n. (context organic compound English) A ring or four pyrrole rings linked by methine groups; it is the structure at the centre of hemoglobin, chlorophyll and other porphyrins
Porphin, sometimes spelled porphine, is the parent chemical compound for types of biochemically significant compounds called porphyrins. The chemical formula of porphin is CHN. Porphin is an organic compound that is aromatic and heterocyclic since its chemical structure, shown at right, essentially consists of four pyrrole rings joined together by four methine (= C H—) groups to form a larger macrocycle ring. The compound itself is a solid.