Question

What is the chemical name for vitamin B3?

Answer 1

Hint: Vitamin B3 is often a part of daily multivitamin diet but most people get enough niacin/ vitamin B3 from the food they eat. It lowers LDL cholesterol and increases HDL cholesterol, prevents heart diseases, treats type I diabetes, boosts brain function, improves skin functions, etc.

Complete answer:
Vitamin B3 can be manufactured by plants and animals both from amino acid tryptophan.
It's chemical name is niacin and IUPAC name is pyridine-3 carboxylic acid. We can get it from our regular diets from a variety of whole and processed foods, with highest content in fortified packaged foods, meats , poultry, red fish, nuts , legumes, seeds , etc.
It is used as a dietary supplement to treat pellagra (caused by niacin deficiency). It's symptoms are mouth and skin lesions, anemia, headache, tiredness, etc. Many countries mandate it's addition with wheat flour and other cereal grains to compensate it's deficiency.
It's chemical formula is $C_6H_5NO_2$. It is a benzene derivative compound. It appears as somewhat white or translucent crystals.
The amide derivative nicotinamide is a component of the coenzyme NAD or $NADP^+$. Although niacin and nicotinamide are identical in their vitamin activity, nicotinamide does not have the same pharmacological, lipid modifying effects or side effects as niacin i.e when niacin takes on the amide group, it does not reduce cholesterol.
The liver can synthesize niacin from essential amino acid tryptophan, requiring 60 mg of tryptophan to make 1 mg of niacin. Riboflavin, vitamin B6 and iron are required in some of the reactions involved in the conversion of tryptophan to NAD.

Note:
Niacin was first described by chemist Hugo Seidel in 1873 in his studies of nicotine. For the first time nicotine was extracted by Casimir Funk. Niacin is referred to as vitamin B3 as it was the third of the vitamin to be discovered.