Vitamin B3 (
) is also known as pyridine-3-carboxylic acid
, or nicotinic acid
. The name in fact comes from ni
id + vitamin
There are several derivative compounds e.g.
- the amide
of nicotinic acid (also known as niacinamide).
These can act as a precursor to nicotinamide adenine dinucleotide and its phosphate derivative (often abbreviated as NAD+
/NADH and NADP+
/NADPH), which function as hydrogen and electron acceptors in respiration and photosynthesis.
Dietary deficiency causes pellagra:
cracked, scaly skin, dementia, and diarrhea.
At different (higher) doses, a number of pharmacological effects have been ascribed to niacin (but not the amide): reduction of high cholesterol, atherosclerosis, cataracts.