Definition: One of the FURANS with a carbonyl thereby forming a cyclic lactone. It is an endogenous compound made from gamma-aminobutyrate and is the precursor of gamma-hydroxybutyrate. It is also used as a pharmacological agent and solvent.
butyrolactone I [ alpha-oxo-beta-(4-hydroxyphenyl)-gamma-(4-hydroxy-m-3,3-dimethylallylbenzyl)-gamma-methoxycarbonyl-gamma-butyrolactone ] selective inhibitor of cdk2 & cdc2 kinase; structure given in first source