Two‐dimensional NMR analysis of the phytohormone gibberellin A 3

The complete analysis of the 1 H NMR spectra of the phytohormone gibberellin A 3 and its 3,13‐diacetyl derivative has been performed. ASIS and 2D J ‐resolved spectroscopy were used to disentangle the complex spin systems, which were further analysed by 1 H‐ 1 H homocorrelated spectroscopy and spin decoupling. 2D 1 H‐ 13 C shift correlated spectra not only supported the identification of individual protons but also allowed the clarification of some controversial 13 C assignments.