1376979-91-7Relevant academic research and scientific papers
Abscinazole-E2B, a practical and selective inhibitor of ABA 8′-hydroxylase CYP707A
Okazaki, Mariko,Kittikorn, Monrudee,Ueno, Kotomi,Mizutani, Masaharu,Hirai, Nobuhiro,Kondo, Satoru,Ohnishi, Toshiyuki,Todoroki, Yasushi
experimental part, p. 3162 - 3172 (2012/07/14)
We developed abscinazole-E2B (Abz-E2B), a practical and specific inhibitor of abscisic acid (ABA) 8′-hydroxylase (CYP707A), by structural modification of abscinazole-E1 (Abz-E1), another compound we developed. A butoxy group was introduced to Abz-E2B instead of the tosylate group of Abz-E1, in expectation of better water solubility, because the calculated log P value of Abz-E2B is 3.47, which is smaller than that of Abz-E1 (4.02). The water solubility of Abz-E2B was greater than 90% at a concentration of 100 μM, at which the solubility of Abz-E1 was 20%. The enzyme specificity was improved significantly. In in vitro assays constructed using recombinant enzymes, (±)-Abz-E2B was a considerably weaker inhibitor than (±)-Abz-E1 for CYP701A, a GA biosynthetic enzyme, which is a target of S-uniconazole (S-UNI), a lead compound of Abz-E1. (±)-Abz-E2B application to plants resulted in improved desiccation tolerance and an increase in endogenous ABA, with little retardation of growth. We also prepared optically pure Abz-E2B and determined its absolute configuration. The R-enantiomer of Abz-E2B was the more potent inhibitor of CYP707A, unlike UNI, whereas both enantiomers were markedly less effective than S-UNI in inhibiting CYP701A. Because S-Abz-E2B arrested the growth of rice seedlings at 100 μM, probably because of off-target effects, R-Abz-E2B should be used as a chemical tool for research focusing on CYP707A when 100 μM or higher concentration is required, although (±)-Abz-E2B may be useful as an alternative option at a lower concentration.
