PYRIDINIUM BETAINES DERIVED FROM THIAZOLO AND IMIDAZOACRIDINONES

Four betaines derived from imidazo[4,5-a], imidazo[5,4-a] and thiazolo [5,4-a]acridine have been prepared in a six step procedure starting fr om 2-chlorobenzimidazoles and benzothiazoles. The H-1 and C-13 nmr has been used to characterize the compounds, particularly the orientation of the step leading to the formation of the acridinone ring. The uv-v isible spectra of one betaine (wave numbers v in cm-l) shows a Linear dependence with Reichardt's E-T parameter and a high sensitivity to so lvent effects.