Anthracenone ABA analogue as a potential photoaffinity reagent for ABA-binding proteins

An anthracenone analogue of abscisic acid (ABA) was synthesized as a potent ial photoaffinity reagent and tested for biological activity. Reaction betw een 10,10'-dimethoxy-9-anthrone with two equivalents of the lithiated diani on of cis-3-methylpent-2-en-4-yn-1-ol afforded an acetylenic alcohol key in termediate. Subsequent reduction of the triple bond, functional group manip ulation of the side chain alcohol and deprotection of the dimethoxy protect ed anthrone provided anthracenone ABA analogue 7 as a potential photoaffini ty reagent for ABA-binding proteins. The effect of natural ABA and the pote ntial photoaffinity anthracenone ABA 7 on corn cell growth was determined a t various concentrations. The results show that anthracenone ABA 7 is perce ived as ABA-like, although producing less inhibition than ABA itself. For e xample, 7 at 33 mu M produces approximately the same inhibition as ABA at 1 0 mu M. Crown Copyright (C) 2000 Published by Elsevier Science Ltd. All rig hts reserved.