pyrroporphyrin

\\|pi(ˌ)rō+\ noun

Etymology: International Scientific Vocabulary pyrrh- + porphyrin

: a dark red crystalline pigment C₃₂H₃₆N₄O₂ with a violet metallic luster that is the lower homologue of phylloporphyrin and that differs from most porphyrins in being a hepta-substituted derivative of porphin rather than an octa-substituted one