Melvyn Gill

Pigments of fungi (Macromycetes)

This review summarises progress reported in the chemical, biological and mycological literature dealing with the isolation, characterisation and chemistry of pigments manufactured by those fungi that produce conspicuous fruit bodies (Macromycetes). Work that has appeared in the primary literature between September 1998 and May 2003 is covered, and 99 references are cited.

The first stereospecific approach to both enantiomers of mellein

Abstract (R)-(−)-Mellein 1 and its (S)-(+)-antipode 2 are prepared in six steps and ca. 30% overall yield form (R)- and (S)-propylene oxide, 3 and ent- 3 , respectively.

Antibacterial metabolites from Australian macrofungi from the genus Cortinarius

In this study, ethyl acetate and aqueous fractions from 117 collections of Australian macrofungi belonging to the mushroom genus Cortinarius were screened for antimicrobial activity against Staphylococcus aureus and Pseudomonas aeruginosa. Overall, the lipophilic fractions were more active than the aqueous fractions. The ethyl acetate fractions of most or all collections of 13 species, namely Cortinarius ardesiacus, C. archeri, C. austrosaginus, C. austrovenetus, C. austroviolaceus, C. coelopus, C. [Dermocybe canaria](2), C. clelandii, C. [D. kula], C. memoria-annae, C. persplendidus, C. sinapicolor, C. vinosipes and forty seven collections of un-described Cortinarius species exhibited IC(50) values of 0.09 mg/mL against S. aureus. In contrast, most or all collections of only four species, namely C. abnormis, C. austroalbidus, C. [D. kula], C. persplendidus, and eleven un-described Cortinarius collections exhibited similar effects against P. aeruginosa (IC(50) <or= 0.09 mg/mL). Anthraquinonoid pigments isolated from C. basirubescens together with emodin physcion and erythrogluacin were assessed for their antimicrobial activity. The fungal octaketides austrocortilutein, austrocortirubin, torosachrysone, physcion and emodin were found to strongly inhibit the growth of S. aureus (IC(50) 0.7-12 microg/mL) whereas only physcion and emodin exhibited potency against P. aeruginosa (IC(50) 1.5 and 2.0 microg/mL, respectively).

Dihydroanthracenones from Dermocybe splendida and related fungi

Abstract (3 S )-Atrochrysone and (3 S )-torosachrysone have been isolated from Australian toadstools belonging to the genus Dermocybe ; labelling experiments show that sodium [2- 13 C]acetate and [Me- 13 C]methionine are efficiently incorporated into torosachrysone by intact fruit bodies.

SYNTHESIS AND ABSOLUTE STEREOCHEMISTRY OF THYSANONE

Abstract The structure and absolute stereochemistry of thysanone 3 , a fungal benzoisochromanquinone with potent human rhinovirus 3C-protease inhibitory activity, is established by the total synthesis of its antipode 1 from ( S )-propylene oxide.

Anthraquinones from the genus Cortinarius

Abstract The anthraquinones 6-methylxanthopurpurin-3-methyl ether, xanthorin, and 1,4-dihydroxy-2-methoxy-7-methyl-9,10-anthraquinone (austrocortinin) have been isolated from fruit bodies of a red Australian toadstool belonging to the genus Cortinarius ; austrocortinin is reported for the first time as a natural product.

Constituents of the higher fungi. Part XII. Identification of involutin as (–)-cis-5-(3,4-dihydroxyphenyl)-3,4-dihydroxy-2-(4-hydroxyphenyl)-cyclopent-2-enone and synthesis of (±)-cis-involutin trimethyl ether from isoxerocomic acid derivatives

Xerocomic and isoxerocomic acids have been synthesised and converted into the corresponding 2,5-diaryl-4-methoxycyclopent-4-ene-1,3-diones. Reduction of the dione from isoxerocomic acid has given racemic involutin trimethyl ether (IV); this identifies involutin as (III). Isoxerocomic acid is readily oxidised to xerocomorubin; this is compared with the naturally occurring variegatorubin.

Constituents of Agaricus xanthodermus Genevier: The First Naturally Endogenous Azo Compound and Toxic Phenolic Metabolites

Abstract Extraction of fresh sporophores of the fungus Agaricus xanthodermus yields 4,4′-dihydroxy-azobenzene, phenol, p-quinol, and 4,4′-dihydroxybiphenyl. This is the first report of an azo compound arising endogenously in nature, while phenol, p-quinol and 4,4′-dihydroxybiphenyl have not previously been isolated from higher fungi. Phenol is present in fruitbodies in sufficiently high concentration to account for the toxicity of A. xanthodermus.

Total synthesis of enantiopure 1,3-dimethylpyranonaphthoquinones including ventiloquinones E, G, L and eleutherin.

A new synthetic approach to enantiopure pyranonaphthoquinones is described. (S)-Mellein 10, prepared in 6 steps from (S)-propylene oxide 16, is converted stereospecifically to the (1R,3S)-dimethylpyran 15. The pyran 15 is then converted to the benzoquinone 14, which undergoes regiospecific Diels-Alder reactions with a variety of oxygenated butadienes to give pyranonaphthoquinones including ventiloquinones E, G, L, eleutherin and ent-deoxyquinone A.

New tetrahydroanthraquinones from the genus Cortinarius

Abstract Austrocortirubin and austrocortilutein the first hydroxylated tetrahydro-anthraquinones from Basidiomycetes, have been isolated from an Australian toadstool belonging to the subgenus Dermocybe of Cortinarius .