Umbelliferone, properties

Many fluorescence immunoassays have utilized umbelliferone, a 7-hydroxycoumarin (excitation and emission maxima of 360 nm and 447 nm, respectively), as the fluorescence reporter group. Normal serum, however, exhibits emission maximum at 520 nm and excitation maxima of 330 nm and 440 nm. Even with this overlap between the spectra of umbelliferone and normal serum, umbelliferone has one property that makes it suitable for fluorescence immunoassays conversion of the free hydroxyl group to an ester or a glucoside effectively quenches the fluorescence of umbelliferone, and hydrolysis of the ester or glycoside allows for recovery of fluorescence. It is... 

Other flavones in passionflower (vitexin, coumerin, umbelliferone) have not been well characterized for their neuropharmacological action. Vitexin (derived from millet in one study) was found to have antithyroid properties. The remaining constituents, maltol and harman alkaloids, are present in small quantities and not presumed to contribute to the psychotropic effects (Meier 1995). Harman alkaloids in greater quantities are hallucinogenic and presumed to work through 5-HT receptors (Grella et al. 1998). 

These reactions are generally fast and formally allow us to use any known fluorogenic, chromogenic, or luminogenic substrate, when the detectable property is based on an ionizable XH group (jfr-nitrophenol, umbelliferone, etc.) (Klein and Reymond, 1998). The antibody catalyzed... 

Geiparvarin (898) isolated from Geijera parviflora, reported to have antitumor properties, was first synthesized by Smith et al., who thereby also established the stereochemistry of the double bond. The synthesis consisted of the aldol addition of the aldehyde 899 (R = CH2CHO), prepared from umbelliferone (899, R = H), to 5-ethyl-2,2-dimethyl-2/f-furan-3-one (900) when both isomers of 898 were obtained, the ( )-isomer being identical to the natural product. The synthesis of Jackson and Raphael (Scheme 67) starts with the acetylenic alcohol 901, once readily available, but no longer, because of the hazards associated with its handling (cf. Vol. 4, p. 558, Ref. 733). The... 

Sweet potato also contains the coumarins scopoletin (3, / =H), aesculetin (3, i =OH), and umbelliferone (3, J =OMe) compounds, which have anticoagulation properties and are postulated to inhibit HIV replication (Weiss and Finkelmann, 2000). The sweet potato could be considered as an excellent novel source of natural health-promoting compounds, such as anthocyanins, for the functional food market. Ultimately, this could increase utilization and demand for the crop by consumers, and the food industry. 

This characteristic property was first observed with umbelliferone (7-hy-droxycoumarin, 9) and this compound was applied to human hair as an optical bleach. However, its use became limited due to the unsatisfactory binding to hair. The introduction of a methyl group led to a desirable absorption of these compounds [539,540]. It was found that the absorption is optimal in weak acid... 

Umbelliferone has fungistatic properties. Chamazulene, a major component of the oil, has shown pain-relieving, wound-healing, antispasmodic, anti-inflammatory, and antimicrobial properties a-bisabolol, another constituent of the oil, has shown anti-inflammatory, antiedemic, antimicrobial, and in vitro antipeptic activities the cyclic spiro ethers (e.g., cw/trani-en-yn-dicyloethers) have shown antimicrobial, anti-inflammatory, antianaphylactic, and antispasmodic activities (jiANGSu LIST AND horhammer martindale MCKENNA). Anti-inflammatory and... 

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