The molecular and crystal structures of gibberellin A4 and gibberellin A13 methyl esters

Abstract
The X-ray structures of gibberellin A4 methyl ester and gibberellin A13 trimethyl ester have been determined. Ring A is flattened and the crowding of C(7) by C(18) and C(15) is greater in gibberellin A13 trimethyl ester when compared to gibberellin A4.