Synthesis of optically active cyclohexanone analogs of the plant hormone abscisic acid

Abstract

The abscisic acid analogs (−)-(4R,5R)-, (+)-(4S,5S)-, and (−)-(4S,5R)-4(1E,3Z)-4-(4-carboxy-3-methyl-1,3-butadienyl)-4-hydroxy-3,3,5-trimethylcyclohexanones (dihydroabscisic acids), and (−)-(4S,5R)-, (+)-(4R,5S)-, and (−)-(4R,5R)-4(Z)-4-hydroxy-4-(5-hydroxy-3-methylpent-3-en-1-ynyl)-3,3,5-trimethylcyclohexanones were synthesized from a common precursor, (−)-(6R)-2,2,6-trimethylcyclohexan-1,4-dione, which was readily prepared by the fermentation of oxoisophorone with bakers' yeast. Keywords: abscisic acid, dihydroabscisic acid, acetylenic analogs, optically active analogs, plant growth regulators.