Tetramethoxydibenzoquinolizinium salts. Preparation and antileukemic activity of some positional and structural isomers of coralyne.

Some positional and structural isomers of coralyne were prepared and evaluated in the P388 lymphocytic leukemia system for their inhibitory activity. The levels of antileukemic activity of coralyne, neocoralyne, isocoralyne, and stracoralyne were comparable, thus implying that two sets of the N-O-O triangular pharmacophore in a condensed isoquinoline molecule are preferable and the angle between these two sets has little influence on antileukemic activity. The importance of the environment around the C5-C6 region of the dibenzo[a,g]quinolizine ring to antileukemic activity was demonstrated by the activity differences between coralyne and allocoralyne.