Umbelliferone
| Umbelliferone | |
|---|---|
 |
|
|
7-Hydroxychromen-2-one |
|
|
Other names
7-hydroxycoumarin, hydrangine, skimmetine, beta-umbelliferone |
|
| Identifiers | |
| CAS number | 93-35-6  |
| PubChem | 5281426 |
| ChemSpider | 4444774 |
| ChEBI | CHEBI:27510  |
| ChEMBL | CHEMBL51628 |
| Jmol-3D images | Image 1 |
|
|
|
|
| Properties | |
| Molecular formula | C9H6O3 |
| Molar mass | 162.14 g/mol |
| Exact mass | 162.031694 |
| Melting point |
230 °C (decomposes) |
 (verify) (what is:  / ?)Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) |
|
| Infobox references | |
Umbelliferone, also known as 7-hydroxycoumarin, hydrangine, skimmetine, and beta-umbelliferone, is a widespread natural product of the coumarin family. It occurs in many familiar plants from the Apiaceae (Umbelliferae) family such as carrot, coriander and garden angelica, as well plants from other families such as the mouse-ear hawkweed. It is a yellowish-white crystalline solid that has a slight solubility in hot water, but high solubility in ethanol. It absorbs ultraviolet light strongly at several wavelengths. Despite several indications that this chemical is photomutagenic, it is used in sunscreens.[1][dead link] Umbelliferone has been reported to have antioxidant properties.[2]
Contents |
[edit] Chemical synthesis
Umbelliferone is traditionally synthesized using the Pechmann condensation, from resorcinol and formylacetic acid (generated from malic acid in situ).
A newer synthesis uses methyl propiolate and a palladium catalyst.
[edit] Ultraviolet fluorescence
Umbelliferone absorbs strongly at 300, 305 and 325 nm, with log ε values of 3.9, 3.95 and 4.15 respectively, and it fluoresces blue in both ultraviolet and visible light. The powerful absorption at three different wavelengths, coupled with the fact that the energy is dissipated safely as visible light, make umbelliferone a useful sunscreen agent. The absorption changes in alkaline solution, since the phenolic hydroxyl group is deprotonated (pKa = 7.7).
[edit] Uses
The ultraviolet activity of umbelliferone led to its use as a sunscreen agent, and an optical brightener for textiles. It has also been used as a gain medium for dye lasers. Umbelliferone can be used as a fluorescence indicator for metal ions such as copper and calcium. It acts as a pH indicator in the range 6.5-8.9.
[edit] Derivatives of umbelliferone
Umbelliferone is the parent compound for a large number of natural products. Herniarin or 7-O-methylumbelliferone (7-methoxycoumarin) occurs in the leaves of water hemp (Eupatorium ayapana) and rupturewort. O-glycosylated derivatives such as skimmin (7-O-β-D-glucopyranosylumbelliferone) occur naturally and are used for the fluorimetric determination of glycoside hydrolase enzymes. Isoprenylated derivatives are also widespread, such as marmin (found in grapefruit skin and in the bark of the Bael tree) and furocoumarins such as marmesin, angelicin, and psoralen.
-
Herniarin and marmin, umbelliferone derivatives
[edit] See also
[edit] References
- ^ cancerweb
- ^ "UMBELLIFERONE". www.chemicalland21.com. http://www.chemicalland21.com/lifescience/phar/UMBELLIFERONE.htm. Retrieved 21 November 2011.
[edit] Further reading
- Dean, F.M. (1963). Naturally Occurring Oxygen Ring Compounds. London: Butterworths. ISBN 9780408267502.
- Joule, J.A.; Mills, K. (2000). Heterocyclic Chemistry (4th ed.). Oxford: Blackwell Science. ISBN 9780632054534.
- Barton, D.H.R.; Nakanishi, K.; Meth-Cohn, O., eds (1999). Comprehensive Natural Products Chemistry. 2. Oxford: Elsevier. p. 677. ISBN 9780080431543.
[edit] External links
|
|||||||||||||||||
