[(3S)-2,5-dioxooxolan-3-yl] acetate

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To 3-fluoro-4-(5-(1-phenylcyclopropyl)thiazolo[5,4-b]pyridin-2-yl)benzenamine (70 mg, 0.194 mmol) and (S)-(−)-2-acetoxysuccinic anhydride (34 mg, 213 μmol) was added benzene (1.9 mL) and acetic acid (55 μl, 0.968 mmol) before it was stirred at 80° C. for 1 h. The reaction mixture was concentrated before the regioisomers were separated via SFC (Column: Chiralpak IC, Mobile Phase: liquid CO2/40% MeOH) to give (2S)-2-acetoxy-4-(3-fluoro-4-(5-(1-phenylcyclopropyl)-thiazolo[5,4-b]pyridin-2-yl)phenylamino)-4-oxobutanoic acid. MS (ESI) m/z: Calculated: 519.1; Observed: 520.1 (M++H). The reaction mixture was concentrated before the regioisomers were separated via SFC (Column: Chiralpak IC, Mobile Phase: liquid CO2/40% MeOH)