Description | D-Hexanolactone is the lactone of 5-hydroxy-Hexanoic acid. Lactones are internal esters that exist in equilibrium between their closed (lactone) and open (hydroxy acid) forms in an aqueous environment. The lactone/hydroxy acid ratio at equilibrium is pH-dependent, with the closed form being favored at lower pH values, and can be greatly influenced by structural features of the lactone such as the ring size, substituents on the ring and the presence of double bonds within the ring. Many drugs and endogenous compounds are lactones or hydroxy acids and an enzyme capable of catalyzing the interchange between the open and closed forms in vivo could have pronounced effects upon their biological activity and/or distribution.
d-Hexanolactone is the substrate of paraoxonases (PON) in humans. Human PON1 hydrolyzes over 30 different lactones (cyclic esters) and catalyzes the reverse reaction (lactonization) of a broad range of hydroxy acids. Hydroxy acid lactonization or lactone hydrolysis is catalyzed until equilibrium between the open and closed forms is reached. (PMID 15772423, 12963475, 12963475) |