Some of these amphiphiles are phenyl, naphthalene, phenanthrene, pyrene and porphyrin systems. Or the formation of the pyrene "dibenzo-(a.1)-pyrene" from the anthracene "1-phenylbenz(a)anthracene" (66% yield). Experiments in pig show that urinary 1-hydroxypyrene is a metabolite of pyrene, when given orally. Experiments in pigs show that urinary 1-hydroxypyrene is a metabolite of pyrene, when given orally. It is a structural isomer of the alternant PAH pyrene. As a peri-fused PAH, pyrene is much more resonance-stabilized than its five-member-ring containing isomer fluoranthene. Naphthalenetetracarboxylic dianhydride is prepared by oxidation of pyrene. For example, pyrene was shown to form semiconducting charge-transfer complex salts with halogens. The synthesis starts using a Wittig reaction of pyrene carboxaldehyde. It is not as thermodynamically stable as pyrene. It has been used as a solvent probe, similar to pyrene. Minimax was purchased by The Pyrene Company Limited in 1955. Cycnus was the son of Ares by Pelopia or Pyrene. Fire fighting equipment was provided by The Pyrene Company Limited. Bebryx was also the father of Pyrene.