Synthesis of 2″-acylamido derivatives of 2″-amino-5,2″-dideoxy-5-epi-5-fluorodibekacin and a study on the structures of 5-fluorinated dibekacin analogs by 13C NMR

Several 2″-amino-2″-deoxy and 2″-acylamido-2″-deoxy derivatives (15–21) of 5-deoxy-5-epi-5-fluorodibekacin have been prepared, introducing the 2″-NH2 group via oxidation-methoxyimination-reduction processes. The C-4 and C-6 chemical shifts in the 13C NMR spectra of several 5-fluorinated kanamycin analogs have been studied, and the difference in shifts was explained on the basis of F-5-O-4 and F-5-O-6 distances estimated by MOPAC93/PM3 calculations on related model compounds.