The synthesis of 2,2-dialkylgibberellins

Abstract

An improved synthesis of 2,2-dimethylgibberellin A₄(3), the highly active plant growth promoter, is described. The methods used were adapted to the synthesis of both radio- and stable-isotope labelled (3). The route was applied, with limited success, to the synthesis of 2,2-diethylgibberellin A₄(6). Incubation of 2,2-dimethylgibberellin A₄(3) with cultures of Gibberella fujikuroi, mutant B1 -41a, gave 2,2-dimethylgibberellin A₁(20) on a preparative scale.