5-Hydroxymethyl-, 5-Formyl- and 5-Carboxydeoxycytidines as Oxidative Lesions and Epigenetic Marks.

The four non-canonical nucleotides in the human genome 5-methyl-, 5-hydroxymethyl-, 5-formyl- and 5-carboxydeoxycytidine (mdC, hmdC, fdC and cadC) form a second layer of epigenetic information that contributes to the regulation of gene expression. Formation of the oxidized nucleotides hmdC, fdC and cadC requires oxidation of mdC by ten-eleven translocation (Tet) enzymes that require oxygen, Fe(II) and α-ketoglutarate as cosubstrates. Although these oxidized forms of mdC are widespread in mammalian genomes, experimental evidence for their presence in fungi and plants is ambiguous.

Enzymatic Formation of Rufoschweinitzin, a Binaphthalene from the Basidiomycete Cortinarius rufoolivaceus.

Dimeric polyketides are widespread fungal secondary metabolites. They occur in both ascomycetes and basidiomycetes and, therefore, across fungal phyla. Here we report the isolation of a new binaphthalene, named rufoschweinitzin, from the basidiomycete Cortinarius rufoolivaceus.

Mycenaflavin A, B, C, and D: Pyrroloquinoline Alkaloids from the Fruiting Bodies of the Mushroom Mycena haematopus.

Four so far unknown pyrroloquinoline alkaloids, yellow mycenaflavins A, B, and C, and the purple mycenaflavin D, have been isolated from the fruiting bodies of Mycena haematopus. The structures of these new alkaloids were elucidated by NMR spectroscopy and HRMS (ESI ). The mycenaflavins are structurally related to mycenarubins and haematopodins, which have been previously identified in M.

Stereo specific platelet inhibition by the natural LXR agonist 22(R)-OH-cholesterol and its fluorescence labelling with preserved bioactivity and chiral handling in macrophages.

Two synthetic LXR agonists were recently reported to inhibit collagen-induced platelet aggregation and thrombus formation in mice. We therefore studied whether also natural LXR agonists inhibit human platelet activation and whether they can be fluorescence-labelled preserving their bioactivity for LXR-related functional imaging. The natural LXR agonist 22(R)-OH-cholesterol - but not its stereoisomer 22(S)-OH-cholesterol - inhibited collagen induced platelet shape change and aggregation similar to synthetic LXR agonists in a concentration- and time-dependent manner.

Structure and absolute configuration of the fungal ansabenzoquinone rhizopogone.

The main pigment of the basidiomycete Rhizopogon pumilionus is the [13]paracyclophane derivative rhizopogone (1). The structures of 1 and the accompanying 2-acetoxyrhizopogone (5) were determined by spectroscopic studies, including 1D and 2D NMR measurements. The absolute configuration of 1 was assigned by comparison of its CD spectrum with that of secotridentoquinone (4).

Vibralactone: a lipase inhibitor with an unusual fused beta-lactone produced by cultures of the basidiomycete Boreostereum vibrans.

The structure and absolute configuration of vibralactone (1) from the cultures of the Basidiomycete Boreostereum vibrans were established by spectroscopic methods and computational methods. Vibralactone, an unusual fused beta-lactone-type metabolite, was found to inhibit pancreatic lipase with an IC50 of 0.4 microg/mL.

Pityriarubins, novel highly selective inhibitors of respiratory burst from cultures of the yeast Malassezia furfur: comparison with the bisindolylmaleimide arcyriarubin A.

Pityriasis versicolor is the most common skin mycosis in humans worldwide. Yeasts of the genus Malassezia, particularly M. furfur, a saprophyte occurring widely on human skin, are generally regarded as the causative agents.

The DMAP-catalyzed acetylation of alcohols--a mechanistic study (DMAP = 4-(dimethylamino)pyridine).

The acetylation of tert-butanol with acetic anhydride catalyzed by 4-(dimethylamino)pyridine (DMAP) has been studied at the Becke3 LYP/6-311 + G(d,p)//Becke3 LYP/6-31G(d) level of theory. Solvent effects have been estimated through single-point calculations with the PCM/UAHF solvation model. The energetically most favorable pathway proceeds through nucleophilic attack of DMAP at the anhydride carbonyl group and subsequent formation of the corresponding acetylpyridinium/acetate ion pair.

Malassezin, a novel agonist of the aryl hydrocarbon receptor from the yeast Malassezia furfur, induces apoptosis in primary human melanocytes.

Pityriasis versicolor is the most common skin mycosis in humans worldwide. Yeasts of the genus Malassezia, particularly M. furfur, a saprophyte occurring widely on human skin, are generally regarded as the causative agents.

A short diastereoselective synthesis of orthogonally protected diaminosuccinic acid derivatives.

Homogeneous, Rh-catalyzed hydrogenation of heteromeric olefinic glycine dimers presents an efficient route to diastereomerically pure, orthogonally protected diaminosuccinic acid derivatives depending on the double bond geometry of the starting material. The products were obtained as racemates.

Revision of the structures assigned to the fungal metabolites boletunones A and B.

[structure: see text] The structures recently assigned to the mushroom metabolites boletunones A (1) and B (2) are revised to those of 15-methoxycyclocalopin A (5) and isocyclocalopin A (6), respectively.

Lilacinone, a red aminobenzoquinone pigment from Lactarius lilacinus.

A red pigment, lilacinone (1), was isolated from fruit bodies of the toadstool Lactarius lilacinus. Its structure was established by 2D NMR and APCIMS methods. Compound 1 is a novel type of fungal aminobenzoquinone pigment and may be biosynthetically derived from three molecules of anthranilic acid.

Pityrialactone- a new fluorochrome from the tryptophan metabolism of Malassezia furfur.

As the main nitrogen source in Malassezia (M.) furfur, tryptophan induces the formation of fluorochromes and pigments, which makes the yeast less sensitive towards UV light. For the investigation of the fluorochromes, M.

Four lignans from Commiphora erlangeriana.

Four new lignans, two of the polygamatin-type, named erlangerin A (1) and erlangerin B (2), and two related to podophyllotoxin, named erlangerin C (3) and erlangerin D (4), were isolated from the resin of Commiphora erlangeriana, a plant occurring in Ethiopia and Somalia. The structures of these compounds including their relative stereochemistry were elucidated on the basis of spectral evidence, chemical data, and X-ray crystallographic analysis.

Draculone, a new anthraquinone pigment from the tropical lichen Melanotheca cruenta.

A new red anthraquinone, draculone, has been isolated from the corticolous tropical lichen Melanotheca cruenta (= Trypethelium cruentum = Pyrenula cruenta) together with minor quantities of the known anthraquinone pigment haematommone. The structure of draculone was determined as 2-acetyl-1,3,4,6,8-pentahydroxyanthraquinone by spectroscopic methods.

Total syntheses of the marine pyrrole alkaloids polycitone A and B.

Polycitone B (2) was obtained in four steps from pyrrole dicarboxylic acid 3, including Friedel-Crafts reaction of the corresponding acid chloride with anisole. The conversion of 2 into polycitone A (1) was achieved in two steps via Mitsunobu alkylation of the pyrrolic NH group. The synthesis of polycitone A proceeds in 18% overall yield and offers the possibility of varying the substituents on the pyrrole ring.

Studies on the biosynthesis of striatal-type diterpenoids and the biological activity of herical.

Feeding experiments with specifically 13C-labeled glucose disclosed that the diterpenoid part of the striatals/striatins is formed via the mevalonate pathway, whereas the pentose moiety originates either via glucuronic acid (70%) or the pentose phosphate cycle (30%). Application of radioactively labeled herical to cultures of Hericium ramosum demonstrates the pivotal role of this cyathane-xyloside in striatal biosynthesis. Herical inhibits a large spectrum of fungi and bacteria and shows cytotoxic and hemolytic properties.

Pityriacitrin -- an ultraviolet-absorbing indole alkaloid from the yeast Malassezia furfur.

As the main nitrogen source in Malassezia furfur, tryptophan induces the formation of fluorochromes and pigments, which make the yeast less sensitive to UV light. To detect a chemical UV filter, M. furfur (CBS 1878) was incubated at 30 degrees C for 14 days on a pigment-inducing medium and agar extracts were purified by column chromatography, preparative TLC and HPLC.

Blennione, a green aminobenzoquinone derivative from Lactarius blennius.

A green pigment, blennione (1), was isolated from fruit bodies of the toadstool Lactarius blennius. Its structure was established by 2D NMR methods and confirmed by a biomimetic synthesis. Compound 1 represents a diphenylquinone derivative, which may be formed biosynthetically from two 3,6-dihydroxyanthranilic acid units.

Polyene pigments from fruit-bodies of boletus laetissimus and B. rufo-aureus (basidiomycetes).

From fruit-bodies of the Japanese mushroom Boletus laetissimus two polyene pigments boletocrocin A and B were isolated and their structures determined by spectroscopic methods. The compounds represent diamides of hexadecaheptaenedioic acid with isoleucine and either aspartic acid or asparagine. The L-configuration of the amino acids was established after acid hydrolysis.