Pyridoxal is a pyridinecarbaldehyde that is pyridine-4-carbaldehyde bearing methyl, hydroxy and hydroxymethyl substituents at positions 2, 3 and 5 respectively. The 4-carboxyaldehyde form of vitamin B6, it is converted into pyridoxal phosphate, a coenzyme for the synthesis of amino acids, neurotransmitters, sphingolipids and aminolevulinic acid. It has a role as a cofactor, a mouse metabolite, a Saccharomyces cerevisiae metabolite, an Escherichia coli metabolite and a human metabolite. It is a member of methylpyridines, a vitamin B6, a monohydroxypyridine, a pyridinecarbaldehyde and a hydroxymethylpyridine. It is a conjugate base of a pyridoxal(1+).
