The molecule is a C19-gibberellin, initially identified in Gibberella fujikuroi; it differs from gibberellin A1 in the absence of an OH group at C-7 and the substitution of the methylidene grouping at C-8 by alpha-OH and beta-Me groups (gibbane numberings). It is a C19-gibberellin, a lactone and a gibberellin monocarboxylic acid.
(1R,2R,5R,6R,8R,9S,10R,11S,12S)-6,12-dihydroxy-6,11-dimethyl-16-oxo-15-oxapentacyclo[9.3.2.15,8.01,10.02,8]heptadecane-9-carboxylic acid