Nickel octa­ethyl­porphyrin

Other names: nickel (II) 2,3,7,8,12,13,17,18-octa­ethyl­porphine, Ni(OEP)

C₃₆H₄₄N₄Ni

26/50 common

The porphyrins are a class of aromatic macrocycles common in biological systems capable of binding metals in their central N4 "pocket". Their extensive π-conjugation produces highly vivid and characteristic optical absorptions, and even at low concentrations many porphyrin species display intense colors from magenta to indigo. Porphyrins (or closely related N4 macrocycles) can be found as biological cofactors in such ubiquitous biomolecules as hemoglobin (where they coordinate iron), chlorophyll (where they coordinate magnesium), and vitamin B₁₂ (where they coordinate cobalt).