A Fourier transform-Raman and infrared vibrational study of delorazepam, fludiazepam, flurazepam, and tetrazepam.
Fourier transform-Raman and IR spectra of four compounds that are closely related to diazepam (Valium) have been recorded. The compounds, delorazepam, fludiazepam, flurazepam, and tetrazepam, are all 7-chloro-1,3-dihydro-[2H]-1,4-benzodiazepine -2-ones and differ from diazepam by the substituents at positions 1 and 5 of the diazepine ring. The spectra show characteristic features associated with both the diazepine ring and substituents. A strong line near 1610 cm-1 in the Raman spectra is assigned to the C = N stretch of the diazepine ring, and very strong IR absorption near 1690 cm-1 is attributed to the C = O stretching mode. Various IR and Raman vibrational features serve to characterize and differentiate these molecules. Evidence for intermolecular hydrogen bonding in one of the compounds (delorazepam) is presented.
Neville
G A
GA
Bureau of Drug Research, Health and Welfare Canada, Ottawa, Ontario.
Beckstead
H D
HD
Shurvell
H F
HF
D014151:Anti-Anxiety Agents / Q000032:analysis*; D001569:Benzodiazepines; D005583:Fourier Analysis; D006860:Hydrogen Bonding; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman
D014151:Anti-Anxiety Agents; D001569:Benzodiazepines