2-Bromopyridine-5-boronic acid pinacol ester2-Bromo-5-pyridylboronic acid pinacol ester2-溴吡啶-5-硼酸频哪酯酯2-Bromopyridine-5-boronic acid pinacol ester2-Bromo-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine2-Bromo-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine