Synthesis, chromatographic behaviour and mass spectral fragmentation pattern of some 2-substituted 4/5-nitrobenzimidazoles are described. The mass spectral data of these benzimidazoles, in conjunction with mass-spectral data obtained for corresponding 2-substituted benzimidazoles having no nitrosubstituent in benzene ring show that fragments at m/e 103, 91, 90, 64 and 63 are diagnostic for benzimidazole nucleus.


M AMJAD ,FARZANA LATIF ,MASHOODA HASAN ,NAEEMA KHAN ,