N-[(1R,2R)-1-Amino-2,3-dihydro-1H-inden-2-yl]-2,3-dichloro-4H-thieno[3,2-b]pyrrole-5-carboxamide trifluoroacetic acid salt (Method 8, 240 mg, 0.5 mmol), formic acid (50 μL, 1.4 mmol), DIPEA (174 μL, 1.0 mmol) and HOBT (67 mg, 0.5 mmol) were dissolved in DCM (5 ml), stirred for 5 mins, EDCI (120 mg, 0.625 mmol) added and the reaction stirred for 1 hr. Formic acid (50 μL, 1.4 mmol) and EDCI (240 mg, 1.25 mmol) were added, the reaction stirred for 2 hours and the volatiles removed by evaporation under reduced pressure. The residue was dissolved in EtOAc (20 mL), washed with water (2×10 mL), brine (10 mL), dried (MgSO4) and the volatiles removed by evaporation under reduced pressure. The residue was purified by column chromatography (2:1 EtOAc:Hexane) to afford the title compound (175 mg, 89%) as a white foam.
