Partial synthesis of the 15β-hydroxygibberellins A67 and A68 and of 15β-hydroxygibberellins A1 and A3

Abstract

The structures of two new higher plant gibberellins, A₆₇(7) and A₆₈(4), have been established by their partial synthesis from gibberellin A₃(2). In addition, 15β-hydroxyGA₁(8) and 15β-hydroxyGA₃(3) have also been prepared from GA₃(2). The preparation of GA₆₈(4) from GA₃(2) involves the novel displacement of a bridgehead hydroxy group by chlorine under the conditions of the Swern oxidation in which di-isopropylethylamine is replaced by triethylamine.