Daldinia concentrica

The naphthalene derivatives (171, 172), from Daldinia concentrica (Ascomycetes), were significantly active towards C. elegans (10, 25 (ig/ml) and also showed antimicrobial and cytotoxic activity [6]. Since the black fruiting bodies of D. concentrica are highly melanized, it is likely that these compounds arise from melanin biosynthesis. Some naphthoquinones have been found to inhibit the motility and survival of H. contortus (LI). Plumbagin ( 173) was the most potent (ED 1 ig/ml) followed by 1, 4-naphthoquinone, juglone (174) and 1, 2-naphthoquinone [281]. 

CioHgOj, Mr 160.17, colorless platelets, mp. 140°C. A pentaketide from which typical metabolites of asco-mycetes are formed by oxidative coupling and other transformations. This family includes, e.g., bulgar-ein, 4,9-dihydroxy-3,10-perylenedione, and hypoxy-lone. Oxidative polymerization of 1,8-N. leads to brown to black fungal melanins, e.g., in the fruit bodies of the tree fungus Daldinia concentrica. Simple derivatives of 1,8-N., namely the monomethyl ether (C, H o02, Mr 174.20, cryst., mp. 55-56°C) and the dimethyl ether (C,2H,202, Mr 188.23, platelets, mp. 158-161 °C) were isolated from cultures of D. concentrica. 

A mixt. of fatty acid esters. Isol. from the fungus Daldinia concentrica. [a]g 126.5 (c, 0.3 in CHCI3). Related to Sclerotiorin, S-00352. 

Metab. of the fungus Daldinia concentrica. [a], 0 (CHCI3). Possible artifact. 

Bulgaria inquinans (210), Daldinia concentrica (14,15,16,19), Hypoxylon fuscum (339), H. sclerophaeum var. microspora (713)... 

Scheme 49. Inter-relationship of Daldinia concentrica metabolites...

There exists no direct evidence that naphthalene-1,8-diol (258) and consequently the quinones (260), (265), (266), and (269) are of polyke-tide origin. However, this hypothesis is supported indirectly by the presence in colourless mutants of Daldinia concentrica of several resorcinol derivatives formed by an alternative folding of a pentaketide chain 16). 

Biosynthetic Pathways in Daldinia concentrica. J. Chem. Soc. (London) 1960,... 

Daldinia concentrica (Bolt, ex Fr.) Cesati deNotaris 117,118,119,125 Dasyscyphus bicolor (Bull, ex Merat)... 

Metab. of Daldinia concentrica. Pale-yellow cryst. Tetra-Ac ... 

Produced by Daldinia concentrica. Used as 0.02Af MeOH soln. for extraction-fluorimetric detn. of Ti (A ax nm, 40% MeOH, CCI4). Yellow needles. Sol. MeOH. Mp 72-76°, Mp 90-91°. 

Isol. from a strain of Daldinia concentrica. Cryst. (pet. ether or EtOH). Mp 55-56° (47°). 

Produced by Daldinia concentrica. Leaflets (Et20 or EtOH aq.). Mp 158-161°. 

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