The molecule is an organic cation that is porphyrin bearing four 1-methylpyridinium-4-yl groups at the 5-, 10-, 15- and 20-positions. It has a role as a photosensitizing agent, an angiogenesis inhibitor, an antineoplastic agent and an EC 2.7.7.49 (RNA-directed DNA polymerase) inhibitor. It derives from a hydride of a porphyrin.
5,10,15,20-tetrakis(1-methylpyridin-1-ium-4-yl)-21,23-dihydroporphyrin