This suggested that 7-membered rings are a limitation for benzoxaboroles, consistent with work by Hall and coworkers, where the formation of an 8-membered BOB was also found to be disfavoured. The utility of organoboron compounds, including BOBs, within pharmaceutical development is linked with their ability to act as dynamic covalent inhibitors, especially for targets with alcohol-based residues in the active site (e.g., serine proteases). The method developed above allows access to rare BOB frameworks, which have significant potential for exploration of underdeveloped dynamic covalent inhibitor chemical space. Accordingly, with access to these compounds enabled, we sought to establish how effectively these may bind to exemplar biomolecules by comparison of binding affinity to representative ribosebased biomolecules vs. known organoboron compounds (Scheme 4). Using the procedure developed by Hall and coworkers, the association constants of representative BOB 19 were compared to that of tavaborole (40) and PhB(OH)2 (41) with D-fructose (42) and guanosine (43) (Scheme 4b). We observed that the binding of 19 to 42 displayed a Ka value almost double that of 40 and 41. More strikingly, 19 showed significantly enhanced binding to 43, compared to either 40 or 41. Moreover, BOB 19 displayed a high coefficient, >2-fold greater than tavaborole 40, where binding to ribose is the known mode of action. These data emphasize the potential use of these BOB scaffolds as sensors of sugars and nucleosides. In summary, a method for the synthesis of rare benzoxaboroles has been developed via Rh-catalyzed chelationassisted [2+2+2]cycloaddition. Leveraging the chelating effect of a local alcohol to offset the steric impact on catalytic turnover, synthetically practical Rh catalyst loading may be used to generate complex BOBs in good to excellent yields. The reaction exhibits good functional group tolerance and limitations have been disclosed. The dataset has also suggested an intramolecular alcohol-assisted BMIDA hydrolysis. Finally, comparative binding affinities for the new BOB frameworks to ribose-derived biomolecules have suggested utility as warheads for the development of dynamic covalent inhibitors, with greater affinity than other organoboron derivatives.