4-Bromophenacyl Esters of Gibberellins, Useful Derivatives for High Performance Liquid Chromatography

Abstract

The 4-bromophenacyl esters of six gibberellins were prepared by crown-ether catalyzed reaction between the potassium salts of the gibberellins and 4-bromophenacyl bromide under mild non-aqueous conditions. The derivatives were stable, possessed high UV absorbance and were well separated by HPLC on μC₁₈ or cyanopropyl silica. The esters (and the corresponding TMS ethers) gave well-defined mass spectra with easily identifiable molecular ions. The combination of chromatographic and mass spectroscopic properties suggests that the derivatives may be very useful for analysis of naturally-occurring gibberellins.

Key Words:

• Gibberellins
• 4-bromophenacyl esters
• HPLC
• Mass spectra