Synthesis of novel laterally-bridged pyropheophorbide a dimers

Abstract

Condensation of 13²-oxopyropheophorbide a with benzene-1,2,4,5-tetramine produced a bis-quinoxaline-bridged symmetrical chlorin dimer and an unsymmetrical benzimidazole/pyrazine bridged analog. Spectroscopic data of the novel conjugated dimers show a significant perturbation of the extended bis-chlorin π-system in a coplanar arrangement.

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