Biotin, also known as 　D-biotin,vitamin H or coenzyme R, is a water-soluble B-vitamin(vitamin B₇).

It is composed of a ureido(tetrahydroimidizalone) ring fused with a tetrahydrothiophenering. A valeric acidsubstituent is attached to one of the carbon atoms of the tetrahydrothiophene ring. Biotin is a coenzymefor carboxylase enzymes, involved in the synthesis of fatty acids, isoleucine, and valine, and in gluconeogenesis.

IUPAC name:

5-[(3aS,4S,6aR)-2-oxohexahydro-1H-thieno[3,4-d]imidazol-4-yl]pentanoic acid

Other names:

D-biotin,Vitamin B₇; Vitamin H; Coenzyme R; Biopeiderm

Identifiers
CAS number	58-85-5 Y
PubChem	171548
ChemSpider	149962 Y
UNII	6SO6U10H04 Y
DrugBank	DB00121
KEGG	D00029 Y
ChEBI	CHEBI:15956 Y
ChEMBL	CHEMBL857 Y
ATC code	A11HA05