The structure of nicotinamide consists of a
pyridine ring to which a
primary amide group is attached in the
meta position. It is an
amide of
nicotinic acid. : from
nicotinonitrile by reaction with
phosphorus pentoxide, and from
3-aminopyridine by reaction with a solution of
sodium hypobromite, prepared
in situ from
bromine and
sodium hydroxide. , contains the nicotinamide
moiety (highlighted in red)
Industrial production The hydrolysis of
nicotinonitrile is catalysed by the enzyme
nitrile hydratase from
Rhodococcus rhodochrous J1, producing 3500 tons per annum of nicotinamide for use in animal feed. The enzyme allows for a more selective synthesis as further hydrolysis of the amide to
nicotinic acid is avoided. Nicotinamide can also be made from nicotinic acid. According to ''
Ullmann's Encyclopedia of Industrial Chemistry'', worldwide 31,000 tons of nicotinamide were sold in 2014. If humans ingest nicotinamide, it will likely undergo a series of reactions that transform it into NAD, which can then undergo a transformation to form NADP+. This method of creation of NAD+ is called a
salvage pathway. However, the human body can produce NAD+ from the
amino acid tryptophan and niacin without ingestion of nicotinamide. NAD+ acts as an electron carrier that mediates the interconversion of energy between nutrients and the cell's energy currency,
adenosine triphosphate (ATP). In
oxidation-reduction reactions, the active part of the cofactor is the nicotinamide. In NAD+, the nitrogen in the aromatic nicotinamide ring is covalently bonded to adenine dinucleotide. The shared electrons of the other carbon atoms in the
aromatic ring stabilize the formal charge on the nitrogen. When a
hydride atom is added onto NAD+ to form NADH, the molecule loses its
aromaticity and therefore a good amount of stability. This higher-energy product later releases its energy by donating a hydride, and in the case of the
electron transport chain, it assists in forming
adenosine triphosphate. When one mole of NADH is
oxidized, it releases 158.2k
J of energy.
Biological role Nicotinamide occurs as a component of a variety of biological systems, including within the
vitamin B family and specifically the
vitamin B3 complex. It is also a critically important part of the structures of
NADH and NAD+, where the
N-substituted aromatic ring in the oxidised NAD+ form undergoes reduction with hydride attack to form NADH. The
NADPH/NADP+ structures have the same ring, and are involved in similar biochemical reactions. Nicotinamide can be
methylated in the
liver to biologically inactive
1-methylnicotinamide when there are sufficient
methyl donors. == Food sources ==