Nicotinamide, also known as niacinamide and nicotinic acid amide, is the amide of nicotinic acid (vitamin B3 / niacin). Nicotinamide is a water-soluble vitamin and is part of the vitamin B group. Nicotinic acid, also known as niacin, is converted to nicotinamide in vivo, and though the two are identical in their vitamin functions, nicotinamide does not have the same pharmacologic and toxic effects of niacin, which occur incidental to niacin's conversion.

Orotic acid is a heterocyclic compound and an acid; it is also known as pyrimidinecarboxylic acid. It was once believed to be part of the vitamin B complex and was called vitamin B13, but it is now known that it is not a vitamin but is instead manufactured in the body by intestinal flora.

Pyridoxal is one of the three natural forms of vitamin B6, along with pyridoxamine and pyridoxine (also called "pyridoxol"). All of these forms are converted in the human body into a single biologically active form, pyridoxal 5-phosphate. All three forms of vitamin B₆ are heterocyclic organic compounds.

Pangamic acid is an ester derived from gluconic acid and dimethylglycine.[1] It was first isolated by Ernst T. Krebs from apricot kernels,[2] and has since been identified in some foods such as pulses[3] and rice bran.