C-2491;4-(4-BOC-PIPERAZIN-1-YLSULFONYL)PHENYLBORONIC ACID PINACOL ESTER;2-{4-[((4-tert-butoxycarbonyl)piperazin-1-yl)sulfonyl]phenyl}-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane;tert-butyl 4-((4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)sulfonyl)pi