Umbelliferone ethers

The umbelliferone ether structure 1 was suggested for a natural product which was isolated from galbanum resin Does this structure fit the NMR results 48 Is it possible to give a complete spectral assignment despite lack of resolution of the proton signals at 200 MHz What statements can be made about the relative configuration ... 

FA003 Hofer, O., M. Widhalm, and H. Greger. Circular dichroism of ses-quiterpene-umbelliferone ethers and structure elucidation of a new derivative isolated from the gum resin asafetida . Monatsh Chem 1984 115(10) 1207-1218. 

Alkylation of umbelliferone with chloromethyl esters of various ahphatic acids affords the corresponding acyloxymethyl ethers (e.g. 27) in good yields [38]. These substrates undergo lipase/esterase-catalyzed hydrolysis in buffer to form umbelliferone (Scheme 1.9) [39]. The mechanism probably involves an unstable hemi-acetal intermediate, which spontaneously reacts to formaldehyde andumbeUiferone... 

The high sensitivity and simplicity of fluorescence spectroscopy justify the common use of this technique in these fields. It has been widely applied to characterizing citric juices and investigating their alteration, such as the adulteration of lemon oil with grapefruit oil. While grapefruit oil contains an ether of umbelliferone, which is released on acid hydrolysis, lemon oil contains other nonfluorescent hydroxycoumarins. The adulteration of saffron, which is relatively frequent because of its high price, can be detected using TLC with fluorimetric detection. Saffron can be differentiated from some substitutes because it is not fluorescent vmder UV radiation. 

Sesquiterpene coumarins constitute an interesting family of natural products. They are a group of molecules whose structures are based on a C15 terpene moiety linked through either an ether linkage with the 7-hydroxy group of umbelliferone. 

Unfortunately, many natural coumarins have been assigned trivial names, mostly botanically derived. Although these can facilitate discussion, to a considerable extent they serve to confuse, especially since many of the endings (e,g, -ol, -one) are not at all consistent with structure. Thus umbelliferone (2) is a phenol while osthol (143) is the methyl ether of osthenol (142). Structurally closely related coumarins can have markedly different names aculeatin (249) is the epoxide of toddaculin (248), both of which occur in Toddalia aculeata, while conversely almost identical trivial names can be given to structurally quite dissimilar coumarins, e. g. ferudenol (339) and ferulenol (481). Not infrequently, the same coumarin isolated by different workers from different plant sources is given two or even three trivial names and even enantiomers are known with distinct trivial names, e.g. marmesin (103) and nodakenetin (104). 

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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