The quest for new mild and selective modifications of natural structures: laccase-catalysed oxidation of ergot alkaloids leads to unexpected stereoselective C-4 hydroxylation.
Summary of "The quest for new mild and selective modifications of natural structures: laccase-catalysed oxidation of ergot alkaloids leads to unexpected stereoselective C-4 hydroxylation."
Laccase-catalysed oxidation of ergot alkaloids in the absence of chemical mediators allowed the unexpected isolation of the mono-hydroxylated derivatives of compounds 2-7. Structure determination by NMR techniques clearly indicated that hydroxylation took place at the C-4 benzylic position. Quite notably, the proposed protocol allowed, for the first time, functionalisation at the C-4 position of the ergoline skeleton. Depending on the absence or on the presence of a C-10 α-methoxy substituent, hydroxylation was either stereoselective (furnishing C-4α OH derivatives) or gave rise to a C-4α/C-4β OH mixture in a 2:1 ratio, respectively.
Istituto di Chimica del Riconoscimento Molecolare, C.N.R. Via Mario Bianco, 9, 20131, Milano (Italy), Fax: (+39) 02-28901239.
This article was published in the following journal.
Name: Chemistry (Weinheim an der Bergstrasse, Germany)
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/22777708
- DOI: http://dx.doi.org/10.1002/chem.201201076
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