phytochlorin

Noun

 * 1)  A tricarboxylic acid (17~{S},18~{S})-18-(2-carboxyethyl)-20-(carboxymethyl)-12-ethenyl-7-ethyl-3,8,13,17-tetramethyl-17,18,22,23-tetrahydroporphyrin-2-carboxylic acid derived from porphyrin