Oxasetin from Lophiostoma sp. of the Baltic Sea: identification, in silico binding mode prediction and antibacterial evaluation against fish pathogenic bacteria.

Because of the evolving resistance of microorganisms against existing antibiotics, there is an increasing need for new ones, not only in human, but also in veterinary medicine. The dichloromethane extract of a fungal strain of the genus Lophiostoma, isolated from driftwood collected from the coast of the Baltic Sea, displayed antibacterial activity against some fish pathogenic bacteria. Ergosterol epoxide (1), cerebroside C (2) and oxasetin (3) were isolated from the extract and structurally elucidated on the basis of spectroscopic data and chemical evidence.

Precursor-directed syntheses and biological evaluation of new elansolid derivatives.

The antibiotic elansolid C1 (8) was isolated from Chitinophaga sancti strain FxGBF13 after fermentation in the presence of anthranilic acid. Remarkably, 8 was also obtained by addition of anthranilic acid to a crude fermentation extract containing the macrolide elansolid A2 (1*). This Michael-type conjugate addition allowed us to generate 21 new derivatives of elansolid C1 (9-29) by using various nucleophiles.

Balticolid: a new 12-membered macrolide with antiviral activity from an ascomycetous fungus of marine origin.

A new 12-membered macrolide, balticolid (1) was isolated from the EtOAc extract of the culture broth of fungal strain 222 belonging to the Ascomycota, which was found on driftwood collected from the coast of the Greifswalder Bodden, Baltic Sea, Germany. The structure of balticolid was determined to be (3R,11R), (4E,8E)-3-hydroxy-11-methyloxacyclododeca-4,8-diene-1,7-dione using extensive spectral data as well as the modified Mosher ester method. Balticolid (1) displayed anti-HSV-1 activity with an IC₅₀ value of 0.

Balticols A-F, new naphthalenone derivatives with antiviral activity, from an ascomycetous fungus.

Six new naphthalenone derivatives, balticols A-F and the known metabolite altechromone A were isolated from the AcOEt extract of the culture broth of fungal strain 222 belonging to the Ascomycota, which was found on driftwood collected at the coast of the Greifswalder Bodden, Baltic Sea, Germany. All structures were elucidated on the basis of NMR spectroscopic data and mass spectrometric analyses. The balticols were found to exhibit inhibitory activity against influenza virus A and herpes simplex virus.