Pyrithione is the common name of an organosulfur compound with molecular formula C5H5NOS, chosen as an abbreviation of pyridinethione, and found in the Persian shallot.

[1] It is used to prepare zinc pyrithione,[9][10] which is used primarily to treat dandruff and seborrhoeic dermatitis in medicated shampoos,[11][12] though is also an anti-fouling agent in paints.

Pyrithione is found as a natural product in the Allium stipitatum plant, an Asian species of onion, also known as the Persian shallot.

[21] However, as apoptosis only occurs in higher organisms, this mechanism isn't relevant to the antifungal and bacteric idal properties of pyrithione.

Pyrithione exists as a pair of prototropes, a form of tautomerism whereby the rapid interconversion of constitutional isomers involves the shift of a single proton, in this case between the sulfur and oxygen atoms (shown in the infobox above).

In the solid state, it forms a dimer in which each zinc centre adopts a trigonal bipyramidal geometry with two of the anions acting as bridging ligands coordinated through the oxygen atoms in the axial positions.

[31][32] It can be used as an antibacterial agent against Staphylococcus and Streptococcus infections for conditions such as athlete's foot, eczema, psoriasis, and ringworm.