B-(1′,2,2′,3,5,6-Hexahydro-2′-oxospiro[4H-pyran-4,3′-[3H]pyrrolo[3,2-b]pyridin]-6′-yl)boronic acid

(2'-Oxo-1',2'-dihydrospiro[oxane-4,3'-pyrrolo[3,2-b]pyridin]-6'-yl)boronic acid