title: Synthesis, Biological Activity, and Metabolism of 8',8',8'-Trideuteroabscisic Acid.
abstract: An 8',8',8'-trideuterated analog of abscisic acid (ABA) was diastereoselectively synthesized as a new analog of ABA that is resistant to 8'-hydroxyIation, the first metabolic reaction of ABA, owing to the primary kinetic isotope effect. (+)-8',8',8'-Trideutero-ABA showed long-term activity in the rice elongation assay. The rate of metabolism of this analog in rice cell suspension culture was about two fold slower than that of (+)-ABA. The concentration of 8',8'-dideuterophaseic acid produced was about 1/3 that of phaseic acid converted from (+)-ABA. This result indicated that the long-lasting activity of the (+)-trideutero-ABA in the rice assay was the result of the delayed 8'-hydroxylation as expected.
authors.affiliation: a Division of Applied Life Sciences, Graduate School of Agriculture , Kyoto University , Kitashirakawa-oiwake-cho, Sakyo-ku, Kyoto 606-01 , Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Todoroki
authors.affiliation: a Division of Applied Life Sciences, Graduate School of Agriculture , Kyoto University , Kitashirakawa-oiwake-cho, Sakyo-ku, Kyoto 606-01 , Japan.
authors.forename: S
authors.initials: S
authors.lastname: Nakano
authors.affiliation: a Division of Applied Life Sciences, Graduate School of Agriculture , Kyoto University , Kitashirakawa-oiwake-cho, Sakyo-ku, Kyoto 606-01 , Japan.
authors.forename: N
authors.initials: N
authors.lastname: Hirai
authors.affiliation: a Division of Applied Life Sciences, Graduate School of Agriculture , Kyoto University , Kitashirakawa-oiwake-cho, Sakyo-ku, Kyoto 606-01 , Japan.|b Department of Applied Biological Chemistry, Faculty of Agriculture , Niigata University , 2-8050 Ikarashi, Niigata 950-21 , Japan.
authors.forename: T
authors.initials: T
authors.lastname: Mitsui
authors.affiliation: a Division of Applied Life Sciences, Graduate School of Agriculture , Kyoto University , Kitashirakawa-oiwake-cho, Sakyo-ku, Kyoto 606-01 , Japan.
authors.forename: H
authors.initials: H
authors.lastname: Ohigashi
keywords: 8′,8′,8′-trideuteroabscisic acid; abscisic acid; phaseic acid; primary kinetic isotope effect; rice cell suspension culture