The molecule is a C19-gibberellin, initially identified in Pyrus communis. It differs from gibberellin A1 in the absence of OH groups at C-2 and -7 and the presence of a beta-OH at C-9 (all gibbane numbering). It is a C19-gibberellin, a gibberellin monocarboxylic acid and a lactone.
(1R,2R,5R,7R,8R,9S,10R,11R)-7-hydroxy-11-methyl-6-methylidene-16-oxo-15-oxapentacyclo[9.3.2.15,8.01,10.02,8]heptadecane-9-carboxylic acid