The molecule is an alkyl-gibberellin that is gibberellin A4 carrying an extra methyl substituent at position 1alpha (4alpha using gibbane skeletal numbering).
(1R,2R,5R,8R,9S,10R,11S,12S,14S)-12-hydroxy-11,14-dimethyl-6-methylidene-16-oxo-15-oxapentacyclo[9.3.2.15,8.01,10.02,8]heptadecane-9-carboxylic acid