In the CNS, the enzyme needed for the synthesis of nitric oxide, nitric oxide synthase (NOS), is present in discrete populations of neurons, but it is not present in glia. Three isoforms of NOS have been cloned; isoform I (nNOS or cNOS) is found in neurons and epithelial cells, isoform II (iNOS) is induced by cytokines and is found in macrophages and smooth muscle cells, and isoform III (eNOS) is found in endothelial cells lining blood vessels (Table 8-2). All three isoforms require tetrahydrobiopterin as a cofac-tor and nicotinamide adenine dinucleotide phosphate (NADPH) as a coenzyme. Isoforms I and III of NOS are activated by the influx of extracellular calcium into the cell. Isoform II (iNOS), the inducible form of NOS, is activated by cytokines. The steps involved in the activation of constitutive forms of NOS (cNOS and eNOS) are as follows (Fig. 8-16).
The first step is a Sonogashira coupling from 3-bromo-2-chloropyridine or 2-bromo-3-chloropyridine with several (hetero)arylalkynes to obtain the corresponding 2- or 3-chloro(hetero)arylethynylpyridines.
4-Chloropyridine N-oxide 98% | Sigma-Aldrich
Chemical property liquid
Use Intermediate of antiseptic
Use used for medicine, insecticide and organic synthesis
Categories poisonous substance
Toxicity grading high grade
Acute Toxicity oral-rat LCL0: 100 PPM/4h; oral-mouse LD50: 110 mg/kg
Flammability and Hazard Properties Flammable; cause poisonous nitric oxide after burned
Storage Property storehouse: ventilate, low temperature, dry; transported separately with food.
Fire-extinguishing agent dry powder, foam, sandy soil