To a solution of compound 324 (0.10 g, 0.25 mmol) in dioxane (2 mL) was (E)-tert-butyldimethyl(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)but-3-enyloxy)silane (0.115 g, 0.50 mmol), followed by K2CO3 (0.069 g, 0.50 mmol) and water (0.40 mL). The resulting mixture was degassed with nitrogen and Pd(PPh3)4 (0.023 g, 0.02 mmol) was added. The mixture was heated in microwave reactor at 160° C. for 20 min. The mixture was diluted with EtOAc, and filtered through celite. The organic layer was concentrated, washed with water, dried over anhydrous Na2SO4 and concentrated again. The residue was purified using PL-Thiol MP SPE tube to provide compound 47A (0.126 g, 99%). LCMS (+ESI) m/z 506.4 [M+H]+.
