mevalonic acid

A precursor in the formation of terpenoids and steroids. It has the formula CH₂OHCH₂C(OH)(CH₃)CH₂COOH. Biosynthesis of gibberellins, cytokinins, and abscisic acid is from mevalonic acid. Certain growth retardants, e.g. Amo-1618 and CCC (chlorcholine chloride), are believed to act by blocking the step from geranylgeranylpyrophosphate to kaurene in the mevalonic acid synthesis pathway, so preventing gibberellin synthesis.