Sesquiterpene-like inhibitors of a 9-cis-epoxycarotenoid dioxygenase regulating abscisic acid biosynthesis in higher plants.

Abscisic acid (ABA) is a carotenoid-derived plant hormone known to regulate critical functions in growth, development and responses to environmental stress. The key enzyme which carries out the first committed step in ABA biosynthesis is the carotenoid cleavage 9-cis-epoxycarotenoid dioxygenase (NCED). We have developed a series of sulfur and nitrogen-containing compounds as potential ABA biosynthesis inhibitors of the NCED, based on modification of the sesquiterpenoid segment of the 9-cis-xanthophyll substrates and product.

Synthesis and biological activity of tetralone abscisic acid analogues.

Bicyclic analogues of the plant hormone abscisic acid (ABA) were designed to incorporate the structural elements and functional groups of the parent molecule that are required for biological activity. The resulting tetralone analogues were predicted to have enhanced biological activity in plants, in part because oxidized products would not cyclize to forms corresponding to the inactive catabolite phaseic acid. The tetralone analogues were synthesized in seven steps from 1-tetralone and a range of analogues were accessible through a second route starting with 2-methyl-1-naphthol.

An affinity probe for isolation of abscisic acid-binding proteins.

An affinity probe has been developed for isolation of receptor proteins that bind the plant hormone abscisic acid (ABA). The structural features required for biological activity have been preserved, and the probe has been demonstrated to bind to known ABA-binding proteins.

Oxidation of 8'-hydroxy abscisic acid in Black Mexican Sweet maize cell suspension cultures.

In a biotransformation study to prepare deuterium labelled phaseic acid (PA) from deuterated abscisic acid (ABA), the product contained fewer deuterium atoms than expected. Thus, spectroscopic data of isolated deuterated PA prepared from biotransformation of (+)-5,8',8',8'-d4-ABA in maize (Zea mays L. cv.