Iron(III) oxide or ferric oxide is the inorganic compound with the formula Fe2O3. It is one of the three main oxides of iron, the other two being iron(II) oxide (FeO), which is rare; and iron(II,III) oxide (Fe3O4), which also occurs naturally as the mineral magnetite. As the mineral known as hematite, Fe2O3 is the main source of iron for the steel industry. Fe2O3 is readily attacked by acids. Iron(III) oxide is often called rust, and to some extent this label is useful, because rust shares several properties and has a similar composition; however, in chemistry, rust is considered an ill-defined material, described as Hydrous ferric oxide.
N,N′-Dicyclohexylcarbodiimide (DCC or DCCD) is an organic compound with the chemical formula (C6H11N)2C. It is a waxy white solid with a sweet odor. Its primary use is to couple amino acids during artificial peptide synthesis. The low melting point of this material allows it to be melted for easy handling. It is highly soluble in dichloromethane, tetrahydrofuran, acetonitrile and dimethylformamide, but insoluble in water.
Chalciporus piperatus, commonly known as the peppery bolete, is a small pored mushroom of the family Boletaceae found in mixed woodland in Europe and North America. It has been recorded under introduced trees in Brazil, and has become naturalised in Tasmania and spread under native Nothofagus cunninghamii trees. A small bolete, the fruit body has a 1.6–9 cm (0.6–3.5 in) orange-fawn cap with cinnamon to brown pores underneath, and a 4–9.5 cm (1.6–3.7 in) high by 0.6–1.2 cm (0.2–0.5 in) thick stipe. The rare variety hypochryseus, found only in Europe, has yellow pores and tubes.
Serpula lacrymans is one of the fungi that cause damage to timber referred to as dry rot. It is a basidiomycete in the order Boletales. The Serpula lacrymans has the ability to rapidly colonise sites through unique and highly specialised mycelium which also leads to greater degradation rates of wood cellulose.
Wolfgang Steglich is a German chemist.
Pulvinone, an organic compound belonging to the esters, lactones, alcohols and butenolides classes, is a yellow crystalline solid. Although the pulvinone is not a natural product, several naturally occurring hydroxylated derivatives are known. These hydroxylated pulvinones are produced by fungal species, such as the in Europe common Larch Bolete, or by moulds such as Aspergillus terreus.
Vulpinic acid is a natural product first found in and important in the symbiosis underlying the biology of lichens. It is a simple methyl ester derivative of its parent compound, pulvinic acid, and a close relative of pulvinone, both of which derive from aromatic amino acids such as phenylalanine via secondary metabolism. The roles of vulpinic acid are not fully established, but may include properties that make it an antifeedant for herbivores. The compound is relatively toxic to mammals.
Suillus variegatus, commonly called the velvet bolete or variegated bolete, is a species of edible mushroom in the genus Suillus. Like all bolete-like species it has tubes, and pores, instead of gills under its cap. The mushroom forms a mycorrhizal relationship with pine and occurs in North America and Eurasia.
The Steglich esterification is a variation of an esterfication with dicyclohexylcarbodiimide as a coupling reagent and 4-dimethylaminopyridine as a catalyst. The reaction was first described by Wolfgang Steglich in 1978. It is an adaptation of an older method for the formation of amides by means of DCC (dicyclohexylcarbodiimide) and 1-hydroxybenzotriazole (HOBT).
Haematopodin is the more stable breakdown product of Haematopodin B. Both compounds are found in the mushroom Mycena haematopus, although haematopodin only occurs in trace amounts in fresh fruit bodies. Similar pigments, known as batzellins and damirones, have been found in sea sponges. A chemical synthesis for haematopodin was reported in 1996. Key steps in the synthesis involved the addition of 3-[(2,4-dimethoxybenzyl)amino]-1-propanol to the indolo-6,7-quinone and cyclization of the resulting adduct with trifluoroacetic acid.
Atromentin is a natural chemical compound found in Agaricomycetes fungi in the orders Agaricales and Thelephorales. It can also be prepared by laboratory synthesis. Chemically, it is a polyphenol and a benzoquinone.
Boletocrocin is any one of a group of seven closely related organic compounds, individually named boletocrocin A through boletrocrocin G. These compounds are polyene dicarboxylic acids that include both lipophilic and polar amino acids. They were extracted from the brightly colored mushrooms Boletus laetissimus and B. rufoaureus. The boletocrocins' conjugated systems account for the intense color.
Variegatic acid is an orange pigment found in some mushrooms. It is responsible for the bluing reaction seen in many bolete mushrooms when they are injured. When mushroom tissue containing variegatic acid is exposed to air, the chemical is enzymatically oxidized to blue quinone methide anions, specifically chinonmethid anions. It is derived from xerocomic acid, which is preceded by atromentic acid and atromentin, and its genetic basis is unknown. In its oxidized form is variegatorubin, similar to xerocomorubin.
Pulvinic acids are natural chemical pigments found in some lichens, derived biosynthetically from the aromatic amino acids phenylalanine and tyrosine, via dimerization and oxidative ring-cleavage of arylpyruvic acids, a process that also produces the related pulvinones.
Norbadione A is a pigment found in the bay bolete mushroom. A polyphenol, norbadione A is related to a family of mushroom pigments known as pulvinic acids. The molecule has also been reported as a potassium salt from the mushrooms Pisolithus tinctorius and Chalciporus piperatus.
Xerocomic acid is a red-orange pigment found in fungi of the order Boletales. It is the precursor to variegatic acid, and is preceded by atromentic acid and atromentin. As an example, it is isolated from Serpula lacrymans. It is soluble in methanol. An oxidase acting on xerocomic acid is responsible for the "bluing" reaction seen in mushrooms.
Atromentic acid is a red-organge pigment found in fungi within the Boletales group. It is the precursor to variegatic acid and xerocomic acid, and is preceded by atromentin. As an example, it is isolated from Serpula lacrymans. It is soluble in methanol. Variants include homoatromentic acid. This pigment has been studied and elucidated by Wolfgang Steglich and colleagues over decades. When atromentin is oxidised with hydrogen peroxide a yellow product is produced. A sodium hydroxide solution is also yellow, but when this is neutralized with acid the red atromentic acid crystallises. Concentrated potassium hydroxide breaks up the compound to p-hydroxyphenylacetic acid and oxalic acid.
Xerocomorubin is a pigment from the fungus group, the Boletales. It is the oxidized form of isoxerocomic acid. Air oxidation is responsible its formation, and oxidizes faster to a similar pulvinic acid type pigment oxidized variant, variegatorubin. The long wavelength has an absorption at 497 nm, 106 nm higher than its precursor isoxerocomic acid. Synthesis experiments have shown tetra-acetylation by acetic anhydride and sulphuric acid. Although xerocomorubin and variegatorubin give off the same deep red color and could simultaneously occur in a mushroom, extracts from the deep red colored mushroom Boletus rubellus Krombh. identified only variegatorubin by t.l.c, leading to the question the natural abundance of xerocomorubin.
Isoxerocomic acid is a red-orange pigment found in Boletales. It is the precursor to variegatic acid, and is preceded by atromentic acid and atromentin. As an example, it is isolated from Serpula lacrymans. It is soluble in methanol. It is the isomer of xerocomic acid and precursor to xerocomorubin.
Cyclovariegatin is a pigment. Its chemical name is 1,4-Dihydro-2,7,8-trihydroxy-3-(3,4-dihydroxyphenyl)-l,4-dioxodibenzofuran. It is distinguishable by its UV-Vis spectra with maxima at 257, 296, and 430 nm. The variants cyclovariegatin-pentaacetate, cyclovariegatin-2,3',8-triacetate, and cyclovariegatin-2-acetate have also been described. It is derived from atromentin. It has been isolated from the browned skin of Suillus grevillei var. badius, and becomes the pigment thelephoric acid.
