SYNTHESIS AND BIOLOGICAL ACTIVITY OF ALLENIC ANALOGUES OF ABSCISIC ACID

Article abstract of DOI:10.1016/0031-9422(91)83174-J

Key Word Index - Lemma gibba; Lemnaceae; abscisic acid; ABA; ABA analogue; allene; turion; growth inhibition.Abstract - Novel allenic analogues of abscisic acid (ABA) were synthesized and tested for ABA activity.The allene functional group was introduced by one of two methods: base catalysed isomerization of an enyne to an enallene conjugated to a ketone, or reduction of a 2-butyn-1,4-diol to an allenic alcohol.A 3:1 mixture of (E)- and (Z)-3-methyl-5-(4',4'-ethylenedioxy-2',6',6'-trimethylcyclohex-2'-en-1'-ylidene)-2,4,5-pentatrienoic acids strongly inhibited growth of axenic duckweed (Lemna gibba) causing a 50percent reduction in frond number at 60 μgl^-1 over 7 days in continuous light.Racemic ABA caused the same inhibition at 130 μgl^-1.The mixture caused the production of turion-like structures, an effect known hitherto to be induced only by short photoperiods or by certain concentrations of ABA.