TOTAL SYNTHESIS OF THE TOXIN OOSPONOL AND OF STRUCTURAL ANALOGS AND INVESTIGATION OF THEIR ANTIBIOTIC ACTIVITIES

The toxic metabolite of the basidiomycete Gloeophyllum abietinum, oosp onol (6b), and the structural analogues (Figure 1) were synthesised in order to investigate which partial structures of the molecules are re sponsible for their biological activities. Different organisms were em ployed to test the antibiotic activities of the analogues. From the re sults obtained with the synthetic analogues of oosponol (6b), it becam e evident that the toxicity of this fungal metabolite can be attribute d to a vinylogous acid anhydride structure, which in nature is produce d by dehydrogenation of the nontoxic precursor oospoglycol (7).