Substituent control in the diastereoselectivity of dipolar cycloadditions of nitrones and their Zn(II) complexes with N-arylmaleimides

Antibacterial activity, quantitative structure-activity relationship and diastereoselective synthesis of isoxazolidine derivatives via 1,3-dipolar cycloaddition of d-glucose derived nitrone with olefin

The diastereoselectivity of the intermolecular 1,3-dipolar cycloaddition reaction of d-glucose-derived nitrones with both cyclic and acyclic dipolarophiles were studied. The reaction of nitrone with acyclic dipolarophiles resulted in the formation of the endo adduct exclusively whereas with cyclic dipolarophiles endo adduct was obtained as the major product. Antibacterial activity was evaluated for these eighteen isoxazolidine derivatives against Staphylococcus aureus NCIM5021, Escherichia coli NCIM 2931 and Pseudomonas aeruginosa NCIM 5029 by twofold dilution technique using resazurin as the indicator dye. Quantitative structureactivity relationships were developed with fourteen and the model was validated with four data. Electronic and spatial descriptors were the major contributors in all the three quantitative structureactivity relationship equations and the statistical parameters r(2), r(2)(adj) , F-ratio and q(2) were found to be satisfactory.