has role metabolite porphyrins tetrapyrrole fundamental parent porphyrin Porphyrin beilstein:622855 gmelin:205920 porphyrin CHEBI:8337 beilstein:36080 cas:101-60-0 kegg.compound:C05113 hmdb:HMDB0000839 21H,23H-Porphin porphyrin 21H,23H-porphine beilstein:1222991 reaxys:1160988 porphine pubmed:22735334 wikipedia.en:Porphyrin