jo048857s_si_001.pdf (1.39 MB)
Modulation of Chemoselectivity by Protein Additives. Remarkable Effects in the Oxidation of Hyperforin
journal contribution
posted on 2004-11-12, 00:00 authored by Luisella Verotta, Erminio Lovaglio, Olov Sterner, Giovanni Appendino, Ezio BombardelliProtein additives have a dramatic effect on the H2O2 oxidation of hyperforin, either protecting the
enolized phloroglucinol core from oxidation (human albumin) or promoting (HRP and ovalbumin)
reaction pathways derived from the intermediacy of the enollactone 4, a minor component of the
oxidation mixture in the absence of protein additives. To rationalize the exquisite specificity of
several steps and their mechanistic oddity, an organocatalytic effect is postulated. The use of protein
additives allows a straightforward and multigram preparation of the enollactone 6, an interesting
multifunctionalized scaffold for bioactivity induction and/or modulation.