A vessel was charged with 6-bromo-1-methyl-1H-indazol-3-amine (191 mg, 0.846 mmol), bis-pinacolatodiboron (236 mg, 0.930 mmol), PdCl2(dppf).DCM (69 mg, 85 μmol), glacial KOAc (273 mg, 2.79 mmol), and dioxane (3.2 mL). The reaction was heated to 100° C. for 1 h. To this reaction was added (S)-ethyl 2-(2-bromo-7-(4-chlorophenyl)-5-methylbenzo[d]thiazol-6-yl)-2-tert-butoxyacetate (420 mg, 0.846 mmol), 2 M aq K2CO3 (800 μL), and Pd(PPh3)4 (98 mg, 85 mmol). The reaction was heated for another 1 h at 100° C. The reaction was diluted with water and extracted with EtOAc (3×). Combined organic layers were dried (Na2SO4), filtered, and concentrated. The residue was treated with benzene and purification by flash column chromatography on silica gel (hexanes/ethyl acetate eluent) gave the title compound in semi-pure form. The mixture was treated with DCM and purification by flash column chromatography on silica gel (DCM/MeOH eluent) giving the title compound. LCMS-ESI+: calc'd for C30H31ClN4O3S: 563.2, 565.2 (M+H+); Found: 563.3, 565.3 (M+H+).
