Complete spectroscopic structural characterization of novobiocin, isonovobiocin, decarbamylnovobiocin, 2 ''-(O-carbamyl)novobiocin, and novobiocin-2 '',3 ''-carbonate

The rigorous structural characterization of novobiocin, is reported using m ass spectrometric, infrared and nmr spectroscopic analysis. Complete nmr as signments are reported. Previous reports in the literature had left some qu aternary carbon resonances unassigned. Isonovobiocin and decarbamylnovobioc in, although known in the literature for a number of years, have never been completely characterized. Mass spectrometric fragmentation pathways and co mplete H-1 and C-13 nmr assignments are reported for these congeners for th e first time. The mass spectral fragmentation pathway and nmr assignments a re also reported for 2 "-(O-carbamyl)novobiocin although the nmr assignment s at lower field were reported previously. The structural characterization of novobiocin-2 ",3 "-carbonate observed in the Test Assay procedure used f or Novobiocin is reported for the first time.