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PubMed · 2183798

3-Hydroxycoumarins: first direct preparation from coumarins using a Cu2(+)-ascorbic acid-O2 system, and their potent bioactivities.

K Aihara·T Higuchi·M Hirobe
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Abstract

First direct 3-hydroxylation of a coumarin ring via a purely chemical system, previously only possible using cytochrome P-450, was successfully conducted by a Cu2(+)-ascorbic acid-O2 system; the two 3-hydroxycoumarins obtained were novel compounds, 3-hydroxyscopoletin and 3-hydroxyisoscopoletin. 5-Lipoxygenase and alpha-D-glucosidase inhibitory activities of coumarins greatly increased through 3-hydroxylation. 3-Hydroxyscopoletin and 3-hydroxyumbelliferone had a high inhibitory potency for 5-lipoxygenase and for alpha-D-glucosidase respectively; they serve as lead compounds for new drugs.

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Arachidonate 5-LipoxygenaseAscorbic AcidBiological AssayChemical PhenomenaChemistryChromatography, High Pressure LiquidCopperCoumarinsGlycoside Hydrolase InhibitorsHydroxylationOxygenScopoletinStructure-Activity RelationshipUmbelliferonesJournal ArticleResearch Support, Non-U.S. Gov't

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K Aihara, T Higuchi, M Hirobe. 1990-04-16. 3-Hydroxycoumarins: first direct preparation from coumarins using a Cu2(+)-ascorbic acid-O2 system, and their potent bioactivities.. https://doi.org/10.1016/0006-291x(90)91689-p

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