Metabolites of the higher fungi. Part 31.1 Longianone, a C7H6O4 spiro bicyclic lactone from the fungus Xylaria longiana (Rehm.)

Dinemasones A, B and C – New Bioactive Metabolites from the Endophytic Fungus Dinemasporium strigosum

“…Thus, the presence of the cis-diol 3a, named dinemasone C, could only be deduced indirectly (but unambiguously) from its acetylated product 3b. The four known metabolites palmitic acid, [2,3] ergosterol, [4] and the two diastereomers of 4-hydroxymellein [5] were identified by comparison of their spectroscopic data with those published in the literature.…”

“…The crude mass of the column fraction of petroleum ether/75 % CH 2 Cl 2 after crystallization from CH 2 Cl 2 /acetone gave white fine needles of ergosterol [4] (8.0 mg). The column fraction of petroleum ether/55 % CH 2 Cl 2 was subjected to preparative TLC on silica gel (CH 2 Cl 2 /MeOH/AcOH, 100:0.6:0.2) to obtain 2.3 mg of the cis and trans isomers of 4-hydroxymellein [5][6][7][8][9] as a mixture of two diastereomers. Chromatography of a polar fraction (CH 2 Cl 2 /1-2 % MeOH) on preparative layer silica gel plates (CH 2 Cl 2 /acetone/ AcOH, 100:4:0.2) followed by crystallization from CH 2 Cl 2 /Et 2 O/ pentane afforded dinemasone A (1a) (14.6 mg) as white fine needles.…”

“…A polar component 3a was indirectly identified by acetylation of the polar fraction as the cis-diacetylated derivative 3b, produced from the new natural product 3a (Figure 1). Both the hexahydropyrano [4,3-b]pyran-5(7H)-one derivative 2a and the 1,7-dioxaspiro [5,5]undecan-4-one derivative 1a showed antibacterial, antifungal, and antialgal activity.…”

“…From these extracts, four known compounds were identified as palmitic acid, [2,3] ergosterol, [4] and the cis and trans isomers of 4-hydroxymellein. [5][6][7][8][9] In addition, two new metabolites with unusual structures, 1a and 2a, were isolated in pure form by a combination of repeated chromatography and crystallization. A polar component 3a was indirectly identified by acetylation of the polar fraction as the cis-diacetylated derivative 3b, produced from the new natural product 3a (Figure 1).…”

Occurrence, isolation and biological activity of phytotoxic metabolites produced in vitro by Sphaeropsis sapinea, pathogenic fungus of Pinus radiata

“…(Krohn et al, 1997), Microsphaeropsis spp. (Hoeller et al, 1999) and Xylaria longiana (Edwards et al, 1999) has been reported. The biological properties of mellein include: phytotoxic activity on tomato cuttings at 0.1 mg ml )1 and zootoxic activity to brine shrimp (Artemia salina) at 0.2 mg ml )1 (Parisi et al, 1993), moderate antifungal activity in agar diffusion assays against Eurotium repens at 50 lg per test disk (Hoeller et al, 1999) and weak bioactivity in agar diffusion tests against E. repens, F. oxysporum and Ustilago violacea at 18 mg ml )1 (Krohn et al, 1997).…”