1,3-Butanediol

1,3-Butanediol is an organic compound with the formula CH3CH(OH)CH2CH2OH. With two alcohol functional groups, the molecule is classified as a diol. The compound is also chiral, but most studies do not distinguish the enantiomers. The compound is a colorless, bittersweet, water-soluble liquid. It is one of four common structural isomers of butanediol. It is used in flavoring, and as a precursor to some antibiotics.

Production and uses
Hydrogenation of 3-hydroxybutanal gives 1,3-butanediol:
 * CH3CH(OH)CH2CHO +  H2  →  CH3CH(OH)CH2CH2OH

Dehydration of 1,3-butanediol gives 1,3-butadiene:
 * CH3CH(OH)CH2CH2OH →  CH2=CH-CH=CH2  +  2H2O

Pharmacology
1,3-Butanediol has sedative, hypotensive and hypoglycaemic action comparable to ethanol, with the (R) enantiomer being more active. Fatty acid esters of 1,3-butanediol such as the acetoacetate or hexanoate have been researched for inducing ketogenesis.

Occurrence
1,3-Butanediol has been detected in green bell peppers, orange bell peppers, pepper (Capsicum annuum), red bell peppers, and yellow bell peppers. 1,3 Butanediol, | quote = Also referred to as 1,3-Butylene glycol, maintains FDA GRAS status as a flavor molecule.