Summary Summary. Acute intermittent porphyria (AIP) is one of the liver (hepatic) porphyrias. AIP is caused by low levels of porphobilinogen deaminase (PBGD), an enzyme also often called hydroxymethylbilane synthase.
Pyridine-N-oxide is the heterocyclic compound with the formula C 5 H 5 NO. This colourless, hygroscopic solid is the product of the oxidation of pyridine. It was originally prepared using peracids as the oxidising agent. The molecule is planar.yridine-N-oxide is the heterocyclic compound with the formula C 5 H 5 NO. This colourless, hygroscopic solid is the product of the oxidation of pyridine. It was originally prepared using peracids as the oxidising agent. The molecule is planar.
The different substituents (e.g., the benzene ring in polystyrene, the chlorine atom in PVC, etc.) added to the linear polymer backbone have a profound effect on the physical properties of these materials, which is why polyethylene is a flexible polymer whereas PMMA and PVC are rather stiff. 2.