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Radiolysis of Quercetin in Methanol Solution: Observation of Depside Formation
Journal of Agricultural and Food Chemistry, 2002Radiolysis of the flavonol quercetin, a natural antioxidant, was performed in methanol. The degradation process was followed by HPLC analyses. The major product was identified as a depside (Q1) by NMR and LC-MS. The G(Q1) radiolytic factor was plotted versus the initial concentration of quercetin.
Abdelghafour, Marfak +5 more
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A theory of biogenesis of lichen depsides and depsidones
Proceedings of the Indian Academy of Sciences - Section A, 1944Lichen depsides and depsidones are considered to arise from a common source (XIV) which originates from aldol condensation between a hexose and a biose and elimination of water. Oxidation and reduction lead to various modifications of this C8 unit and increase in the length of the sidechain arises from condensation with simple sugars and reduction ...
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New Depsides in Stirtonia ramosa (Ascomycotina, Arthoniaceae)
The Bryologist, 1990Stirtonia ramosa, a corticolous crustose lichen from the Andaman Islands, contains two new para-depsides, 4-O-demethylsuperconfluentic and 2'-O-methylnorsuperphyllinic acids. Chemical structures are proposed from microchemical identification of the hydrolysis products of the depsides and their methyl esters.
Chicita F. Culberson +3 more
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Synthesis of depsides and their biological activity
Synthesized depsides were modified based on the core structure of jaboticabin, to enhance its biological activities. Desired depsides were synthesized through an esterification with methyl 2-(2- hydroxyphenyl) acetate (NT0) and a carboxylic acid compound. DCC and DMAP were required to activate the carboxylic group and solvent used was DCM. 2-(2-Methoxy-openaire +1 more source
Stenosporic acid, a new depside in Ramalina stenospora
Phytochemistry, 1970Abstract Column chromatography of an extract of the lichen Ramalina stenospora Mull. Arg. yielded usnic acid (0·013%), a mixture of atranorin and chloroatranorin (0·007%), perlatolic acid (0·40%) and a new para-depside, stenosporic acid (0·37%). Stenosporic acid was proven to be 4-(2-hydroxy-6-propyl-p-anisate)-6-pentyl-β-resorcylic acid.
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Synthesis of para -olivetol depsides
Australian Journal of Chemistry, 1974The unambiguous synthesis of the lichen depsides, anziaic, perlatolic, 2'- O -methylanziaic, 2- O - methylperlatolic, 2'- O -methylperlatolic, 4- O -demethylplanaic, planaic, imbricaric and stenosporic acids is reported. Where necessary the phenolic and carboxy groups of the intermediate phenols were protected by O -benzylation until after the depside ...
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New reagents for the synthesis of depsides
Tetrahedron, 1965S. Neelakantan +2 more
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