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Chemical modification of usnic acid 2. Reactions of (+)-usnic acid with amino acids
Russian Chemical Bulletin, 2007The condensation of amino acids with (+)-usnic acid involves the 2-positioned acetyl group of the latter and gives derivatives containing an enamine fragment.
O. A. Luzina +3 more
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Anti-inflammatory activity of (+)-usnic acid
Fìtoterapìâ, 2000(+)-Usnic acid, isolated from the lichen Roccella montagnei, showed a dose-dependent anti-inflammatory activity when tested on rats, employing acute and chronic models.
Ethirajan Sukumar
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ChemInform Abstract: USNIC ACID. XIV. THE PHOTO‐OXIDATION OF USNIC ACID
Chemischer Informationsdienst, 1979AbstractDie Belichtung von (I) in Gegenwart von Sauerstoff ergibt das Spaltprodukt (l1).
K. TAKAHASHI, M. TAKANI
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Chemical modification of usnic acid 1. Reaction of (+)-usnic acid with perfluoroolefins
Russian Chemical Bulletin, 2007The reactions of the natural lichen metabolite, (+)-usnic acid, with a series of commercially available polyfluoroolefins (tetrafluoroethylene, chlorotrifluoroethylene, hexafluoropropene, perfluoro-2-methylpent-2-ene, and 1,2-dichlorooctafluorocyclohex-1-ene) afford its 7-O-polyfluoroalkyl and perfluorovinyl ethers.
G. G. Furin +5 more
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Studies in the usnic acid series. II. The condensation of (+)-usnic acid with hydroxylamine
Canadian Journal of Chemistry, 1976The results of the reaction of usnic acid (1) with hydroxylamine are presented. Four products, two isomeric isoxazoles (2 and 4), a novel oxazocine structure (3), and Δ2,11-enaminousnic acid (5) were isolated and characterized. These data clarify the earlier published results in this area.
James P. Kutney +2 more
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Canadian Journal of Chemistry, 1977
Further studies on the base catalyzed usnic acid – isousnic acid rearrangement process clarify the situation concerning (−)-usnic acid isomethoxide monoacetate (7). This substance is now shown to be a mixture of the two possible C4a epimers. These and previous data allow a mechanism to be proposed for this interesting rearrangement.
James P. Kutney, Ignacio H. Sanchez
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Further studies on the base catalyzed usnic acid – isousnic acid rearrangement process clarify the situation concerning (−)-usnic acid isomethoxide monoacetate (7). This substance is now shown to be a mixture of the two possible C4a epimers. These and previous data allow a mechanism to be proposed for this interesting rearrangement.
James P. Kutney, Ignacio H. Sanchez
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A colorimetric method for the estimation of usnic acid
Analytical Biochemistry, 1968Abstract A simple method has been developed for the estimation of usnic acid by an adaptation of the qualitative test described by Asahina and Shibata (1) with appropriate modifications under regulated conditions. Some factors affecting the formation of color have been studied.
N P, Jayasankar, G H, Towers
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Enzyme immunoassay of usnic acid in lichens
Applied Biochemistry and Microbiology, 2013An enzyme immunoassay for usnic acid in lichens was developed, the sensitivity of which was 0.1 microg/g of air-dried material (0.00001%). Polyclonal rabbit antibodies against bovine serum albumin conjugated to (+)-usnic acid under the conditions of formaldehyde condensation made it possible to determine the analyzed substance in solutions at ...
A A, Burkin +2 more
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Russian Journal of Organic Chemistry, 2009
Reactions of (+)-usnic acid with a number of substituted (halo, alkyl, alkoxy, nitro) phenylhydrazines led to the formation of the corresponding benzofuro[3,2-f]indazole derivatives or hydrazones at the acetyl group on C2, depending on the initial hydrazine.
O. A. Luzina +3 more
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Reactions of (+)-usnic acid with a number of substituted (halo, alkyl, alkoxy, nitro) phenylhydrazines led to the formation of the corresponding benzofuro[3,2-f]indazole derivatives or hydrazones at the acetyl group on C2, depending on the initial hydrazine.
O. A. Luzina +3 more
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In vitro risk assessment of usnic acid
Toxicology and Industrial Health, 2013Lichens are symbiotic organisms composed of fungi and algae and are very common in Turkey. Lichen secondary metabolites are mainly phenolic compounds produced by fungal partner of lichen symbiosis. Usnic acid (UA) is one of the most common lichen metabolites, and it was reported that to be effective for a wide range of pharmacological purposes ...
Aydin, Elanur +3 more
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