Norstictic acid

Purvis, O. W., Elix, J. A., Broomhead, J. A. Jones G. C. (1987). The occurrence of copper-norstictic acid in lichens from cupriferous substrata. Lichenologist, 19, 193-203. 

Cryptostictic acid Norstictic acid Stictic acid Triglyceride ... 

Potassium hydroxide (20% KOH in 100 ml HjO) is a useful reagent to differentiate between quinones and compounds of the pulvinic acid group the orange or red colour of the quinones turns to deep red. Atranorin and related compounds give a deep yellow colour with KOH. Norstictic acid forms a deep red microcrystalline complex with KOH. 

Mass spectrometry is another useful tool for the identification and structural elucidation of lichen substances. Tlje principles of the method are given in a review by Lehmann and Schulten (1976). The mass spectra (MS) of numerous depsides, depsidones, depsones, dibenzofuranes and diphenylbutadienes have been discussed by Huneck et al. (1968a). In the same year, Letcher (1968) published the MS of some pulvinic acid derivatives. Martinez and Mestres (1972) recorded the MS of depsidones derived from norstictic acid, and Holland and... 

Norstictic acid clusters of yellowish long lamellae... 

Deriv Pentaacetylnorstictic acid, prisms (CHClj-MeOH), mp 212 °C, from norstictic acid with AC2O-H2SO4... 

Norstictic acid, physodic acid, evemic acid, usnic acid, salazinic acid, fumar-protocetraric acid, protocetraric acid, atranorin and zeorin isolated from different lichen species are relatively strong antioxidant, antimicrobial and anticancer agents (Kosanic et al. 2010, 2013, 2014 Manojlovic et al. 2012 Rankovic et al. 2014). 

Rankovic B, Kosanic M, Stanojkovic T et al (2012) Biological activities of Toninia Candida and Usnea barbata together with their norstictic acid and usnic acid constituents. Int J Mol Sci 13 ... 

In the study described by Rankovic et al. (2012), lichen compounds, norstictic acid isolated from Toninia Candida and usnic acid from Usnea barbata, exhibited high antioxidant potential in vitro, but it should be noted that the norstictic acid had a larger antioxidant capacity. 

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