A new cationic monoazaporphyrin, zinc 2-aza-8 12,13,17-tetraethyl-2,3,7,18-
tetramethylporphyrinium iodide 3 was synthesized. Photodynamic activity of
3 in degradation of 2',3'-isopropylideneguanosine 4 was compared with 2-aza
-8,12,13,17-tetraethyl-3,7,18-trimethylporphyrin 1, zinc 2-aza-8,12,13,17-t
etraethyl-3,7,18-trimethylporphyrin 2, and hematoporphyrin 5. The quarterna
ry ammonium 3 showed a remarkable increase of photodynamic activity compare
d with 5, although no appreciable difference in the activity was observed b
etween 1 and 5. (C) 2001 Elsevier Science Ltd. All rights reserved.