gel using 25% ethyl acetate in hexane as eluant to afford the title compound (4.4 g). Mass (m/z): 409.16 the reaction mixture was stirred at room temperature for 14 hours The organic layer was separated washed with water and brine solution dried over anhydrous sodium sulphate The solvent was evaporated under reduced pressure to obtain a residue which was purified by column chromatography over silica gel using 25% ethyl acetate in hexane as eluant

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

Procedure: To a solution of (4S)-4-benzyl-1,3-thiazolidine-2-thione (38 g) in dichloromethane (350 mL) cooled to 0° C., propylene oxide (12.7 mL) and trifluoroacetic acid (14 mL) were added. After stirring the reaction mixture for 2 hours, the solvents were evaporated under reduced pressure to obtain a residue which was purified by column chromatography over silica gel using 20% ethyl acetate in hexane as eluant to afford the title compound (0.9 g). the solvents were evaporated under reduced pressure to obtain a residue which was purified by column chromatography over silica gel using 20% ethyl acetate in hexane as eluant

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

Procedure: To a solution of the compound obtained from step c above (2.1 g) in dichloromethane (25 mL) cooled to 0° C., 4-dimethylaminopridine (0.334 g) and triethylamine (5.7 mL) were added. After stirring the reaction mixture for 10 minutes, 1-(3-dimethylaminopropyl)-3-ethylcarbodimide hydrochloride (3.9 g) and 4-(4-oxo-1,2,3-benzotriazin-3(4H)-yl)butanoic acid (3 g) were added, and the reaction mixture was stirred at room temperature for 14 hours. Dichloromethane and water were added to the reaction mixture. The organic layer was separated, washed with water and brine solution, and dried over anhydrous sodium sulphate. The solvent was evaporated under reduced pressure to obtain a residue which was purified by column chromatography over silica gel using 25% ethyl acetate in hexane as eluant to afford the title compound (4.4 g). Mass (m/z): 409.16 the reaction mixture was stirred at room temperature for 14 hours The organic layer was separated washed with water and brine solution dried over anhydrous sodium sulphate The solvent was evaporated under reduced pressure to obtain a residue which was purified by column chromatography over silica gel using 25% ethyl acetate in hexane as eluant

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

Procedure: To a solution of (4S)-4-benzyl-1,3-thiazolidine-2-thione (38 g) in dichloromethane (350 mL) cooled to 0° C., propylene oxide (12.7 mL) and trifluoroacetic acid (14 mL) were added. After stirring the reaction mixture for 2 hours, the solvents were evaporated under reduced pressure to obtain a residue which was purified by column chromatography over silica gel using 20% ethyl acetate in hexane as eluant to afford the title compound (0.9 g). the solvents were evaporated under reduced pressure to obtain a residue which was purified by column chromatography over silica gel using 20% ethyl acetate in hexane as eluant

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

Procedure: To a solution (4S)-4-benzyl-1,3-thiazolidine-2-thione (38 g) in dichloromethane (350 mL), cooled to 0° C. was added propylene oxide (12.7 mL) and trifluoroacetic acid (14 mL). After stirring the reaction mixture for 2 hours, the solvents were evaporated under reduced pressure to obtain a residue which was purified by column chromatography over silica gel using 20% ethylacetate in hexane as eluant to afford the title compound (0.9 g). Mass (m/z): 194.18 the solvents were evaporated under reduced pressure to obtain a residue which was purified by column chromatography over silica gel using 20% ethylacetate in hexane as eluant

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

Procedure: To a solution of the compound obtained from step c above (2.1 g) in dichloromethane (25 mL) cooled to 0° C., 4-dimethylaminopridine (0.334 g) and triethylamine (5.7 mL) were added. After stirring the reaction mixture for 10 minutes, 1-β-dimethylaminopropyl)-3-ethylcarbodimide hydrochloride (3.9 g) and 4-(4-oxo-1,2,3-benzotriazin-3(4H)-yl)butanoic acid (3 g) were added, and the reaction mixture was stirred at room temperature for 14 hours. Dichloromethane and water were added to the reaction mixture. The organic layer was separated, washed with water and brine solution, and dried over anhydrous sodium sulphate. The solvent was evaporated under reduced pressure to obtain a residue which was purified by column chromatography over silica gel using 25% ethyl acetate in hexane as eluant to afford the title compound (4.4 g). Mass (m/z): 409.16 the reaction mixture was stirred at room temperature for 14 hours The organic layer was separated washed with water and brine solution dried over anhydrous sodium sulphate The solvent was evaporated under reduced pressure to obtain a residue which was purified by column chromatography over silica gel using 25% ethyl acetate in hexane as eluant

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

Procedure: To a solution of (4S)-4-benzyl-1,3-thiazolidine-2-thione (38 g) in dichloromethane (350 mL) cooled to 0° C., propylene oxide (12.7 mL) and trifluoroacetic acid (14 mL) were added. After stirring the reaction mixture for 2 hours, the solvents were evaporated under reduced pressure to obtain a residue which was purified by column chromatography over silica gel using 20% ethyl acetate in hexane as eluant to afford the title compound (0.9 g). Mass (m/z): 194.18 the solvents were evaporated under reduced pressure to obtain a residue which was purified by column chromatography over silica gel using 20% ethyl acetate in hexane as eluant