Melting point: 236-239℃(lit.)
Boiling point: 292.5 ℃
Density: 1.473 g/cm³
Refractive index: 1.5423 (estimate)
Flash point: 193°C
Storage conditions: 2-8℃
Niacin belongs to the vitamin B family, also known as niacin, vitamin B3, and anti-dermatosis factor. Its molecular formula is C6H5NO2 and its chemical name is pyridine-3-carboxylic acid. It has good thermal stability and can be sublimated. The industry often uses sublimation to purify niacin. . Niacin is white crystal or white crystalline powder in appearance. It is soluble in water. It is mainly found in internal organs and muscle tissues of animals. There are also traces in fruits and egg yolks. It is one of the 13 essential vitamins for the human body.
Niacin is used as a medicine to prevent and treat skin diseases and similar vitamin deficiencies. It has the effect of expanding blood vessels and is used to treat peripheral nerve spasms, arteriosclerosis and other diseases. Niacin can also be used as a pharmaceutical intermediate to synthesize a variety of amides and ester drugs with important medical uses. For example, niacinamide can be used to treat gastrointestinal diseases. Niacin hydroxymethylamine is a good medicine for protecting liver, choleretic and antibacterial. Nicotinylbenzamide, as a highly effective snail-killing drug, can be used to prevent and treat schistosomiasis; niacin and tromethamine can be synthesized to treat circulatory disorders, vitamin B deficiency, glossitis, hypertension and other diseases; niacin Nicosamide synthesized with diethylamine is a central nervous system stimulant used to treat central nervous system respiratory and circulatory system failure; inositol nicotinate and metronidazole produced by the reaction of niacin with alcohol are used to treat hyperlipidemia Drugs for disease, coronary heart disease, migraine, peripheral vascular dysfunction, etc.
It can also be used as a feed additive to increase the utilization rate of feed protein, increase milk production of dairy cows and the production and quality of poultry meat such as fish, chickens, ducks, cattle and sheep. In addition, niacin also plays an irreplaceable role in the fields of luminescent materials, dyes, and electroplating industries.
Initially, nicotinic acid was synthesized by oxidizing nicotine in industrialization. Later, quinoline, 2-methyl-5-ethylpyridine and 3-methylpyridine were mostly used as raw materials to synthesize nicotinic acid by chemical or electrochemical oxidation. From the classification of synthesis methods, it is generally divided into reagent oxidation methods using nitric acid, potassium permanganate, etc. as oxidants, ammonia oxidation methods using ammonia and air as oxidants, direct air oxidation methods, electrolytic oxidation methods, biotransformation methods, and pyridine hydroxyl etc. From the classification of the main raw materials, there are nicotine, 6-hydroxyquinoline, naphthalene, pyridine, 3-pyridinecarboxaldehyde, 3-methylpyridine, 2-methyl-5-ethylpyridine, and 3-methylpyridine is currently widely used. The pyridine route.